Type 56 05-MultizoneBuilding

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TRNSYS 17 – Multizone Building modeling with Type56 and TRNBuild

TRNSYS 17 a T R a N s i e n t S Y s t e m S i m u l a t i o n p r o g r a m

Volume 5

Mul t izone Bui ld ing model ingwi th Type56 and TRNBui ld

Solar Energy Laboratory, Univ. of Wisconsin-Madisonhttp://sel.me.wisc.edu/trnsys

TRANSSOLAR Energietechnik GmbHhttp://www.transsolar.com

CSTB – Centre Scientifique et Technique du Bâtimenthttp://software.cstb.fr

TESS – Thermal Energy System Specialists, LLChttp://www.tess-inc.com


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Abo ut This Manual

The information presented in this manual is intended to provide a complete reference onmultizone building simulation with TRNSYS. It includes a description of the building model (knownas Type 56) and a user guide for the associated visual interface (TRNBuild). This manual is not

intended to provide detailed information about the TRNSYS simulation software nor any of itsother utility programs. Detailed information concerning these programs can be found in otherparts of the TRNSYS documentation set. The latest version of this manual is always available forregistered users on the TRNSYS website (see here below).

Revis ion his tory

2004-09 For TRNSYS 16.00.0000

2005-04 For TRNSYS 16.00.0038

2005-11 For TRNSYS 16.01.0000

2007-02 For TRNSYS 16.01.0003

2009-11 For TRNSYS 17.00.0006 2010-02 For TRNSYS 17.00.0009

2012-02 For TRNSYS 17.01.0006

Where to f ind m ore informat ion

Further information about the program and its availability can be obtained from the TRNSYSwebsite or from the TRNSYS coordinator at the Solar Energy Lab:

TRNSYS Coordinator

Solar Energy Laboratory, University of Wisconsin-Madison1500 Engineering Drive, 1303 Engineering Research BuildingMadison, WI 53706 – U.S.A.

Email: [email protected]

Phone: +1 (608) 263 1586Fax: +1 (608) 262 8464

TRNSYS website: http://sel.me.wisc.edu/trnsys

Not ice

This report was prepared as an account of work partially sponsored by the United StatesGovernment. Neither the United States or the United States Department of Energy, nor any oftheir employees, nor any of their contractors, subcontractors, or employees, including but notlimited to the University of Wisconsin Solar Energy Laboratory, makes any warranty, expressed

or implied, or assumes any liability or responsibility for the accuracy, completeness or usefulnessof any information, apparatus, product or process disclosed, or represents that its use would notinfringe privately owned rights.

© 2005 by the Solar Energy Laboratory, University of Wisconsin-Madison

The software described in this document is furnished under a license agreement. This manualand the software may be used or copied only under the terms of the license agreement. Exceptas permitted by any such license, no part of this manual may be copied or reproduced in any form


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or by any means without prior written consent from the Solar Energy Laboratory, University ofWisconsin-Madison.

Type 56 Con tr ibuto rs

The TRNBuild program described in this manual was developed by TRANSSOLAREnergietechnik GmbH, the German distributor of TRNSYS. Further information about theprograms and their availability can be obtained from the TRNSYS distributor from which youpurchased the programs or:

TRANSSOLAR Energietechnik GmbHCuriestr. 2

70563 StuttgartGermany

Phone: +49/ 711 / 679 76 - 0Fax: +49/ 711 / 67976 - 11

E-mail: [email protected]://www.trnsys.de

Sections which are new compared to TRNSYS Version 15 are marked in blue.

Sections which are new compared to TRNSYS Version 16 are marked in red.


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Table of contents

5. MULTIZONE BUILDING MODELING WITH T YPE56 AND TRNBUILD 5 –8

5.1. Introduction 5 –8

5.2. TRNBuild 5 –9

5.2.1. Introduction 5 –9

5.2.2. Getting Started 5 –11

5.2.2.1. Settings 5 –12

5.2.2.2. Opening and Creating a New File 5 –14

5.2.2.3. Importing a Trnsys3d file 5 –15

5.2.2.4. Specifying the Required Input 5 –16

5.2.3. The Project Initialization Window 5 –19

5.2.3.1. Orientation 5 –20 5.2.3.2. Properties 5 –22

5.2.3.3. Inputs 5 –23

5.2.3.4. Outputs 5 –24

5.2.3.5. Balance Outputs 5 –42

5.2.4. The Zone Window 5 –48

5.2.4.1. Input of the Required Regime Data 5 –49

5.2.4.2. Input of Walls 5 –50

5.2.4.3. Input of Windows 5 –70

5.2.4.4. Infiltration 5 –77

5.2.4.5. Ventilation 5 –78

5.2.4.6. Heating 5 –80

5.2.4.7. Cooling 5 –82

5.2.4.8. Gains 5 –83

5.2.4.9. Comfort 5 –85

5.2.4.10. Coupling between airnodes of same zone 5 –88

5.2.4.11. Geometry Modes 5 –88

5.2.4.12. Radiation Modes 5 –89

5.2.5. The Type Managers 5 –92

5.2.6. Geometry Information 5 –93

5.2.7. Generating Files 5 –94

5.2.7.1. Generating TYPE56 Standard Files 5 –94

5.2.7.2. Generating Shading / Insolation matrix 5 –95

5.2.7.3. Generating view factor matrix 5 –96


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5.2.7.4. Maximum heat load calculation 5 –96

5.2.8. Exporting Trnsys3d file 5 –98

5.2.9. Input Data Limits of TRNBuild 5 –99

5.2.10. Building Input Description File(BUI) - Created By TRNBuild 5 –99

5.2.10.1. Rules Governing the “BID Language” 5 –99

5.2.10.2. Properties 5 –101

5.2.10.3. Types 5 –103

5.2.10.4. Orientations 5 –118

5.2.10.5. Building 5 –119

5.2.10.6. Radiation Mode 5 –119

5.2.10.7. Geometry Mode 5 –120

5.2.10.8. Walls 5 –121

5.2.10.9. Windows 5 –131

5.2.10.10. Regime 5 –134

5.2.10.11. Output 5 –137

5.2.10.12. EXTENSION_WINPOOL 5 –139

5.2.10.13. EXTENSION_BuildingGeometry 5 –139

5.2.10.14. EXTENSION_VirtualSurfaceGeometry 5 –140

5.2.10.15. EXTENSION_ShadingGeometry 5 –141

5.2.10.16. EXTENSION_GEOPositionGeomtry 5 –141

5.3. TRNSYS Component Configuration 5 –143

5.3.1. Parameters 5 –143

5.3.2.

Inputs 5 –144

5.3.3. Outputs 5 –145

5.4. Mathematical Description of Type 56 5 –146

5.4.1. Thermal Zone /Airnode 5 –146

5.4.1.1. Convective Heat Flux to the Air Node 5 –146

5.4.1.2. Coupling 5 –147

5.4.1.3. Radiative Heat Flows (only) to the Walls and Windows 5 –148

5.4.1.4. Integration of Walls and Windows 5 –149

5.4.1.5. Transfer Function Method by Mitalas 5 –151

5.4.1.6. The Long-Wave Radiation 5 –153 5.4.1.7. Detailed Radiation Transfer Model 5 –157

5.4.1.8. Distribution of Long-Wave Radiation Internal gains 5 –158

5.4.1.9. Distribution of Solar Radiation 5 –159

5.4.1.10. External Walls 5 –162

5.4.1.11. Walls with Boundary Conditions 5 –163

5.4.1.12. Adjacent, Internal Walls and Walls with Identical Boundary Conditions 5 –163


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5.4.1.13. Total Gains from Surfaces in a Airnode 5 –164

5.4.1.14. Infiltration, Ventilation, and Convective Coupling 5 –165

5.4.1.15. Floating Airnode Temperature (No Heating or Cooling) 5 –166

5.4.1.16. Simplified Heating and Cooling 5 –168

5.4.1.17. Simulation Timestep versus Wall Timebase 5 –171 5.4.2. Optical and Thermal Window Model 5 –172

5.4.2.1. Description of the Window 5 –173

5.4.2.2. 2-Band-Solar-Radiation-Window-Model 5 –173

5.4.2.3. Transmission of Solar Radiation 5 –174

5.4.2.4. Heat Flux between Window Panes 5 –174

5.4.2.5. Absorption of Short-Wave Radiation 5 –176

5.4.2.6. Iterative Solution for Pane Temperatures 5 –176

5.4.2.7. Total Energy Flux through the Window Glazing 5 –177

5.4.2.8. Edge Correction and Window Frame 5 –177 5.4.2.9. External and Internal Shading Devices 5 –178

5.4.3. Moisture Balance 5 –180

5.4.3.1. Effective Capacitance Humidity Model 5 –180

5.4.3.2. Buffer Storage Humidity Model 5 –181

5.4.3.3. Mathematical Description of the Buffer Storage Humidity Model 5 –182

5.4.3.4. Buffer Storage Example 5 –185

5.4.3.5. Comparison of Measurement and Simulation for the Buffer Storage Humidity Model 5 –186

5.4.4. Integrated Model for Thermo-Active Building Elements 5 –187

5.4.4.1. Stationary solution in the x –y plane of a thermo-active construction element 5 –188 5.4.4.2. Thermal transmittance through the pipe shell 5 –192

5.4.4.3. Mean water temperature in a pipe coil 5 –193

5.4.4.4. Total resistance 5 –194

5.4.4.5. Comparing the calculation methods 5 –196

5.4.4.6. Variables and Indices 5 –199

5.4.5. Integrated Model for Chilled Ceiling Panels 5 –199

5.4.6. Comfort model 5 –206

5.4.7. References 5 –210

5.5. Mathematical Description of Auxiliary Tools 5 –211 5.5.1. TRNSHD 5 –211

5.5.2. View factor calculation 5 –214

5.6. Building Examples for TYPE 56 5 –215

5.6.1. Introduction 5 –215

5.6.2. From the architectural model to thermal model 5 –217

5.6.3. 3D Building Example: 3-Zone Building 5 –217


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5.6.3.1. 3D Building definition by Trnsys3d 5 –219

5.6.3.2. 112BCreating a building project by the 3D-Building Wizard 5 –220

5.6.3.3. 113BModification of the building description (TRNBuild) 5 –222

5.6.3.4. 114BModification of the building project (Studio) 5 –223

5.6.3.5. 115B

TRNSYS Input File, Simulation, Results 5 –224 5.6.3.6. 116BModifying the geometric part of the building model 5 –227

5.6.4. Simple Building Example: Restaurant 5 –228


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5. MULTIZONE BUILDING MODELINGWITH T YPE56 AND TRNBUILD

5.1. Introduction

This component models the thermal behavior of a building divided into different thermal zones. Inorder to use this component, a separate pre-processing program must first be executed. TheTRNBUILD program reads in and processes a file containing the building description andgenerates two files that will be used by the TYPE 56 component during a TRNSYS simulation.The file containing the building description processed by TRNBUILD can be generated by theuser with any text editor or with the interactive program TRNBUILD. The required notation isdescribed fully in the TRNBUILD documentation in the following section. 3 parameters arerequired by the TYPE 56 component. The first parameter is the FORTRAN logical unit for thedata file with the building data (*.BUI). Since Version 16 this file contains also the thermal andoptical data for all windows used in a project. The Data is taken from the Program Window libraryThis ASCII file is distributed with TYPE 56 and may be extended using the DOE2 Output ofWINDOW 4.1 or 5 program developed by Lawrence Berkeley Laboratory, USA. The secondparameter is set to 1 if time-dependent convective heat transfer coefficients are used (forexample in combination with floor panel heating systems). The third parameter gives theweighting factor between air and mean surface temperature for the calculation of an operativeroom temperature. The inputs and outputs of TYPE 56 depend upon the building description andoptions within the TRNBUILD program. TRNBUILD generates an information file describing theoutputs and required inputs of TYPE 56.

There are two ways to model the equipment for heating, cooling, humidification, and

dehumidification. The two methods are similar to the "energy rate" and "temperature level" controlmodes available in the TYPE 12 and 19 load models. With the "energy rate" method, a simplifiedmodel of the air conditioning equipment is implemented within the TYPE 56 component. The userspecifies the set temperatures for heating and cooling, set points for humidity control, andmaximum cooling and heating rates. These specifications can be different for each zone of thebuilding. If the user desires a more detailed model of the heating and cooling equipment, a"temperature level" approach is required. In this case, separate components are required tomodel the heating and/or cooling equipment. The outputs from the TYPE 56 zones can be usedas inputs to the equipment models, which in turn produce heating and cooling inputs to the TYPE56 zones.

Note: Only one unit of TYPE 56 is allowed per simulation.

There are 4 main sections in this guide:

Section Error! Reference source not found. explains how to use the TRNBuild program todefine the multizone building data for TYPE 56 of TRNSYS.

Section 5.3 shows the configuration of TYPE 56 (Parameters, Inputs, Outputs)

Section 5.4 describes the mathematical models and assumptions behind the Type56multizone building model.

Section 5.5 presents building examples


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5.2. TRNBuild

5.2.1. Introduct ion

Due to the complexity of a multizone building the parameters of TYPE 56 are not defined directlyin the TRNSYS input file. Instead, a file so-called building file (*.BUI) is assigned containing therequired information.

TRNBUILD (formerly known as PREBID) has been developed to provide an easy-to-use tool forcreating the BUI file. Starting with some basic project data, the user describes each thermal zonein turn. Finally, the desired outputs are selected. All data entered are saved in the so-calledbuilding file (*.BUI), a readable ASCII text file. The BUI file is very handy for checking dataentered in TRNBuild.

Note: The BUI-file has a rigorous syntax. Editing this file may cause a lot of trouble!

Compared to the previous version, several improvements have been made to TRNBuild and tothe multizone building model itself (TYPE 56):

User interface TRNBuild

Tree-structure of TRNBuild Navigator (Trnsys17.1)

Inputs / outputs window show complete lists as the INf file (Trnsys17.1)

Definition of hemisphere for generating orientations in standard format (Trnsys17.1)

Integrated radiation depending control for shading device of external windows (Trnsys17.1)

Internal radiation calculation for orientations in standard formatin conjunction with Type 15, 99, 16 (Trnsys17.1)

Radiation mode: solar to air factor (Trnsys17.1) Export 3D building data into IDF (without *_b17.idf) (Trnsys17.1)

Import /Update of geometric information via an IDF file (Trnsys17)

Generation of shading / insolation matrices (Trnsys17)

Generation of view factor matrices (Trnsys17)

Multi-airnode zones (Trnsys17)

New NTYPES (Trnsys17)

Physical and mathematical modeling:

Integrated radiation depending control for shading device of external windows (Trnsys17.1) Internal radiation calculation for orientations in standard format

in conjunction with Type 15, 99, 16 (Trnsys17.1)

Radiation mode: solar to air factor (Trnsys17.1)

Detailed shading of beam and diffuse solar radiation of external windows (Trnsys17)

Detailed geometric distribution of primary beam radiation within a zone (Trnsys17)

Detailed geometric distribution of diffuse radiation within a zone (Trnsys17)


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Detailed geometric longwave radiation exchange within a zone (Trnsys17)

Detailed comfort model

TRNSYS16: User interface:

Automatic creation of T56 input files (*.bld,, *.trn, *.inf)

Chilled ceilings

Automatic segmentation of active layers

Improved library management (walls, layers, gains, schedules and windows),

Long variable names (all character s allowed except “blank” “:” “;”).

Rename/copy/paste/delete/new option in all TYPE-Managers (e.g. wall, window, gains)

Transparent insulation is treated like a normal window with a special data curve

TRNSYS16: Physical and mathematical modeling:

Automatic calculation of convective heat transfer coefficients depending on surface

temperatures

New 2-band radiation window model

Solar and thermal energy as well as moisture is automatically balanced

Note: Despite these improvements, the BUI-file created by TRNBuild 1.x can be imported intoTRNBuild 2.x. However, files can only be saved into a TRNBuild version 2.x format. Errors andunexpected behavior may occur by loading files which have been created or changed outside ofTRNBuild!


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5.2.2. Gettin g Started

Assuming that you have installed the TRNSYS package correctly, TRNBuild can be starteddirectly by double-clicking on the TRNBuild icon in the TRNSYS group. TRNBuild is also housed

within the TrnsysStudio environment program. (Note, that TRNBuild 1.0 requires a screenresolution of at least 800x600 and WINDOW NT or 95,98,2000 or newer).

The initial TRNBuild window is shown in Figure 5.2.2-1. The information window will closeautomatically. The main menu of the initial TRNBuild window houses the following items:

FILE (open, new, close, or save a *.BUI fil; import, export or update Trnsys3d file)

VIEW (toolbar, status bar)

OPTIONS (settings such as library versions, external editor, etc.)

WINDOW (cascade, tile, arrange icons, etc.)

HELP

After you opened a new or existing project three additional items will be available in the mainmenu:

ZONES (add and delete zones)

AIRNODES

GENERATE ( create BUI file for max. heat load calculation, run TRNSYS input file, generateshding/insolation matrix, generate view factor matrix)

TYPEMANAGER (new, edit, rename and copy TYPES of walls, windows, gains, ventilation,infiltration, cooling, heating, layers, and schedules)

Many of the features of the main menu are also present in the tool bar. For users with smallscreens, it might be more convenient to hide the toolbar and status bar.


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Figure 5.2.2-1: Initial TRNBuild Window

5.2.2.1. Settings

Under the OPTIONS menu, some settings used in TRNBuild can be specified as shown in Figure5.2.2-2. The Path for standard Libraries accessible in the settings window is only used for:

TRNSYS: spacer.lib

TRNFLOW: headers.txt, pollutant.lib

The path and name for all other libraries, for instance windows, walls, layers or schedules, will bepreset by the path given here, but can be changed interactively whenever needed, for examplewhen you are describing a new wall or window. Libraries for common windows, walls, and layersare provided in different languages:

The United States version contains Standard ASHRAE walls and materials.

The German version contains materials and walls according to DIN 4108 and VDI 2078,respectively. Glazing materials used on the German market have been added to the Germanwindow library.


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Figure 5.2.2-2: The SETTINGS Window

TRNBuild can import and update/export IDF files created by Trnsys3d for TRNSYS. A programcalled trnsidf.exe is used for importing the IDF, and for exporting/updating the IDF a programcalled trnsidfup.exe is used.

In addition, TRNBuild has the ability to generate a view factor matrix file. The application is calledtrnvfm.exe.

The location of the TRNSYS application is needed for running a “max. heat load calculation” (seeSection 5.2.7.4).The TRNSYS application name changed from formerly TRNSYS.exe toTRNExe.exe in version 16.

TRNBuild is able to create shading/insolation matrices for which the celestial hemisphere isdivided into patches based on the tregenza model. The resolution of the sky division can be set tomedium or high. For most projects a medium resolution issuifficient.

The new CHECK BOX "Files and Folders must exist" toggles on or off a test for the existence offile paths given in the input windows.


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5.2.2.2. Open ing and Creating a New File

To open an existing *.BUI file, click on FILE and then click on OPEN. To create a new file, clickon FILE and then click on NEW. The user is asked to select the hemisphere (northern/southern)corresponding to the location of the project. The hemisphere needs to be defined in order tocompute the correct azimuth angles of surface orientations.

Figure 5.2.2-3: Hemisphere Selection

Afterwards, the PROJECT INITIALIZATION window opens, as shown in Figure 5.2.2-4. If ZONEshave already been defined in this file, the ZONE windows are opened as well.

Figure 5.2.2-4: The PROJECT INITIALIZATION and ZONE Windows


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5.2.2.3. Import in g a Trnsys3d fi le

Instead of entering the surfaces manually in TRNBuild, three dimensional data created byTrnsys3d for TRNSYS can be imported. Trnsys3d for TRNSYS is a plugin for google SketchUp

TM

that allows you to create a building geometry from scratch: add zones, draw heat transfer

surfaces, draw windows, draw shading surfaces, etc. This information is saved in a *.IDF file.

Figure 5.2.2-5: The IMPORTING TRNSYS3D Window

To import an IDF file, select File “\Import Trnsys3d file” and select the Trnsys3d file. Thehemisphere (northern/southern) corresponding to the location of the project needs to be definedin order to compute the correct azimuth angles of surface orientations.

During the import, the following steps are performed:

sorting of zones/airnodes and surfaces

numbering of surfaces

volume calculation

surfaces with the construction type “VirtualSurfaces” aren‟t imported as heat transfersurfaces into TRNBuild. (They are used by volume calculation and export function only.)

generating of a *.B17 file and opening of the file in TRNBuild

generating of corresponding *_b17_IDF file with the same order of zones and surfacesand the same surface numbers. (Note: In TRNSYS 17, this file was used to go back fromTRNBuild to the Trnsys3d GUI. In Version 17.1, IDF files can be exported directly fromthe BUI file.

Note: For volume calculation the airnode has to be a closed volume!!

In TRNBuild non-geometric objects, such as materials, constructions, schedules, internal heatgains, heating, cooling, controls etc. are added to the project.


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5.2.2.4. Specify ing the Requir ed Inpu t

In TRNBuild windows, required information is entered in one of several formats: input box, radiobutton, list box, pull-down menu, or DEF button. The use of each of these formats is explainedbelow:

Input boxes

Input boxes are designed for the user to enter values or text, such as the name of a zone. Theyare easy to recognize by their light blue background color. (Note: gray colored boxes are used fordisplay only). Some input boxes require a number and will not accept other characters. To enterinformation in an input box, double-click anywhere in the input box and enter the requiredinformation using the keyboard.

Radio buttons

Radio buttons group a set of mutually exclusive options. The selected option is shown with ablack dot enclosed within a circle. To select a different radio button option with the mouse, justclick on the cycle in front of the option name.

List boxes

A list box provides a list of “source” items from which one or more can be selected as shown inFigure 5.2.2-6. Select an item with the mouse, scroll it into view if necessary using the scroll bar.Click on the upper arrow (pointing left) to add an item. The selected item appears in another boxon the left (see Figure 5.2.2-6). To delete an item, select the item in the left list and lick on thelower arrow (pointing right).Alternatively, the insert and delete key can used.

Figure 5.2.2-6: List Box Input

Pull-down menu

A pull-down menu provides a list of items from which only one can be selected. To select an item,click with the mouse on the arrow on the right side and keep the mouse button pressed whilelooking for the desired item. Release the mouse button when the desired item is highlighted. Thepull-down menu reduces again to a single bar and the selected item appears in a display box.

DEF button


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A DEF button is used to define items which can be a constant, an input or a schedule (i.e. theshading factor of an internal shading device as shown in Figure 5.2.2-7). In the display box, thedefined constant, input or schedule is displayed, respectively. „I‟ is the abbreviation for input and„S‟ the abbreviation for schedule.

Figure 5.2.2-7: The DEF Button

Figure 5.2.2-8: The DEFINITION Window for a Constant, an Input, or a Schedule

After clicking on the DEF button, a definition window opens as shown in Figure 5.2.2-8. A briefonline help is provided in an information box. Using a radio button, the user selects whether aconstant, an input or a schedule is to be defined:

For a constant, the user enters a single value.

For an input, the user selects an input from the pull-down menu as well as a multiplicationand addition factor. If the option NEW from the pull-down menu is selected, the user is askedto enter a new unique input name.

For defining a schedule, the user selects a schedule from the pull-down menu as well asmultiplication and addition factors. If the option NEW from the pull-down menu is selected, awindow for specifying the schedule appears as shown in Figure 5.2.2-9. This window offers

the option to define a daily or a weekly schedule. For a daily schedule, the user specifies thetype name first. Then the daily schedule is defined by entering values for the desired timeintervals. For a weekly schedule, the user selects a daily schedule for every day of the weekby a pull-down menu as shown in Figure 5.2.2-10. If the desired daily schedule has not yetbeen defined, the option NEW allows the user to define a new daily schedule.


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Figure 5.2.2-9: The SCHEDULE Window for a Daily Schedule

Figure 5.2.2-10: The SCHEDULE Window for a Weekly Schedule


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Figure 5.2.2-11: Getting a SCHEDULE for a Library

To take advantage of earlier defined schedules in libraries or any existing bui-file, scheduleinformation can be accessed through the path and file name dialog box at the window top.

5.2.3. The Project Init ial izat ion Wind ow

In the project initialization window, the user enters some general information about the project,defines the ORIENTATIONs of walls required by the described building, defines some basicmaterial properties, views the list of required INPUTS to TYPE 56, and selects the desiredOUTPUTS of TYPE 56.


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Figure 5.2.3-1: The PROJECT INITIALIZATION window

5.2.3.1. Orientation

All possible orientations of external building walls/windows must be defined here by uniquenames. The table contains all orientations defined for this project. For adding click on the “+”button and a new window for defining the opreintation opens. For deleting an orientation click onthe “-“ button. (Note: only “not used” orientations can be deleted).

In TRNSYS 17 a new standard format for orientation naming is introduced. This naming schemeincludes the azimuth and slope of surface acc. to TRNSYS convention:

Y_xxx_zzz

withY… single letter N, S, E, W or Hxxx… azimuth angle of the orientation acc. To TRNSYs convention (0…359 degree;

northern hemisphere: 0 … south; 90 … west, 180 … north, 270 … east southern hemisphere: 180 south; 90 … west, 0 … north, 270 … east )

zzz… slope of the orientation (0…180; 0 … horizontal, 90 … vertical, 180 … facing down)


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Figure 5.2.3-2: The NEW ORIENTATION window

The option “Internal calculation of radiation data” is a new feature of TRNSYS17.1 which reducesthe required input data from the weather data component significantly. For using this feature onlythe solar zenith (Input 5) has to be connected to the weather data component Type 15, Type16,Type99. For rotating the building using this option it is recommended to define an equation TURNin the TRNSYS Input f ile (e.g. “ TURN = 45 “ for rotation of 45 degrees towards west) andconnect the rotated solar azimuth angle (AAZM_TYPE56 = SolarAzimuthAngle – TURN”) toINPUT 6 of Type 56. If you use the studio wizards for creating a new building project theequations and connections are generated automatically.

If the option “external calculation of radiation data” is selected, three inputs of incident radiation to the Type 56 TRNSYS component will be required. This is generally provided by the weather

component.

A new feature of TRNSYS 17 is the geometric diffuse radiation shading. The orientation namedH_0_0 is automatically recognized as the horizontal radiation. If this orientation doesn‟t exist, nodiffuse geometric shading is performed.

It is highly recommended to use the standard format. The former so-called “free format” isavailable for backwards compatibility.


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5.2.3.2. Properties

Figure 5.2.3-3 shows certain material properties. If the user does not define them, the followingdefault values are used.

Figure 5.2.3-3: The PROPERTIES window

Heat transfer coefficients depend heavily on the temperature difference between surface and fluidand the direction of heat flow. For example, the flow pattern evolved by a chilled ceiling is similar


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to that of a heated floor, but completely different to that of a vertical surface. The mathematicalformula used for appropriate heat transfer coefficients is of the form

conv = const (Tsurf –Tair)exp

.

The coefficients const and exp can be changed here to fit different approaches from heat transferresearch. Standard values are taken from literature; see TRNSYS Manual, description of TYPE80 for further details.

Important note: the automatic calculation of heat transfer coefficients has to be activated duringthe description of a new wall (see Section 5.2.4.2) or in the WALL TYPE MANAGER and isapplied only to these explicitly defined walls. In case of heated or chilled building surface, theheat transfer will depend on surface temperature, so automatic heat transfer coefficientcalculation is strongly recommended.

For all other walls the standard approach will still be a constant heat transfer coefficient resultingin reduced calculation time.

5.2.3.3. Inputs

By clicking on the INPUTS button, an overview of INPUTs defined within the project is shown(see Figure 5.2.3-4).

New INPUTs can be added here, thus creating a list you want to use in the definition of gains,controller strategies etc. Unused INPUTs can be deleted, but it is not possible to delete INPUTSused in definitions somewhere in the building description. In certain cases it might be comfortableto change the sequence of INPUTs, which is done by drag and drop (left mouse button).

Figure 5.2.3-4: The INPUTS window


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5.2.3.4. Outputs

By clicking on the OUTPUTS button, the OUTPUTS window opens as shown in Figure 5.2.3-5. InGeneral, the definition of OUTPUTS is last step of the building description. The user may adjustthe time base of the transfer function if necessary. The default value of 1 is adequate for mostcases. For heavy constructions 2 up to 4 can be used, 0.5 for light walls. Caution: the start time in

the TRNSYS input file (*.DCK) must match to the time base.

Figure 5.2.3-5: The OUTPUT window

In addition, the user can edit, add or delete outputs of TYPE 56, so-called NTYPES. Defaultoutputs are provided (airnode air temperatures (NTYPE 1) and sensible energy demands(NTYPE2) for all specified zones). To add a new output, the user clicks on the ADD button andthe NEW OUTPUT window opens (see Figure 5.2.3-6). The user now has the following options:

to use a DEFAULT setting (airnode air temperatures (NTYPE 1) and sensible energydemands (NTYPE 2) for all specified airnodes)

to select a single or a group of airnodes use the arrows between the upper boxes or theinsert and delete key, respectively. Selected items appear in the left boxes. For specifyingthe desired outputs use the lower list boxes. Selected outputs appear in the lower left box,simultaneously selected items appear in a different color in the lower right box to preventfrom multiple selection.

in addition to outputs for specified airnodes, balances are available for thermal energy, solar

radiation and humidity, extremely helpful for consistency check of thermal modeling.

If a so-called surface output is selected, the desired surfaces must be defined by a doubleclick on the NTYPE of the left box. Afterwards, the selected surface numbers are displayedtoo. Also, for NTYPE 28 (values of schedules) the schedules must specified by a doubleclick on the NTYPE of the left box.

If a so-called comfort output is selected, the desired comfort type must defined by doubleclicking on the NTYPE of the left box. Afterwards, the selected comfort numbers aredisplayed.


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For editing a previously defined OUTPUT, double-click on the output in the lower left Ntypesoverview window.

Figure 5.2.3-6: Adding a new user-defined OUTPUT

In Table 5.2.3-1 below, a list of optional outputs is shown. Table 5.2.3-1 is divided into so called“airnode outputs” where a single output is produced for each airnode specified and so called“surface outputs” where a single output is produced for specified surfaces of a n airnode. Inaddition, outputs for groups of airnodes can be defined. Airnodes are combined in groups bystating the airnodes in a row and then specifying the desired NTYPE numbers of possible groupoutputs. For each of these NTYPE numbers, a group output for the stated zones is produced.

Beginning in TRNSYS 17, a thermal zone is not equal to an airnode. A thermal zone may consistof more than one airnode. All zone outputs are now airnode outputs except for the balanceoutputs.


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Table 5.2.3-1: Optional Outputs

Airnodes Outputs:

NTYPE# Label Description Unit

NTYPE 1 TAIR air temperature of Airnode [°C]

NTYPE 2 QSENS sensible energy demand, heating(-), cooling(+) [kJ/hr]

NTYPE 3 QCSURFtotal convection to air from all surfaces within airnode incl.internal shading

[kJ/hr]

NTYPE 4 QINF sensible infiltration energy gain of airnode [kJ/hr]

NTYPE 5 QVENT sensible ventilation energy gain of airnode [kJ/hr]

NTYPE 6 QCOUP sensible coupling gains of airnode [kJ/hr]

NTYPE 7 QGCONV internal convective gains of airnode [kJ/hr]

NTYPE 8 DQAIRsensible change in internal energy of air in airnode sincethe beginning of the simulation

[kJ/hr]

NTYPE 9 RELHUM relative humidity of airnode air [%]

NTYPE 10 QLATDlatent energy demand of airnode, humidification(-),dehumidification (+)

[kJ/hr]

NTYPE 11 QLATGlatent energy gains of airnode including ventilation,infiltration, coupling, internal latent gains and vaporadsorption in walls

[kJ/hr]

NTYPE 12 QSOLTRtotal shortwave solar radiation transmitted through externalwindows of airnode (but not kept 100 % in airnode)

[kJ/hr]

NTYPE 13 QGRAD Defined internal radiative gains of airnode [kJ/hr]

NTYPE 14 QTABSItotal radiation absorbed (or transmitted) at all inside surf.of airnode (includes solar gains, radiative heat, internalradiative gains and wallgains)

[kJ/hr]

NTYPE 15 QTABSO

total radiation absorbed at all outside surf. of airnode(includes solar gains, radiative heat, internal radiativegains and wallgains, but not longwave radiation exchange

with Tsky)

[kJ/hr]

NTYPE 16 QTCOMOtotal convective and longwave rad. gains (T sky) to outsidesurf.

[kJ/hr]


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Surface Outputs:


NTYPE 17 TSI inside surface temperature [°C] [°C]

NTYPE 18 TSO outside surface temperature [°C] [°C]

NTYPE 19 QCOMIenergy from inside surf. incl. conv. to air and longwaveradiation to other surfaces

[kJ/hr]

NTYPE 20 QCOMOenergy to outside surf. incl. conv. to air and longwaveradiation to other surfaces or Tsky

[kJ/hr]

NTYPE 21 QABSI

absorbed (or transmitted) at inside surf (includes solargains, radiative heat, internal radiative gains andwallgains, except longwave radiation exchange with otherwalls)

[kJ/hr]

NTYPE 22 QABSOradiation absorbed at outside surf. [kJ/hr] (includes solargains, radiative heat, internal radiative gains andwallgains, except longwave radiation exchange with otherwalls or Tsky)

[kJ/hr]

Airnode Outputs:


NTYPE 23 TSTAR star node temperature of airnode [°C]

NTYPE 24 TMSURF weighted mean surface temperature of airnode [°C]

NTYPE 25 TOP operative airnode temperature [°C]

NTYPE 26 QVAPW heat of vapor adsorption in walls of airnode [kJ/hr]

NTYPE 27 QUA static UA-transmission losses (UA*dT) of airnode [kJ/hr]

NTYPE 28 value of schedule

NTYPE 29 ABSHUM absolute humidity of airnode air [kgwater / kgdry_air ]

NTYPE 30

QHEAT

sensible heating demand of airnode (positive

values) [kJ/hr]

NTYPE 31QCOOL

sensible cooling demand of airnode (positivevalues)

[kJ/hr]

Note: NTYPE 27 (static UA-transmission losses of walls + windows of airnode) and NTYPE 46do not use the transfer functions calculated by BID but instead uses the stationary U-values tocalculate steady state transmission losses of walls and windows without considering any


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capacitance effects. The following values of the surface resistance (combined for convection andradiation) are used for the U-value calculation:

HBACK > 30 kJ / (h m² K) => 1/α = 0.04 m² K / W

30 ≥ HBACK >0.005 => 1/α = 0.13 m² K / W

0.005 ≥ HBACK => 1/α = 0 m² K / W

HFRONT => 1/α = 0.13 m² K / W

If the NTYPE 27 and 46 are used in short term calculations, large errors in the energy balances ofthe building may occur due to the neglect of internal energy changes within massive walls.


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Outputs for Groups of Airnodes:


NTYPE 32 SQHEATsum of sensible heating demand for specifiedairnodes (positive)

[kJ/hr]

NTYPE 33 SQCOOLsum of sensible cooling demand for specifiedairnodes (positive)

[kJ/hr]

NTYPE 34 SQCSURF sum of surf. conv. gains of specified airnodes [kJ/hr]

NTYPE 35 SQINFsum of sensible infiltration gains of specifiedairnodes

[kJ/hr]

NTYPE 36 SQVENTsum of sensible ventilation gains of specifiedairnodes

[kJ/hr]

NTYPE 37 SQCOUPsum of sensible coupling gains of specified

airnodes

[kJ/hr]

NTYPE 38 SQGCONV sum of int. conv. gains of specified airnodes [kJ/hr]

NTYPE 39 SDQAIRsum of changes in internal energy of air inspecified airnodes (since the beginning of thesimulation)

[kJ/hr]

NTYPE 40 SQLATDsum of latent energy demand of specified airnodeshumidification(-), dehumidification (+)

[kJ/hr]

NTYPE 41 SQLATGsum of latent energy gains of specified airnodesincluding ventilation, infiltration, coupling and

vapor adsorption in walls

[kJ/hr]

NTYPE 42 SQSOLTsum of shortwave solar radiation transmittedthrough windows of specified airnodes (but notkept 100 % in airnode)

[kJ/hr]

NTYPE 43 SQGRADsum of internal radiative gains of specifiedairnodes

[kJ/hr]

NTYPE 44 SQABSItotal rad. absorbed (or transmitted) at inside surf.of specified airnodes (includes solar gains, rad.heat, int. rad. and wallgains)

[kJ/hr]

NTYPE 45 SQABSOtotal rad. absorbed at outside surf. of specifiedairnodes (incl. solar gains, rad. heat, int. rad. andwallgains, but not l-wave with Tsky)

[kJ/hr]

NTYPE 46 SQUAsum of static transmission losses (UA*dT) ofspecified airnodes

[kJ/hr]

NTYPE 47 SQVAPWsum of heat of vapor adsorption in walls ofspecified airnodes

[kJ/hr]


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Surface Outputs:


NTYPE 48 ICOND condensation flag (0 or 1) for inside surfaces

NTYPE 49 OCOND condensation flag (0 or 1) for outside surfaces

NTYPE 50 UWIN U-value of glazing and frame for external windows [kJ/ hr m² K]

NTYPE 51 GWIN g-value (solar heat gain coeff.) of glazing only

NTYPE 52 TIGLS inside surface temperature of the glazing [°C]

NTYPE 53 TOGLS outside surface temperature of the glazing [°C]

NTYPE 54 TIFRM inside surface temperature of the frame [°C]

NTYPE 55 TOFRM outside surface temperature of the frame [°C]

Airnode Outputs:


NTYPE 56 QSEC secondary heat flux of all windows of airnode [kJ/hr]

Surface Outputs:


NTYPE 57 TALM node temperature of active layer [°C]

NTYPE 58 TOFL fluid outlet temperature of active layer [°C]

NTYPE 59 QALFL

energy input by fluid of active layer to active layer

(> 0: cooling, < 0: heating)[kJ/hr]

NTYPE 60 QALE energy input by gains of active layer to active layer [kJ/hr]

NTYPE 61 QALTLtotal energy input by fluid&gains of active layer toactive layer

[kJ/hr]


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Airnode Outputs:


NTYPE 62 PMV predicted mean vote (PMV) value of airnode

NTYPE 63 PPD predicted percentage of dissatisfied persons(PPD) value of airnode [%]

Surface Outputs:


NTYPE 64 QSGL solar rad. absorbed on all panes of window [kJ/hr]

NTYPE 65 QSISHsolar rad. absorbed on internal shading device ofwindow

[kJ/hr]

NTYPE 66 QSOFRsolar rad. absorbed on outside of ext. windowframe

[kJ/hr]

NTYPE 67 QSIFRsolar rad. absorbed on inside frame and both sidesof adjacent windows

[kJ/hr]

NTYPE 68 QSOUTsolar transmission to outside through externalwindow

[kJ/hr]


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Zone Outputs:


NTYPE 69 QTSGLtotal solar rad. absorbed on all panes of allwindows of a zone

[kJ/hr]

NTYPE 70 QTSISHtotal solar absorbed on internal shading device ofall windows of a zone

[kJ/hr]

NTYPE 71 QTSOFRtotal solar rad. absorbed on outside of the frame ofext. window

[kJ/hr]

NTYPE 72 QTSIFRtotal solar rad. absorbed on inside of the frame ofall ext. window and both sides of all adjacentwindows of a zone

[kJ/hr]

NTYPE 73 QTSOUTtotal solar transmission to outside through externalwindow of a zone

[kJ/hr]

NTYPE 74 QTSPAS

total solar radiation passing the glass surface ofexternal windows (absorption on external shadingdevices and reflection of external glass surface areexcluded! -> total radiation absorbed ortransmitted by building components)

[kJ/hr]

NTYPE 75 QTSABStotal solar rad. absorbed at all inside surfaces of azone

[kJ/hr]

NTYPE 76 QTWG total wallgains on inside surfaces of a zone [kJ/hr]

NTYPE 77 QTSKYtotal longwave rad. losses to sky of outside

surfaces of a zone

[kJ/hr]

NTYPE 78 QRHEATradiative energy rate of sensible heating demandof a zone

[kJ/hr]


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Surface Outputs:


NTYPE 79 QSIABsolar (direct & diffuse) rad. absorbed at insidesurface

[kJ/hr]

NTYPE 80 QIBAB solar direct rad. absorbed at inside surface [kJ/hr]

NTYPE 81 QIDAB solar diffuse rad. being absorbed at inside surface [kJ/hr]

NTYPE 82 QWG wall gain on inside surface of wall or window [kJ/hr]

NTYPE 83 QSKY longwave rad. losses to sky of external surface [kJ/hr]

NTYPE 84 QRGAB internal rad gains absorbed on inside surface [kJ/hr]

NTYPE 85 QRHEArad. energy rate of sens. heating demandabsorbed on inside surf

[kJ/hr]

NTYPE 86 REQVequivalent resistance between star node andsurface

[(hr K)/kJ]

Airnode Outputs:


NTYPE 90 THEAT Set temperature heating [°C]

NTYPE 91 PHMAX Maximum power of heating [kJ/hr]

NTYPE 92 HUMHEAT Desired Humidity for heating [%] or [kg/kg]

NTYPE 93 TCOOL Set temperature cooling [°C]

NTYPE 94 PCMAX Maximum power of cooling [kJ/hr]

NTYPE 95 HUMCOOL Desired Humidity for cooling [%] or [kg/kg]

NTYPE 96 ACHINF Airchange rate infiltration [1/h]

NTYPE 97 GABSHUM humidity gain of defined gains [kg/kg]

NTYPE 98 QDEHUMlatent energy demand of airnode bydehumidification (positive values)

[kJ/hr]

NTYPE 99 QHUMlatent energy demand of airnode by humidification(positive values)

[kJ/hr]


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Surface Outputs:


NTYPE 100 ISHADE Internal shading factor of window [-]

NTYPE 101OSHADB

Total external shading factor of window fordirect radiation incl. geometric shading

[-]

NTYPE 102OSHADD

Total external shading factor of window fordiffuse radiation incl. geometric shading

[-]

NTYPE 103IBSHAD

Total direct radiation on outside of externalsurface (incl. shading)

[kJ/hr]

NTYPE 104IDSHAD

Total diffuse radiation on outside of externalsurface (incl. shading)

[kJ/hr]

NTYPE 105 FSOLB1Primary beam radiation distribution factor ofinside surface [-]

NTYPE 106FSOLB2

Non-primary beam radiation distribution factorof inside surface

[-]

NTYPE 107 HCONVO eff. outside conv. heat transfer coeff (BACK) [kJ/hr m² K]

NTYPE 108 HCONVI eff. inside conv. heat transfer coeff (FRONT) [kJ/hr m² K]

NTYPE 109 QSICONV Energy gain inside by convection [kJ/hr]

NTYPE 110QABSILW

Energy absorbed on inside surface bylongwave radiation exchange

[kJ/hr]

NTYPE 111 TIFL Inlet temperature of active layer [°C]

NTYPE 112 MFLAL Inlet mass flow rate of active layer [kg/hr]

NTYPE 113 AREA surface area [m²]

NTYPE 114IB

Incident direct radiation on outside of externalsurfaces (without shading effects)

[kg/hr]

NTYPE 115ID

Incident diffuse radiation on outside of externalsurfaces (without shading effects)

[kg/hr]

NTYPE 116IT

Incident total radiation on outside of externalsurfaces (without shading effects)

[kg/hr]


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Airnode Outputs:


NTYPE 117 VOLUME Air volume of airnode [m³]

NTYPE 118 QSOLAIR

convective energy gain of airnode duetransmitted solar radiation through externalwindows which is transformed immediately intoa convective heat flow

[kg/hr]

Surface Outputs:


NTYPE 119 SHADCNTRL

Shading control signal for integrated radiationdepending shading of external windows

(0..integrated shading control not active, 1..integrated shading control active (=closed))

[-]

Comfort Outputs:


NTYPE 120 TMRLW Mean radiant temperature (longwave only) [°C]

NTYPE 122 TOPLW Operative temperature (longwave only) [°C]

NTYPE 124 PMVLW Predicted mean vote (longwave only) [-]

NTYPE 126PPDLW

Percentage of person dissatisfied (longwaveonly)

[%]


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Balance Outputs:


NTYPE901

Bal_1 Solar Balance for Zones [kJ/hr]

NTYPE902

Bal_2 Solar Balance for Sum of all Zones [kJ/hr]

NTYPE903

BAL_3 Solar Balance for External Window [kJ/hr]

NTYPE904

BAL_4 Energy Balance for Zones [kJ/hr]

NTYPE905

BAL_5 Energy Balance for Sum of all Zones [kJ/hr]

NTYPE906

BAL_6 Energy Balance for Surfaces [kJ/hr]

NTYPE907

BAL_7 Moisture Balance for Airnodes [kJ/hr]

NTYPE908

BAL_8 Moisture Balance for Sum of all Airnodes [kJ/hr]

Since Version 16 automatic balances are available. The balance output can be chosen like anormal output in TYPE56. In order to avoid to large files the balance is then printed hourly. The

balance output files are printed in the directory of the TRNSYS input file DCK. Since version 17the values are integrated. In addition, each individual variable of each balance is available as anNTYPE. Also, the nomenclature of the variables has been improved. The balance outputs aredescribed in detail in section: 5.2.3.5


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Zone Outputs corresponding to Balance 901 (see 5.2.3.5.1):


NTYPE910

B1_QBAL BAL 1: solar balance for one zone[kJ/hr]

NTYPE911

B1_QSEXTBAL 1: total external solar radiation on allwindows of one zone including frame

[kJ/hr]

NTYPE912

B1_QSADJBAL 1: solar gains due to exchange withadjacent zones (gains +; Losses -). Includingmultiple refection.

[kJ/hr]

NTYPE913

B1_QBREFGBAL 1: solar blocked due to reflection ofglazing of all windows of a zone

[kJ/hr]

NTYPE

914

B1_QBABSGBAL 1: solar blocked due to absorption onglazing of all external windows (only absorbed

gains not entering the zone)

[kJ/hr]

NTYPE915

B1_QBFRM

BAL 1: solar blocked due to frames of allwindows of a zone. Secondary heat flux intozone from absorbed solar on external surfaceof frame is not included

[kJ/hr]

NTYPE916

B1_QBESHDBAL 1: solar blocked due to external shadingdevices of all windows of a zone

[kJ/hr]

NTYPE917

B1_QSLOSSBAL 1: solar radiation leaving zone throughexternal windows of zone (excluding solarreflected by internal shading device)

[kJ/hr]

NTYPE918

B1_QSGWIN

BAL 1: Absorbed solar gains on all windows ofzones going inside (secondary heatflux for totalwindow including frame and internal shadingdevice without CCISHADE Part)

[kJ/hr]

NTYPE919

B1_QBRISHDBAL 1: solar blocked due to reflection oninternal shading devices of all windows of azone

[kJ/hr]

NTYPE920

B1_QISHCCIBAL 1: Absorbed on all internal shadingdevices of zone and directly transferred to theairnode by ventilation (CCISHADE)

[kJ/hr]

NTYPE921

B1_QSGWALLBAL 1: absorbed solar radiation on all walls ofzone

[kJ/hr]

B1_QSOLAIR

BAL 1: convective energy gain of zone duetransmitted solar radiation through externalwindows which is transformed immediately intoa con. heat flow to internal air(same as balance 4: NTYPE 961)

[kJ/hr]


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Surface Outputs corresponding to Balance 903 (see 5.2.3.5.3):


NTYPE930

B3_QBALBAL 3: solar balance for one external windowshould be always 0

[kJ/hr]

NTYPE931

B3_QSEXTBAL 3: total external solar radiation on theexternal windows including frame

[kJ/hr]

NTYPE932

B3_QBESHDBAL 3: solar blocked due to external shadingdevices of external window

[kJ/hr]

NTYPE933

B3_QBFRMBAL 3: solar blocked due to frame of externalwindow of a zone

[kJ/hr]

NTYPE934

B3_QBREFGBAL 3: solar blocked due to reflection ofglazing of external window

[kJ/hr]

NTYPE935

B3_QBABSGBAL 3: solar blocked due to absorption onglazing of external window (only absorbed fromprimary solar radiation on this window)

[kJ/hr]

NTYPE936

B3_QBRISHDBAL 3: solar blocked due to reflection oninternal shading device (only shortwaveradiation included)

[kJ/hr]

NTYPE937

B3_QBLWISHDBAL 3: solar blocked due to reflection oninternal shading device (part which is absorbedand then going out only longwave)

[kJ/hr]

NTYPE938

B3_QSHFPR

BAL 3: secondary heat flux of external window

only primary solar no reflected radiation orradiation through other windows included

[kJ/hr]

NTYPE939

B3_QSTRNSBAL 3: short wave transmission throughexternal window to zone

[kJ/hr]

NTYPE940

gtot total g-value (SHGC) of external window[kJ/hr]

NTYPE941

fc_Eshade shading coefficient of external shading[kJ/hr]

NTYPE942 gframe g-value (SHGC) of frame of external window

[kJ/hr]

NTYPE943

gglas g-value (SHGC) of glas of external window[kJ/hr]

NTYPE944

fc_Ishade shading coefficient internal shading[kJ/hr]


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NTYPE945

AI angle of incidence for window balance[kJ/hr]

Zone Outputs corresponding to Balance 904 (see 5.2.3.5.4):


NTYPE950

B4_QBALBAL 4: energy balance for zone should bealways close to 0

[kJ/hr]

NTYPE951

B4_DQAIRdt BAL 4: change of internal energy of zone[kJ/hr]

NTYPE952

B4_QHEATBAL 4: power of ideal heating(convective+radiative)

[kJ/hr]

NTYPE953 B4_QCOOL BAL 4: power of ideal cooling

[kJ/hr]

NTYPE954

B4_QINF BAL 4: infiltration gains[kJ/hr]

NTYPE955

B4_QVENT BAL 4: ventilation gains[kJ/hr]

NTYPE956

B4_QCOUP BAL 4: coupling gains[kJ/hr]

NTYPE957

B4_QTRANSBAL 4: transmission into the wall from innersurface node

[kJ/hr]

NTYPE958

B4_QGINT BAL 4: internal gains (convective+radiative)[kJ/hr]

NTYPE959

B4_QWGAIN BAL 4: wall gains[kJ/hr]

NTYPE960

B4_QSOLBAL 4: absorbed solar gains on all insidesurfaces of zone

[kJ/hr]

NTYPE961

B4_QSOLAIR

BAL 4: convective energy gain of zone duetransmitted solar radiation through externalwindows which is transformed immediately intoa con. heat flow to internal air

[kJ/hr]


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Surface Outputs for walls corresponding to Balance 906 (see 5.2.3.5.6)


NTYPE972

B6_BALBAL 6: energy balance for a wall should bealways 0

[kJ/hr]

NTYPE973

B6_DQWALLdt BAL 6 : change of internal energy of wall[kJ/hr]

NTYPE974

B6_QCOMIBAL 6 : combined heat flux to inside (going intozone+; going into wall -)

[kJ/hr]

NTYPE975

B6_QCOMOBAL 6 : combined heat flux to outside (going tooutside-; going into wall +)

[kJ/hr]

NTYPE976

B6_QRADGIBAL 6 : Total radiative gains for inner surfacenode

[kJ/hr]

NTYPE977

B6_QRADGOBAL 6 : Total radiative gains for outside surfacenode

[kJ/hr]

NTYPE978

B6_QALGBAL 6 : Total energy gains by an active layer ora chilled ceiling (heating -; cooling +).

[kJ/hr]


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Airnode Outputs corresponding to Balance 907 (see 5.2.3.5.7 )


NTYPE980

B7_MWBALBAL 7: moisture balance of an airnode shouldbe always 0

[kg/hr]

NTYPE981

B7_MDWAIRBAL 7: change of water stored in the air ofairnode

[kg/hr]

NTYPE982

B7_DMWBUFBAL 7: change of water stored in the surfacesof airnode for the detailed humidity

[kg/hr]

NTYPE983

B7_MWINF BAL 7: water gain of zone due to infiltration[kg/hr]

NTYPE984

B7_MWVENT BAL 7: water gain of zone due to ventilation[kg/hr]

NTYPE985

B7_MWCOUP BAL 7: water gain of zone due to coupling[kg/hr]

NTYPE986

B7_MWIGAIN BAL 7: water gain from internal loads[kg/hr]

NTYPE987

B7_MWHUMBAL 7: water gain due to ideal humidification ofheating type

[kg/hr]

NTYPE988

B7_MWDHUMBAL 7: water loss due to ideal dehumidificationof cooling type

[kg/hr]


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5.2.3.5. Balanc e Outp uts

5.2.3.5.1. B ALANCE 1 - S OLAR B ALANCE FOR Z ONES (NTYPE 901)

This Balance shows how much solar radiation is blocked how much is entering the zoneand how much is exchanged with other zones. This balance is printed always for all zones in onefile (called SOLAR_ZONES.BAL) if NTYPE 901 was selected in the output manager for one zone.

B1_QBAL = B1_QSEXT + B1_QSADJ - B1_QBREFG - B1_QBABSG -

B1_QBFRM - B1_QBESHD - B1_QSLOSS - B1_QSGWIN -

B1_QBRISHD - B1_QISHCCI - B1_QSGWALL

+ B1_QSOLAIR [kJ/hr]

Eq. 5.2.3-1

Balance:

B1_QBAL solar balance for one zone should be always 0.

Maximum possible Gains:

B1_QSEXT total external solar radiation on all windows of one zone including frame

B1_QSADJ solar gains due to exchange with adjacent zones (gains +; Losses -). Includingmultiple refection.

Blocked Gains:

B1_QBREFG solar blocked due to reflection of glazing of all windows of a zone

B1_QBFRM solar blocked due to frames of all windows of a zone. Secondary heat flux intozone from absorbed solar on external surface of frame is not included.

B1_QBESHD solar blocked due to external shading devices of all windows of a zone

B1_QBABSG solar blocked due to absorption on glazing of all external windows (only absorbedgains not entering the zone)

B1_QBRISHD solar blocked due to reflection on internal shading devices of all windows of azone

Losses:

B1_QSLOSS solar radiation leaving zone through external windows of zone (excluding solarreflected by internal shading device)

Gains of zone:


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B1_QSGWIN Absorbed solar gains on all windows of zones going inside (secondary heatfluxfor total window including frame and internal shading device without CCISHADEPart)

B1_QISHCCI Absorbed on all internal shading devices of zone and directly transferred to theairnode by ventilation (CCISHADE).

B1_QSGWALL absorbed solar radiation on all walls of zone.

B1_QSOLAIR convective energy gain of zone due transmitted solar radiation through externalwindows which is transformed immediately into a con. heat flow to internal air.(same as B4_QSOLAIR)

5.2.3.5.2. B ALANCE 2 - S OLAR B ALANCE FOR S UM OF ALL Z ONES (NTYPE 902)

This balance is the same as Balance 1 but all values for all zones are summed up together. IfNTYPE 902 was selected in the output manager for one zone, this balance is printed in one file

called SOLAR_TOT.BAL.

5.2.3.5.3. B ALANCE 3 - S OLAR B ALANCE FOR E XTERNAL W INDOW (NTYPE 903)

This Balance shows how much solar radiation is blocked and how much is entering thezone through a EXTERNAL window. If NTYPE 903 was selected in the output manager, thisbalance will be printed for all selected external windows in one file each (calledSOLAR_WIN_XXX.BAL). Due to the aim of this balance is to show the performance of a windowand its shading devices only the solar radiation entering a external window is taken into account.Reflected radiation from the room or solar radiation entering through other windows is excludedfrom this balance.

B3_QBAL = B3_QSEXT - B3_QBESHD

. - B3_QBFRM - B3_QBREFG - B3_QBABSG

. - B3_QBRISHD - B3_QBLWISHD

. - B3_QSHFPR - B3_QSTRNS [kJ/hr]

Eq. 5.2.3-2


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Balance:

B3_QBAL solar balance for one external window should be always 0.

Maximum possible Gains:

B3_QSEXT total external solar radiation on the external windows including frame

Blocked Gains:

B3_QBREFG solar blocked due to reflection of glazing of external window

B3_QBFRM solar blocked due to frame of external window of a zone.

B3_QBESHD solar blocked due to external shading devices of external window

B3_QBABSG solar blocked due to absorption on glazing of external window (onlyabsorbed from primary solar radiation on this window)

B3_QBRISHD solar blocked due to reflection on internal shading device (onlyshortwave radiation included)

B3_QBLWISHD solar blocked due to reflection on internal shading device (part which isabsorbed and then going out only longwave)

Gains of zone:

B3_QSHFPR secondary heatflux of external window only primary solar no reflectedradiation or radiation through other windows included.

B3_QSTRNS short wave transmission through external window to zone

Out of these parts the performance of the window and its shading devices can be calculated:

gtot = (B3_QSTRNS + B3_QSHFPR) / B3_QSEXT

gtot = fc_Eshade * gframe * gglas * fc_ishade Eq. 5.2.3-3


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5.2.3.5.4. B ALANCE 4 - E NERGY B ALA NCE FOR Z ONES (NTYPE 904)

The system boundary for this energy balance includes the inside surface node of allsurfaces of a zone. Due to this also all radiative heat fluxes appear in this balance. This isdifferent from the balance shown in Section 5.4.1.1 which could only treat the Convective Heat

Flux to the Air Node. However the system boundary doesn‟t include the inside of a wa ll so theenergy of an active layer as well as the stored energy of walls is not part of this balance but of thedetailed balance for surfaces (see 5.2.3.5.6). If NTYPE 904 was selected in the output manager,this balance will be printed for all zones in one file (called ENERGY_ZONES.BAL).

B4_QBAL =- B4_DQAIRdt + B4_QHEAT - B4_QCOOL + B4_QINF

+ B4_QVENT + B4_QCOUP + B4_QTRANS

+ B4_QGINT + B4_QWGAIN + B4_QSOL

+ B4_QSOLAIR [kJ/hr]

Eq. 5.2.3-4

Balance:

B4_QBAL energy balance for one zone should be always closed to 0. In order to save timethe matrix of TYPE 56 is not inverted all the time, but only if the error is less thana certain tolerance. Due to this fact the energy balance of the zone isn‟t always 0.

B4_DQAIRdt change of internal energy of zone (calculated with capacitance of air +additionalcapacitance which might be added in TRNBuild)

B4_QHEAT power of ideal heating (convective+radiative)

B4_QCOOL power of ideal cooling

B4_QINF infiltration gains

B4_QVENT ventilation gains

B4_QCOUP coupling gains

B4_QTRANS transmission into the wall from inner surface node (might be stored in the wall,going to a slab cooling or directly transmitted)

B4_QGINT internal gains (convective+radiative)

B4_QWGAIN wall gains

B4_QSOL absorbed solar gains on all inside surfaces of zones (NOTE: This gain isn‟t equalto Balance 1, because the absorbed solar gains of the inside surface of allwindows are taken into account. These absorbed gains may go inside or outside.For Balance 1, the absorbed gains on the inside and outside node going insideare used.)

B4_QSOLAIR convective energy gain of zone due transmitted solar radiation through externalwindows which is transformed immediately into a con. heat flow to internal air.


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5.2.3.5.5. B ALANCE 5 - E NERGY B ALA NCE FOR S UM OF ALL Z ONES (NTYPE 905)

This balance is the same as Balance 4 but all values for all zones are summed up together. IfNTYPE 905 was selected in the output manager for one zone, this balance is printed in one filecalled ENERGY_TOT.BAL.

5.2.3.5.6. B ALANCE 6 - E NERGY B ALANCE FOR SURFACES (NTYPE 906)

This Balance shows the detailed energy balance of a surface. If NTYPE 906 was selected in theoutput manager, this balance will be printed for all selected walls in one file each (calledENERGY_SURF_XXX.BAL).

B6_BAL = - B6_DQWALLdt – B6_QCOMI + B6_QCOMO + B6_QRADGI

+ B6_QRADGO - B6_QALG [kJ/hr]Eq. 5.2.3-5

B6_BAL energy balance for a surface should be always 0.

B6_DQWALLdt change of internal energy of surface

B6_QCOMI combined heat flux to inside (going into zone+; going into wall -)

B6_QCOMO combined heat flux to outside (going to outside-; going into wall +)

B6_QRADGI Total radiative gains for inner surface node (including solar gains, rad.internal gains wallgains and rad. heating see 5.4.1.3)

B6_QRADGO Total radiative gains for outside surface node (including solar gains, rad.internal gains wallgains and rad. heating see 5.4.1.3)

B6_QALG Total energy gains by an active layer or a chilled ceiling (heating -;cooling +).


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5.2.3.5.7. B ALANCE 7 - MOISTURE BA LANCE FOR ZONES (NTYPE 907)

This Balance shows the moisture balance for all zones separately. Note: if the humidity

ratio reaches 100 % with an on going positive water gain to the zone. This will still lead to aincreasing amount of water stored in the air while actually there would be water drops somewhereon surfaces.

B7_MWBAL = B7_MDWAIR + B7_DMWBUF - B7_MWINF - B7_MWVENT -

B7_MWCOUP - B7_MWIGAIN - B7_MWHUM +

B7_MWDHUM [kJ/h]

Eq. 5.2.3-6

B7_MWBAL moisture balance for each zone should be always 0.

B7_MDWAIR change of water stored in the air of zone

B7_DMWBUF change of water stored in the surfaces of zone for the detailed humiditymodel (sum of deep and surface storage)

B7_MWINF water gain of zone due to infiltration

B7_MWVENT water gain of zone due to ventilation

B7_MWCOUP water gain of zone due to coupling

B7_MWIGAIN water gain from internal loads

B7_MWHUM water gain due to ideal humidification of heating type

B7_MWDHUM water loss due to ideal dehumidification of cooling type

5.2.3.5.8. B ALANCE 8 - M IOSTURE B ALA NCE FOR S UM OF ALL Z ONES (NTYPE 908)

This balance is the same as Balance 7 but all values for all zones are summed up together.

5.2.3.5.9. B ALANCE 9 – S UMMARY

This balance is automatically printed for all building simulations (SUMMARY.BAL). The first part

of this summary balance is based on balance 4 - energy balance per zone where all values pertime step are summed over the total simulation time.

The second part of this summary is based on balance 6 – energy balance for surfaces where allvalues per time step are summed over the total simulation time.

For a yearly simulation the integrated internal energy change of the wall this values should besmall because the initial conditions are close to the final conditions of the simulation.


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5.2.4. The Zone Wind ow

The ZONE window contains all information describing a thermal zone of the building as shown inFigure 5.2.4-1. To add a new zone, click on ADD ZONE under the ZONES menu. An active zonecan be deleted by clicking on DELETE ACTIVE ZONE under the ZONES menu.

In addition, you may use the zone manager by a right mouse click. For opening an existing zoneclick on the zone name within the zone manager. Since Windows 95 and 98 have a bugconcerning the resource handling you may have up to 6 zone windows open at once only.

Figure 5.2.4-1: The ZONE window

Since Version 17, a thermal zone may consist of one or more airnodes. Airnodes can be movedfrom one zone to another for creating multi-airnode zones. This new feature simplifies thesimulation of stratification effects within an atria or double facades.

The data describing an airnode can be divided into four main parts:

a) the required REGIME DATA,

b) the WALLs of the airnode

c) the WINDOWs of the airnode and

d) optional equipment data and operating specifications including INFILTRATION,VENTILATION, COOLING, HEATING, GAINS and COMFORT.

In addition, geometry modes and radiation modes are defined for zones (not airnodes!)

When entering data for a new zone, it is recommended that the user proceeds in the order shownabove.


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5.2.4.1. Inpu t of the Requ ired Regime Data

The following data is entered in the REGIME DATA portion for each airnode:

• volume volume of the air within the airndoe

• capacitance total thermal capacitance of airnode air plus that of any mass not

considered as walls (e.g. furniture,...)

• initial temp. initial temperature of the airnode air

• initial rel. humidity initial relative humidity of the airnode air

• humidity model a simple (capacitance) or detailed (buffer storage) model

In order to simplify the input, default values for all parameters except the VOLUME are provided.The CAPACITANCE will be automatically set to a default value of 1.2*VOLUME. However, it isrecommended that the user check the default values carefully and to adjust them if necessary.

In order to model the buffer effect of humidity within a zone, two humidity models are available.The simple humidity model represents an effective capacitance model in which only the humiditycapacitance ratio must be specified. The humidity capacitance ratio entered accounts for humiditycapacitance of the air plus any other mass within the zone.

In addition to the simple model, a more detailed moisture capacitance model has been addedsince TRNSYS 14.2. This model describes a separate humidity buffer divided into a surface anda deep storage portion. Each buffer is defined by three parameters as shown in Figure 5.2.4-2. The exchange coefficient of the surface buffer storage describes the humidity exchange betweenthe zone air and the surface buffer. The exchange coefficient of the deep buffer surface describesthe humidity exchange of the surface and the deep buffer storage. See the main TRNSYSReference Manual for a detailed description of this model.

Figure 5.2.4-2: The DETAILED HUMIDITY MODEL window


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5.2.4.2. Inpu t of Walls

The information about WALLs within a zone is displayed in the left lower part of the AIRNODEwindow. Here, the user can add, delete or edit the walls of an AIRNODE . A box in the upper partprovides an overview of all defined walls. By clicking on a wall within this overview box, the

definition of the selected wall is displayed below and can be edited. To delete a defined wall,select the desired wall in the overview box and click on the DELETE button.

Figure 5.2.4-3: Adding a new wall

To add a new wall, click on the ADD button below the overview box and a new undefined wall isadded as shown in Figure 5.2.4-3. Now it is necessary to define this new wall:

• WALL TYPE

The wall type can be specified by using the pull-down menu on the right side. This menu offersthe option of defining a new wall type, selecting a wall type out of a library, defining a wall withcoldbridge effect, or selecting a previously defined wall type. The first three options are explainedlater in detail. The name of the selected wall type appears in the display box.


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• AREA

The entered area of the wall should include the area of all windows within the wall. For internalwalls, the area should be doubled, because the front as well as the back surface of the wall isexposed to the zone.

• CATEGORY

The wall category is set to EXTERNAL by default. To change the wall category, use the pull-downmenu on the right side. The following wall categories are available:

EXTERNAL an exterior wall

INTERNAL a wall within an airnode

ADJACENT a wall that borders another airnode

BOUNDARY a wall with boundary conditions

• GEOSURF

Explicit distribution factors can be defined by the user for the distribution of direct solar radiationentering a zone (not airnode!). The value of GEOSURF represents the fraction of the totalentering direct solar radiation that strikes the surface. The sum of all values of GEOSURF is notallowed to exceed 1 within a zone. The movement of the sun patches within a zone can bemodeled by defining a SCHEDULE or an INPUT. The default value of GEOSURF is 0. If the sumof values within a zone is zero, the direct radiation is distributed the same way as the diffuseradiation (by absorptance weighted area ratios). Note: In TRNSYS 17 a detailed radiation modefor distributing beam radiation through external windows depending on the geometry and currentsun position is available (for further information see 5.2.4.12 radiation modes.)

• SURFACE NUMBER

The surface number is a unique number used for surface identification. The number is generatedby TRNBUILD automatically and displayed behind the edit box of GEOSURF in blue.

• WALL GAIN

With wall gain an energy flux to the inside wall surface can be defined

The display of the other required input data adjusts automatically based on the window category.

For the “view factor to the sky” (fraction of the sky to the celestrial hemisphere seen by the wall) avalue ≤ 1 must be entered (i.e. 1 for a horizontal surface, 0.5 for a vertical surface withunobstructed view). The value is used as a weighting factor between “ground” and skytemperature for the longwave radiation exchange.


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5.2.4.2.1. T HE W ALL L IBRARY

Before creating a new wall type, it is recommended that the user first check the wall library byselecting LIBRARY from the WALL TYPE pull-down menu within the ZONE window. The walllibrary window opens as shown in Figure 5.2.4-4.

Figure 5.2.4-4: The WALL LIBRARY window

Here, the user can use the mouse to select the wall construction from two different libraries: aprogram library and a user library. If the German library version is selected under SETTINGSfrom the OPTIONS menu, typical wall constructions according to VDI 2078 are available. If theUnited States version is selected, 144 wall constructions according to the ASHRAE Standard areprovided.

The definition of walls can be loaded from standard libraries as can be seen in the upper part or

from user defined libraries. In both cases, path and file name can be changed from wall to wall byuse of the interactive file dialog boxes.

A default wall type name is given by the program after the selection, but can be changed to amore meaningful one. The „front‟ and „back‟ default values for the solar absorptance andconvective heat transfer coefficient correspond to the internal surface and external surface,respectively, for both vertical and horizontal external walls. Thus, they need to be adjusted basedon the desired wall category.


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Figure 5.2.4-5: Heat transfer coefficient definition

While a constant heat transfer coefficient will be sufficient in most cases, it is possible to chooseinternal calculation if desired. You will have to select whether the wall is a floor a ceiling or verticalto fit the appropriate heat transfer mechanism. See Section 5.2.3.2 for further information.

5.2.4.2.2. D EFINITION OF A N EW W ALL T YPE

To define a new wall type, select NEW from the pull-down menu of WALL TYPE within the ZONEwindow and a window as shown in Figure 5.2.4-6 will pop up. Besides entering a unique name forthe wall type, the solar absorptance, and the convective heat transfer coefficient, the user mustspecify the construction of the wall type. The construction is specified by a series of layers

starting from the “inside” surface (front) of the wall to the “outside” (back). The user can create anew layer, select a layer from a library or select a previously defined layer by using the right boxand the arrow buttons. After entering the thickness the selected layer appears in the left box. Thethickness of a layer in the left box can be edited by a double-click. TRNBUILD calculates the totalwall thickness as well as a standard U-value. This standard U-value is determined with combinedheat transfer coefficients of 7.7 W/ (m² K) inside and 25 W/ (m² K) outside.

Figure 5.2.4-6: The NEW WALL TYPE window


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Before defining a new layer, the user should first check the provided layer libraries by clicking onLIBRARY in the layer box. The layer library window opens as shown in Figure 5.2.4-7. Here, theuser can use the mouse to select layers from two different libraries: a program library and a userlibrary. If the German library version is selected under SETTINGS from the OPTIONS menu, over500 different layers according to DIN4108 are available. If the United States version is selected,over 500 different layers are also available. A default layer name is given by the program, but it isrecommended that the user change it into a more meaningful one. Finally, the user must specifythe thickness of the layer.

If the user defines a new layer, the definition window for a new layer opens (see Figure 5.2.4-8).The user can now enter the corresponding material properties for the layer. To save the newlydefined layer to the user library, press the SAVE TO LIBRARY button before clicking on the OKbutton. Henceforth, the saved layer will be available for other projects and will appear in thepreviously described layer library window.

Figure 5.2.4-7: The LAYER LIBRARY window

Again, path and file name for program lib or user lib might be changed for each selected layer byuse of file dialog boxes.


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For the definition of a new layer there are 4 options:

• Massive: this is the most common one usually used in all constructions

• Massless: only used when TRNBuild is not able to create the transfer functions of awall with only massive layers. In that case this layer type is used for very

thin layers where the thermal mass can be neglected

• Active: used for concrete core cooling and heating, capillary tube system and forfloor heating and cooling systems (see Section 0)

• Chilled ceiling: chilled ceiling panel decoupled from the rest of the wall due to insulationor airspace (see Section 5.2.4.2.4)

Figure 5.2.4-8: The NEW LAYER window


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In addition to the wall construction coefficients of the solar absorptance is required. The solarabsorptance coefficient depends on the properties of the wall finish.

Outside surface solar absorptance coefficient

Roof tile, colored ceramic, slate, concrete

• rough surface, dark red 0.75 ... 0.80

• smooth surface, dark color 0.70 ... 0.75

• asbestos concrete 0.60 ... 0.65

Roof coating

• green 0.60 ... 0.65

• aluminum color 0.60 ... 0.65

• light grey, bright 0.30 ... 0.40

• white, smooth 0.20 ... 0.25

Exterior wall

• smooth surface, dark color 0.70 ... 0.75

• rough surface, medium bright color yellow and yellow red clinker, brick)

0.65 ... 0.70

• smooth surface, medium bright color (chalky sandstone, asbestos concrete)

0.60 ... 0.65

• rough surface and white color 0.30 ... 0.35

• smooth surface and white color 0.25 ... 0.30

Metallic surface

• zinc sheet, aged and dirty 0.75 ... 0.80

• aluminum, matted surface 0.50 ... 0.55

• aluminum color 0.35 ... 0.40

• bright and polished surface 0.20 ... 0.25

Note: In contrast to previous versions, the solar absorptance coefficient should not beused for solar radiation distribution. The distribution factor GEOSURF has beenimplemented for that behalf.

Since Version 17, the longwave emission coefficient can be defined. The default value is 0.9.Note. The coefficients of inside surfaces are used by the detailed longwave radiation mode only!If the standard or simple model is selected the entered values are ignored and set to 0.9.


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Finally, the convective heat transfer coefficient (without a radiative part!) must be defined.Common values are:

• inside: 11 kJ / h m² K

• outside: 64 kJ / h m² K

Figure 5.2.4-9: Heat transfer coefficient definition

While a constant heat transfer coefficient will be sufficient in most cases, it is possible to choose

internal calculation for any wall within a zone if desired. You will have to select whether the wall isa floor a ceiling or vertical to fit the appropriate heat transfer mechanism. See Chapter 5.2.3.2


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Properties for further information.

Note: The automatic calculation of heat transfer coefficients is only appropriate for insidesurfaces. Therefore it can not be used for outside surfaces of external or boundary walls.For this kind of surfaces a user defined correlation may be defined taking into accountalso wind influence.

Documents

Type 56 05-MultizoneBuilding