Simulation Driven Green Building Design - caeai.com · PDF fileSimulation Driven Green Building Design ... • ANSYS simulation tools are used in all of the above areas • Application

Simulation Driven Green Building Design

© 2009 ANSYS, Inc. All rights reserved. 1 ANSYS, Inc. Proprietary© 2009 ANSYS, Inc. All rights reserved. 1 ANSYS, Inc. Proprietary

Simulation for Green Technology

• Green Technology is composed of several key thrusts

– Pollution Reduction

– Renewable Energy & Fuels

– Energy Efficiency

– Indoor Air Quality

© 2009 ANSYS, Inc. All rights reserved. 2 ANSYS, Inc. Proprietary

– Indoor Air Quality

– Green Building Design

• ANSYS simulation tools are used in all of the above areas

• Application of ANSYS simulation tools (related to Airflow Modeling) in Green Building Design is briefly highlighted here

What is Airflow Modeling

• Numerical approach to solve the complex governing equations of airflowcontinuity / momentum / energy / contaminant transport

• Requires a computer model of the space -> mesh– not all features of the geometry are relevant to airflow


• Requires specification of boundary conditionsflows / heat sources / contaminant sources / wall BCs

Airflow Modeling & Contaminant

Transport in Ramsis VII Tomb


Courtesy of: Cairo University, Egypt

How Airflow Modeling helps Engineers with

Green Building Design

– Help optimize energy performance (1-19 LEED points)

– Design on-site renewable energy (1-7 LEED points)

– Design to control indoor chemical and pollutant sources (1 LEED

• Engineers benchmark designs using the LEED Green Building Rating System


– Design to control indoor chemical and pollutant sources (1 LEED point)

– Design to comply with ASHRAE Standard 55-2004, for thermal comfort (1 LEED point)

– Design HVAC system (mechanical or naturally ventilated) to provide minimum IAQ performance complying with ASHRAE 62.1-2007 (Required – No LEED points)

– Design for ETS control (Required – No LEED points)

• Airflow modeling assists in the process of developing and evaluating design concepts as well as contributes to the evidence that a proposed design meets various rating criteria

Innovation for Demanding Applications

• Design objective was to create

William Jefferson Clinton Museum

Little Rock, Arkansas

Courtesy of Flack & Kurtz


• Design objective was to create stratified layer of air with conditions in human comfort zone

• Large cooling load due to solar radiation, specialty lighting, and interactive display equipment

• Design included radiant floor, underfloor air distribution, and jet supply diffusers with various supply temperatures

Use Airflow Modeling to Support

LEED Certification Process


• Simulations were performed to study the interaction of the various systems

• To determine the optimum operating conditions for the air flow systems during regular occupancy

• to verify the ventilation effectiveness in support of a LEED™ credit

Supply Airflow PathlinesWilliam Jefferson Clinton Museum

Little Rock, ArkansasCourtesy of Flack & Kurtz

Use Airflow Modeling to Support

LEED Certification Process

“We have used ANSYS software for quite a few years, but just within the past two years we have

Great River Energy Corporate HQMaple Grove, Minnesota

Courtesy of Dunham Associates


John Costello, LEED AP

Dunham Associates

years, but just within the past two years we have been using it more often for many different projects. Simulation results assist us in the process of developing and evaluating design concepts as well as contribute to the evidence that a proposed design meets various rating criteria. Moreover, we use the software to produce visualizations for marketing purposes to enhance our communication with prospective clients. I don't see our use of this tool letting up any time soon.”

Colored contours of Thermal Comfort in a conference room predicted for a particular ventilation system design

Atrium Design for Energy Efficiency

& Comfort


Courtesy of:Architectural Energy CorporationEnergy and Sustainable Design ConsultantsBoulder, CO

National Museum for the Marine CorpsQuantico, Virginia

Temperature contours

Natural Ventilation

& Solar Radiation

Proposed Expansion of

Phipps Conservatory and Botanical Gardens

Pittsburgh, Pennsylvania


Simulation of naturally ventilated tropical rain forest building showing

• airflow pathlines

• air temperature

• solar shading

Courtesy of:IKM Incorporated ArchitectsPittsburgh, PA

Architectural Energy CorporationEnergy and Sustainable Design ConsultantsBoulder, CO

Airflow Simulation in Design

of Green Buildings

• Award winning entry in U.S. Green Building Council (USGBC) Design Competition modeled using CFD software from Ansys

• Entries required to meet


• Entries required to meet requirements for LEED Platinum Rating plus target budget of <$100 per square foot.

• Natural ventilation design performance assessed through airflow simulation

Proposed Addition to facility for the Pittsburgh Project

Courtesy of OWPP

CFD Assessment of

Natural Ventilation Design

• Simulation allows exploration of energy efficiency concepts that might otherwise be deemed unrealizable


• Velocity Vectors and Temperature Contours in Proposed Design

unrealizable

Courtesy of OWPP

Allianz Stadium in Munich

• Specially built for the World Cup

• Holds 70,000 spectators and the largest car park in Europe (10,000 cars) underneath it


• Simulation was used by VTD GmbH to design the stadium with respect to– Airflow requirements over the

stadium– Thermal comfort for the crowd– Airflow over the turf for optimal

grass growing conditions– Fire/smoke management– Parking garage ventilation

Allianz Stadium

Simulated Airflow Patterns

External


Internal

• Occupant thermal comfort and indoor air quality• Predicting room conditions:

– Air velocity, temperature– Relative humidity, thermal radiation– Toxins

• Assessment of a variety of comfort criteria– Combined with information about occupant activity and clothing

• Impact of heat loss through the structure, including solar gain effects

Thermal Comfort and Ventilation


• Impact of heat loss through the structure, including solar gain effects• Testing effectiveness of novel strategies and concepts:

– Natural and mixed ventilation– Minimizing energy consumption

Courtesy of Olof Granlund Oy

Hodynka Arena in Moscow

Courtesy of

Home of the 2007 IIHF World

Championships

Supply jetsDisplacement Diffuser


• Simulation was used to– Determine the best HVAC systems– Thermal comfort for the crowd– Fire/smoke management

• Facility employs combined displacement ventilation and mixing airflow from supply jets

• Facility has multiple uses

Temperature during Summer Hockey Game

Air Velocity for Mixing Airflow from Roof Zone

Temperature during Summer Concert

Diffuser

Yoyogi National Stadium in Japan

• Multi-use stadium– Swimming competitions– Concerts

• Different ventilation strategies– Active/inactive supply

diffusers– Different airflow patterns –


Yoyogi National Stadium with its double-crescent roof design

– Different airflow patterns – Still able to provide

temperature uniformity

Computational mesh

particle traces colored by temperature

Airflow & Thermal Comfort

in a Theater


Courtesy of McCracken & Lopez, P.A.

Airflow & Thermal Comfort in

the Budapest Opera House

• Built in 1884 and original ventilation was via natural ventilation through vents under seating area

• Renovated several times over the years with


over the years with mechanical ventilation and air conditioning systems introduced

• Separate ventilation system for the stage area

• Used airflow modeling as part of an HVAC assessment of the building

• CFD results showed

• Poor ventilation in the

Airflow & Thermal Comfort in

the Budapest Opera House


Pathlines colored by temperature show differences of 5oC or less between seating area

and orchestra pit

• Poor ventilation in the orchestra pit

• Thermal anomalies in the balcony

• Airflow study being used in the reconstruction and modernization of the Opera House ventilation system

Welsh Assembly (BDSP)


• Aim:– Optimize ventilation configuration

with regard to thermal comfort and energy consumption

• Results shown here: Fan-assisted buoyancy-driven ventilation

Swiss Re Building - London

• Simulations assessed the buildings fluid and thermal performance– Displacement ventilation– Chilled floors– The cooling dome–

First Sustainable Design Building in London


– The cooling dome– Solar heating– Pedestrian and worker comfort

Simulated airflow on one floor with windows open

CAD model of several floors

Greenwich Millennium DomeGreenwich Millennium Dome


• CFD done by CFX , began in 1998, commissioned by NMEC & Buro Happold

• Ventilation + fire• Wind boundary conditions at dome

roof provided by Buro Happold

Floor Temperature & Thermal Stratification in

a Conference Room with Displacement

Ventilation

� 250 cfm per diffuser� 64 oF supply temp

� 150 cfm per diffuser� 56 oF supply temp


• Project showed ability of the ventilation system to circulate fresh air throughout the facility

Parking Garage Ventilation


• Ventilation system for an enclosed 5-level parking garage– Fresh air through openings– Axial circulating fans on each

level– Centrifugal exhaust fans on

each level

Wind Engineering

• Response of the building to its environment as well as the response of the environment to the building

• Understand the aerodynamics of a structure and the resulting pressure map on its surface

• Analysis of the behavior and stability of the construction under various weather conditions


construction under various weather conditions

• Impact on pedestrian comfort and safety

• In urban and non-urban settings, address: – Environmental and safety issues– Dispersion of gases and aerosols

Some pictures courtesy of Building Design Partnership Ltd

Dispersion of exhaust discharge and its impact on the surrounding

buildings to ensure the design proposal met current regulations

and standards

Pressure map on a building with flow pathlines around it

BullRing Shopping & Leisure Complex

- Birmingham, England

•


• Simulations assessed performance of proposed plant arrangement

• Identified if exhaust air was re-circulated to fresh air intakes

• Aided finding the appropriate solution for plant and intake positioning

Bishopsgate Tower - London

Pressures on the surfaces of Bishopsgate Tower and some surrounding buildings


• External wind simulation • Computed building surface pressure

distribution used for wind loading analyses

Courtesy of Hilson Moran, London, UK

CFD Modelling of Regional Flow

Patterns near Cape Shopping Centre

Surface Mesh


Courtesy of:Stephan Schmitt & Thomas Kingsley

Qfinsoft, SA

Surface PressuresSurface Pressures

temperature contours

ANSYS Simulation Software Products are

Effective Green Building Design Tools

• Better understand alternatives to mixing ventilation• Streamline diffuser placement• Optimize supply flow rates and supply temperatures• Investigate design performance ahead of time

• Save time and money by quickly and accurately exploring alternate designs

• Demonstrate to clients how different ventilation strategies work


air velocity vectors

contours

Naturally Ventilated Shopping GalleriaCourtesy of Mechanical Design Associates

Documents

Simulation Driven Green Building Design - caeai.com · PDF fileSimulation Driven Green Building Design ... • ANSYS simulation tools are used in all of the above areas • Application