AHEF.120.MD. ENERGY EFFICIENCY AUDIT GUIDE FOR CHP and HOB

Waste heat recovery

Waste heat recovery

Contract No 2011/278827

A project within the INOGATE Programme

Implemented by:Ramboll Denmark A/S (lead partner)

EIR Development Partners Ltd.The British Standards Institution

LDK Consultants S.A.MVV decon GmbHICF International

Statistics DenmarkEnergy Institute Hrvoje Požar

June 2015

INOGATE Technical Secretariat and Integrated Programme in support of the Baku Initiative and the Eastern Partnership energy objectives

Document title

Document status Draft 0.1

Name Date

Dr. Albin ZSEBIK and Daniel NOVAK 09.06.2015

Template Heat losses 1.: Heat losses analysis in the DH system network, supplied from HOB Sud

Prepared by

Checked by

Approved by

This publication has been produced with the assistance of the European Union. The contents of this publication are the sole responsibility of the authors and can in no way be taken to reflect the views of the European Union.

Table of Contents

Introduction

Keywords

Waste heat recovery:

1. Project sheet2. Input data

3. Technical calculation4. Financial calculation

5. Used formulas6. X-steam Table Nr.1.7. X-steam Table Nr.2.

advantages of waste heat recovery, application, saving potential, simple payback period

Waste heat is heat, which is generated in a process by way of fuel combustion or chemical reaction, and then "dumped" into the enviroment even though it could still be reused for some useful and economic purpose. Following are equipment options that can recover energy from wasted heat or steam, thereby reducing fuel usage while increasing system efficiency.1. Stack Economizer: Recovers heat from flue gases that would otherwise be wasted, and is used to preheat boiler combustion air or feed water, to heat water for absorption chillers, heating system and domestic water system. 2. Two-Stage Condensing Economizer: Captures heat through both a traditional stack economizer section and a condensing section. One section recovers energy by preheating boiler combustion air or feed-water. The second (condensing) section preheats cool liquid streams, such as make-up water, process water, or domestic water for sinks and showers. 3. One-Stage Condensing Economizer: Saves fuel by preheating virtually any cool liquid stream (e.g., make-up water, process water) by capturing the wasted heat from the boiler stack. It increases the amount of heat recovered by capturing both sensible and latent heat energy. 5. Flash Tank Economizer: Captures high-temperature flash steam and condensate from a non-modulating process load, providing (sensible) heat for make-up water and low-pressure flash steam (latent heat) for the deaerator. This system quickly pays for itself with fuel savings resulting from recycled heat that would otherwise be wasted through exhaust. 6. Blowdown Heat Recovery System: Captures waste heat from the boiler surface blowdown to increase make-up water temperature (sensible heat) going to the feed-water tank. Continuous boiler surface blowdown heat recovery is the most optimized method of controlling total dissolved solids (TDS) levels within the boiler because it captures otherwise wasted energy normally purged to the sewer. These units are available for boilers of all sizes, including multiple boilers.

This Excel sheet:1. Helps to identify the heat in flue gases, which would waste without heat recovery;2. Gives possibility to calculate three stage stack economizer for different purpose, but without condensing of the steam content of the flue gas;3. Calculates the fuel and fuel cost saving gained by the recovered heat;4. Makes basic economical evaluation (calculate simple payback period) based on the given investments costs and;5. Shows example of the projects sheet, where the findings concerning the existing conditions, the recommended actions to improve efficiency and expected results are described.Attention: This file works properly, if the fuel is natural gas, and the boiler is a steam boiler.

ACTION No: ET - 000 - 16Recommended Action – Energy efficiency opportunity

Prepared for SampleReport date:

tel/fax E-mailPrepared by:Checked by:Approved by:

Action name: Installation of flue gas heat recovery heat exchangersArea of the Plant Affected: HOB plant SUD

Findings concerning existing conditions:

Recommended action to improve efficiency:

Expected results – effect of recommendation:

Base line - existing conditions - - - - After recommended action #VALUE! #VALUE! #VALUE!

#VALUE!Total recovered heat [GJ] #VALUE!

COST – BENEFIT ANALYSISProject cost estimate: MDL

Engineering design: 63,539Equipment procurement: 1,258,200Equipment installation: 629,100Equipment commissioning: 629,100Project support: 0Total installing cost: 2,579,939

Recommended implementation schedule:

Content

The flue gas leaves the boilers type xxxxxxxx on high temperature (xxx°C).

Based on the site visit and on the feasibility study No xxxxxxxx the boilers is recommended installation of flue gas heat exchangers for absorption chiller, for heating system and DHW-system. With the heat recovery the exhaust gas temperature can be decrease to the xx °C, and the fuel consumption can be decreased.

Recovered heat for absorption chiller

[GJ/year]

Recovered heat for heating system

[GJ/year]

Recovered heat for DHW

system [GJ/year]

Reduction of fuel

consumption [MDL]

Payback period (simply payback):

Estimated increase in annual (non energy) operations and maintenance cost:

0 2000000 40000000

0.10.20.30.40.50.60.70.8

0.91

7.172

7.5707.969

9.164

9.961

Base

Project cost [MDL]

Payb

ack

perio

d [Y

ear]

Fuel cost [M DL/m3]

0 2000000 40000000

0.10.20.30.4

0.50.60.7

0.80.9

1

7.172

7.570

7.969

9.164

9.961

Base

Project cost [MDL]

Payb

ack

perio

d [Y

ear]

Fuel cost [M DL/m3]

Existing solution:

Preparing measurement plan for a steam boiler:

M1 Combustion airTemperature [°C]

Relative humidity [%]

M2 Fuel consumptionTemperature [°C]

M3 Steam (saturated) Pressure [bar]

M4 Feed waterMass flow rate [t/h]Temperature [°C]

M5 Flue gas

Temperature [°C]Oxygen-content [%]

CO-content [ppm]

M6 Blow-down Mass flow rate [t/h]M7 Boiler-water Conductivity [μS/cm]

Recommended solution:

Fuel flow rate [l/h, t/h, nm3/h]

Conductivity [μS/cm]

Boiler data sheet

General informationBoiler ID./Tag FactoryMfr/Model # HLG 20/12Year built 1965 Serial number Nr. 19650523-15-25Boiler type Fire Tube Heating fluid Steam

Equipment nominal dataSteam generated [t/h] 20Steam pressure [bar] 12

Temp. of saturated steam [°C] 188Temp. of Feed water [°C] 90Reference efficiency [%] 90

Fuel dataBoiler fuel Natural gas

Lower heating value (LHV) 36.62 [MJ/m^3] 40.57 [MJ/m^3]

Chemical composition of fuel0.96 358740.04 64423

0 928870 1225720 0

CO 0 126230 107990 00 00 00 5940 0

Higher heating value (HHV)

CH4

[m3/m3 fuel] Heating value of comp. [kJ/m3]

C2H6

C3H8

C4H10

CmHn

H2

CO2

N2

O2

H2S

H2O

Fire Tube Natural gasWater Tube PB-gas Water (<110°C)Electric Fuel oil Water (>110°C)Natural Draft Coal Steam Forced Draft OtherCondensingOther _________

Profile of operation

Profile of operationPeformance rate [%] Operation time [h/a]

0 26010 020 030 040 40050 100060 155570 429580 125090 0100 0

Check Correct input data <---

Parameters of flue gas

Quantity of flue gasProportion of oxygen in flue gas [%] 3.5

0.9718

Temperature of flue gas [°C] 250

Ambient temperature [°C] 0

Different application for waste heat recovery

Required temperature diff. of heat exchangers [°C] 15

Outlet temp. of hot water (absorption chiller) [°C] 115

Inlet temp. of hot water (absorption chiller) [°C] 100

Outlet temp. of water (heating system) [°C] 80

Inlet temp. of water (heating system) [°C] 60

Outlet temp. of water [°C] 55Inlet temp. of water [°C] 12Reference efficiency [%] 85

Specific heat of flue gas [kJ/(m3∙°C)]

0 20 40 60 80 1000

10002000300040005000

Profile

Performance rate [%]

Ope

arito

n tim

e [h

/a]

0 0.5 1 1.5 2 2.50

50100150200

Different application for recovering waste heat

Recovered heat [GJ/a]

Flue

gas

tem

pera

ture

[°c]

0 0.5 1 1.5 2 2.50

50100150200

Different application for recovering waste heat

Recovered heat [GJ/a]

Flue

gas

tem

pera

ture

[°c]

Financial data

Operations and maintenance costMaintance cost [EUR/a] 100000

Fuel cost [EUR/m3] 0.35MDL exchange rate [1 EUR] 20.97

Project cost estimateEngineering design [EUR] 3,030

Equipment procurement [EUR] 60,000Equipment installation [EUR] 30,000

Equipment commissioning [EUR] 30,000Project support [EUR] 0

Sensitivity

Range of fuel cost [%]

-10-515

25

Rate of increase (project cost) [%] 25

0 20 40 60 80 1000

10002000300040005000

Profile

Performance rate [%]

Ope

arito

n tim

e [h

/a]

0 500000 1000000 1500000 2000000 2500000 3000000 35000000

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1Financial analysis

7.172

7.570

7.969

9.164

9.961

Base

Project cost [MDL]

Payb

ack

perio

d [Y

ear]

Fuel cost [MDL/m3]

Boiler data sheet

General informationBoiler ID./Tag FactoryMfr/Model # HLG 20/12Year built 1965 Serial number Nr. 19650523-15-25Boiler type Fire Tube Heating fluid Steam

Equipment nominal dataSteam generated [t/h] 20Steam pressure [bar] 12

Temp. of saturated steam [°C] 188Temp. of Feed water [°C] 110Reference efficiency [%] 90

Fuel dataBoiler fuel Natural gas

Lower heating value (LHV) 36.62 [MJ/m^3] 40.57 [MJ/m^3]

Chemical composition of fuel0.96 358740.04 64423

0 928870 1225720 0

CO 0 126230 107990 00 00 00 5940 0

37.0

If you have the composition list of fuel, and not the exact heating value, then please copy D32 to B18

Input data in yellow cells.Calculated data in red cells.

Higher heating value (HHV)

CH4

[m3/m3 fuel] Heating value of comp. [kJ/m3]

C2H6

C3H8

C4H10

CmHn

H2

CO2

N2

O2

H2S

H2O

Calc. heating value [MJ/m3]

Profile of operationPeformance rate [%] Operation time [h/a]

0 26010 020 030 040 40050 100060 155570 429580 125090 0

100 0Check Correct input data <---

Fuel consumption

Steam enthalpy [kJ/kg] #VALUE!

Feed water enthalpy [kJ/kg] #VALUE!

Peformance rate [%] Fuel consumption Heat input [MJ]

0 #VALUE!

[m3]

#VALUE!

10 #VALUE! #VALUE!

20 #VALUE! #VALUE!30 #VALUE! #VALUE!

40 #VALUE! #VALUE!

50 #VALUE! #VALUE!

60 #VALUE! #VALUE!

70 #VALUE! #VALUE!

80 #VALUE! #VALUE!

90 #VALUE! #VALUE!100 #VALUE! #VALUE!

Input data in yellow cells.Calculated data in red cells.

0 10 20 30 40 50 60 70 80 90 1000

500100015002000250030003500400045005000

Profile

Performance rate [%]O

pear

iton

time

[h/a

]

Quantity of flue gasProportion of oxygen in flue gas [%] 3.5

Lambda [-] 1.20.9718

Temperature of flue gas [°C] 150Ambient temperature [°C] 0

10.25369.7712

12.20784

Performance rate [%] Heat content of flue gas [MJ]0 #VALUE! #VALUE!10 #VALUE! #VALUE!20 #VALUE! #VALUE!30 #VALUE! #VALUE!40 #VALUE! #VALUE!

50 #VALUE! #VALUE!

60 #VALUE! #VALUE!70 #VALUE! #VALUE!

80 #VALUE! #VALUE!

90 #VALUE! #VALUE!

100 #VALUE! #VALUE!

Heat content of flue gas [GJ/a] #VALUE!Heat input [GJ/a] #VALUE!

Heat loss due to flue gas [%/a] #VALUE!

X-axis (1)

Input data in yellow cells.Calculated data in red cells.

Specific heat of flue gas [kJ/(m3∙°C)]

Stoichiometrical quantity of flue gas [m3/m3]Stoichiometrical quantity of air [m3/m3]

Specific flue gas flow [m3/m3]

Flue gas flow [m3]

0 10 20 30 40 50 60 70 80 90 1000

500100015002000250030003500400045005000

Profile

Performance rate [%]

Ope

arito

n tim

e [h

/a]

0 10 20 30 40 50 60 70 80 90 1000

1

1

Heat loss due to flue gas

Heat input [MJ]Heat content of flue gas [MJ]

Heat

[MJ]

Different application for waste heat recoveryWaste heat for absorption chillerOutlet temp. of hot water [°C] 115 Heat can be used for this application.Inlet temp. of hot water [°C] 100

Required temperature diff. of heat exchangers, °C 15Reference efficiency [%] 85

X-axis (1) X-axis (2) Y-axis (1) Y-axis (2) Gradient #VALUE!0 #VALUE! 150 00 #VALUE! 135 00 #VALUE! 100 100

0 #VALUE! 115.0 115.0#VALUE! #VALUE! 115 0 Recovered heat [GJ/a] ###0 #VALUE! 115 100 ###

Waste heat for heating system

Outlet temp. of water [°C] 80 Heat can be used for this application.

Inlet temp. of water [°C] 60

X-axis (1) X-axis (2) Y-axis (1) Y-axis (2)0 #VALUE! 60 60

0 #VALUE! 80 80

#VALUE! #VALUE! 0 60 Recovered heat [GJ/a] ####VALUE! #VALUE! 80 60 ###

Waste heat for DHW-systemOutlet temp. of water [°C] 55 Heat can be used for this application.

Inlet temp. of water [°C] 12

X-axis (1) X-axis (2) Y-axis (1) Y-axis (2)0 #VALUE! 12 120 #VALUE! 55 55

#VALUE! #VALUE! 0 12 Recovered heat [GJ/a] ####VALUE! #VALUE! 55 12 ###

ConclusionQ a.c. #VALUE! [GJ/a] #VALUE! #VALUE! [MDL/a]Q h.s. #VALUE! [GJ/a] #VALUE! #VALUE! [MDL/a]

Q dhw.s. #VALUE! [GJ/a] #VALUE! #VALUE! [MDL/a]

Reduction of fuel [m3/a]

Reduction of fuel [m3/a]

Reduction of fuel [m3/a]

Vgas at reference efficiency [m3/a] Cgas

Vgas at reference efficiency [m3/a] Cgas

Vgas at reference efficiency [m3/a] Cgas

Input data in yellow cells.Calculated data in red cells.

0 0.5 1 1.5 2 2.50

20

40

60

80

100

120

140

160Different application for the waste heat recovery

Flue gas

Pinch point

Q a.c. #VALUE! [GJ/a] Vgas at reference efficiency #VALUE! [m3/a] Cgas #VALUE! [MDL/a]

Q h.s. #VALUE! [GJ/a] Vgas at reference efficiency #VALUE! [m3/a] Cgas #VALUE! [MDL/a]

Q dhw.s. #VALUE! [GJ/a] Vgas at reference efficiency #VALUE! [m3/a] Cgas #VALUE! [MDL/a]

Recovered heat [GJ/a]

Flue

gas

tem

pera

ture

[°c]

Financial analysis (Method: Simple payback period)Operations and maintenance costMaintance cost [EUR/a] 100000 2097000 [MDL/a]Fuel cost [EUR/m3] 0.38 7.97 [MDL/m3]Fuel cost [EUR/a] #VALUE! #VALUE! [MDL/a]MDL exchange rate [1 EUR] 20.97 MDLProject cost estimate:Engineering design [EUR] 3,030 63539

MDLEquipment procurement [EUR] 60,000 1258200Equipment installation [EUR] 30,000 629100Equipment commissioning [EUR] 30,000 629100Project support [EUR] 0 0

Simple payback period [Year] #VALUE!

SensitivityProject cost [MDL] 2,579,939

Rate of increase [%] 25Increased project cost [MDL] 3,224,924

Range of fuel cost [%]-10 -5 0 15 25

7.172 7.570 7.969 9.164 9.961

Fuel cost [MDL/m3] Simple payback period [Year]#VALUE! 0 #VALUE! #VALUE!#VALUE! 0 #VALUE! #VALUE!#VALUE! 0 #VALUE! #VALUE!#VALUE! 0 #VALUE! #VALUE!#VALUE! 0 #VALUE! #VALUE!

X-axis (1) X-axis (2) Y-axis (1) Y-axis (2)2,579,939 2,579,939 0 #VALUE!

Input data in yellow cells.

Fuel cost [MDL/m3]

0 500000 1000000 1500000 2000000 2500000 3000000 35000000

0.2

0.4

0.6

0.8

1Financial analysis

7.172

7.570

7.969

9.164

9.961

BaseProject cost [MDL]

Payb

ack

perio

d [Y

ear]

Fuel cost [MDL/m3]

Calculated data in red cells.

Used formulas:

Q – quantity of steam generated per secundum [kg/sec]

η – boiler efficiency [-]

λ – Excess air [-]

5.

Vfg,a – Actual flue gas flow [m3]

1.   

q – quantity of fuel used [m3]

hg – enthalpy of saturated steam [kJ/kg]

hf – enthalpy of feed water [kJ/kg]

LHV – Lower heating value [kJ/kg, kJ/m3]

top – operation time [sec]

2.    

L0 - Theoretical air required for complete combustion [m3/m3]

LHV - Lower heating value [MJ/m3]

3.    

V0 - Stoichiometrical quantity of flue gas [m3/m3]

LHV - Lower heating value [MJ/m3]

4.    

Vfg - Specific flue gas flow [m3/m3]

V0 - Stoichiometrical quantity of flue gas [m3/m3]

L0 - Theoretical air required for complete combustion [m3/m3]

Qfg - Heat content of flue gas [MJ]

tfg – Temperature of flue gas [°C]

ta - Ambient temperature [°C]

cp - Specific heat of flue gas [kJ/(m3 °C)]∙

6.

7.

8.

λ – Lambda [-] = (1+(EA/100)), where EA means excess air in [%]

9.

SPP – Simple payback period [Year]YB – Yearly benefits [MDL/a]

YC – Yearly costs [MDL/a]

PC - Project cost [MDL]

LHV - Lower heating value [MJ/m3 or MJ/kg]ci – Proportion of the i. component in the fuel [m3/m3 fuel or kg/kg fuel]

LHVi - Lower heating value of components[MJ/m3 or MJ/kg]

Qin – Heat input [MJ]

LHV - Lower heating value [MJ/m3 or MJ/kg]FC – Fuel consumption [m3 or kg]

O2 – Measured oxygen cocentration in flue gas [%]

Vfg,a – Actual flue gas flow [m3]Vfg - Specific flue gas flow [m3/m3]FC – Fuel consumption [m3 or kg]

10.

X Steam TablesExcel macros, IF-97 Steam tables. The excel scripts are stored inside this workbook. A complete list of functions for use is available on the "Calling functions" worksheetBy: Magnus Holmgren The steam tables are free and provided as is. We take no responsibilities for any errors in the code or damage thereby.

OBS: This workbook uses macros. Set security options in Tools:Macro:Security… to enable macros.

Saturation properties given temperature Saturation properties given pressureTemperature 110.00 °C Pressure 12.000 bar aSaturation pressure #VALUE! bar a Saturation temperature #VALUE! °CLiquid LiquidEnthalpy #VALUE! kJ/kg Enthalpy #VALUE! kJ/kgDensity #VALUE! kg/m3 Density #VALUE! kg/m3Entropy #VALUE! kJ/kgK Entropy #VALUE! kJ/kgKVapour VapourVapour enthalpy #VALUE! kJ/kg Vapour enthalpy #VALUE! kJ/kgVapour density #VALUE! kg/m3 Vapour density #VALUE! kg/m3Vapour Entropy #VALUE! kJ/kgK vapour Entropy #VALUE! kJ/kgKEvaporation energy #VALUE! kJ/kg Evaporation energy #VALUE! kJ/kg

Properties given pressure and temperature Properties given pressure and enthalpyPressure 1.00 bar a Pressure 12.57 bar aTemperature 100.00 °C Enthalpy 2788.00 kJ/kgEnthalpy #VALUE! kJ/kg Temperature #VALUE! °CDensity #VALUE! kg/m3 Density #VALUE! kg/m3Entropy #VALUE! kJ/kgK Entropy #VALUE! kJ/kgKVapour fraction #VALUE! % Vapour fraction #VALUE! %IF97 Region #VALUE! IF97 Region #VALUE!Phase #VALUE! Phase #VALUE!Isobaric heat capacity #VALUE! kJ/kg Isobaric heat capacity #VALUE! kJ/kgSpeed of sound #VALUE! m/s Speed of sound #VALUE! m/s

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The excel scripts are stored inside this workbook. A complete list of functions for use is available on the "Calling functions" worksheetThe steam tables are free and provided as is. We take no responsibilities for any errors in the code or damage thereby.OBS: This workbook uses macros. Set security options in Tools:Macro:Security… to enable macros.

X Steam Tables v2.6Steam tables by Magnus Holmgren according to IAPWS IF-97 The excel scripts are stored inside this workbook. (No extra files are needed. Start from a copy of this workbook. This page can be removed)For error-reporting, feedback, other units etc. contact:The steam tables are free and provided as is. We take no responsibilities for any errors in the code or damage thereby.OBS: This workbook uses macros. Set security options in Tools:Macro:Security… to enable macros.

Temperature Tsat_p 1 bar #VALUE! °C Saturation temperature T_ph 1 bar 100 kJ/kg #VALUE! °C Temperture as a function of pressure and enthalpy T_ps 1 bar 1 kJ/(kg K) #VALUE! °C Temperture as a function of pressure and entropy T_hs 100 kJ/kg 0.2 kJ/(kg K) #VALUE! °C Temperture as a function of enthalpy and entropyPressure psat_T 100 °C #VALUE! bar Saturation pressure p_hs 84 kJ/kg 0.3 kJ/(kg K) #VALUE! bar Pressure as a function of h and s. p_hrho ### kJ/kg 5 kg/m3 #VALUE! bar Pressure as a function of h and rho (density). Very unaccurate for solid water region since it's almost incompressible!Enthalpy hV_p 1 bar #VALUE! kJ/kg Saturated vapour enthalpy hL_p 1 bar #VALUE! kJ/kg Saturated liquid enthalpy hV_T 100 °C #VALUE! kJ/kg Saturated vapour enthalpy hL_T 100 °C #VALUE! kJ/kg Saturated liquid enthalpy h_pT 1 bar 20 °C #VALUE! kJ/kg Entalpy as a function of pressure and temperature. h_ps 1 bar 1 kJ/(kg K) #VALUE! kJ/kg Entalpy as a function of pressure and entropy. h_px 1 bar 0.5 #VALUE! kJ/kg Entalpy as a function of pressure and vapour fraction h_Tx 100 °C 0.5 #VALUE! kJ/kg Entalpy as a function of temperature and vapour fraction h_prho 1 bar 2 kg/m3 #VALUE! kJ/kg Entalpy as a function of pressure and density. Observe for low temperatures (liquid) this equation has 2 solutions. (Not valid!!)Specific volume vV_p 1 bar #VALUE! m3/kg Saturated vapour volume vL_p 1 bar #VALUE! m3/kg Saturated liquid volume vV_T 100 °C #VALUE! m3/kg Saturated vapour volume vL_T 100 °C #VALUE! m3/kg Saturated liquid volume v_pT 1 bar 100 °C #VALUE! m3/kg Specific volume as a function of pressure and temperature. v_ph 1 bar ### kJ/kg #VALUE! m3/kg Specific volume as a function of pressure and enthalpy v_ps 1 bar 5 kJ/(kg K) #VALUE! m3/kg Specific volume as a function of pressure and entropy.Density rhoV_p 1 bar #VALUE! kg/m3 Saturated vapour density rhoL_p 1 bar #VALUE! kg/m3 Saturated liquid density rhoV_T 100 °C #VALUE! kg/m3 Saturated vapour density rhoL_T 100 °C #VALUE! kg/m3 Saturated liquid density rho_pT 1 bar 100 °C #VALUE! kg/m3 Density as a function of pressure and temperature. rho_ph 1 bar ### kJ/kg #VALUE! kg/m3 Density as a function of pressure and enthalpy rho_ps 1 bar 1 kJ/(kg K) #VALUE! kg/m3 Density as a function of pressure and entropy.Specific entropy sV_p 0.01 bar #VALUE! kJ/(kg K) Saturated vapour entropy sL_p 0.01 bar #VALUE! kJ/(kg K) Saturated liquid entropy sV_T 0 °C #VALUE! kJ/(kg K) Saturated vapour entropy sL_T 100 °C #VALUE! kJ/(kg K) Saturated liquid entropy s_pT 1 bar 20 °C #VALUE! kJ/(kg K) Specific entropy as a function of pressure and temperature (Returns saturated vapour entalpy if mixture.) s_ph 1 bar ### kJ/kg #VALUE! kJ/(kg K) Specific entropy as a function of pressure and enthalpySpecific internal energy uV_p 1 bar #VALUE! kJ/kg Saturated vapour internal energy uL_p 1 bar #VALUE! kJ/kg Saturated liquid internal energy uV_T 100 °C #VALUE! kJ/kg Saturated vapour internal energy

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uL_T 100 °C #VALUE! kJ/kg Saturated liquid internal energy u_pT 1 bar 100 °C #VALUE! kJ/kg Specific internal energy as a function of pressure and temperature. u_ph 1 bar ### kJ/kg #VALUE! kJ/kg Specific internal energy as a function of pressure and enthalpy u_ps 1 bar 1 kJ/(kg K) #VALUE! kJ/kg Specific internal energy as a function of pressure and entropy.Specific isobaric heat capacity CpV_p 1 bar #VALUE! kJ/(kg°C) Saturated vapour heat capacity CpL_p 1 bar #VALUE! kJ/(kg°C) Saturated liquid heat capacity CpV_T 100 °C #VALUE! kJ/(kg°C) Saturated vapour heat capacity CpL_T 100 °C #VALUE! kJ/(kg°C) Saturated liquid heat capacity Cp_pT 1 bar 100 °C #VALUE! kJ/(kg°C) Specific isobaric heat capacity as a function of pressure and temperature. Cp_ph 1 bar 200 kJ/kg #VALUE! kJ/(kg°C) Specific isobaric heat capacity as a function of pressure and enthalpy Cp_ps 1 bar 1 kJ/(kg K) #VALUE! kJ/(kg°C) Specific isobaric heat capacity as a function of pressure and entropy.Specific isochoric heat capacity CvV_p 1 bar #VALUE! kJ/(kg°C) Saturated vapour isochoric heat capacity CvL_p 1 bar #VALUE! kJ/(kg°C) Saturated liquid isochoric heat capacity CvV_T 100 °C #VALUE! kJ/(kg°C) Saturated vapour isochoric heat capacity CvL_T 100 °C #VALUE! kJ/(kg°C) Saturated liquid isochoric heat capacity Cv_pT 1 bar 100 °C #VALUE! kJ/(kg°C) Specific isochoric heat capacity as a function of pressure and temperature. Cv_ph 1 bar 200 kJ/kg #VALUE! kJ/(kg°C) Specific isochoric heat capacity as a function of pressure and enthalpy Cv_ps 1 bar 1 kJ/(kg K) #VALUE! kJ/(kg°C) Specific isochoric heat capacity as a function of pressure and entropy.Speed of sound wV_p 1 bar #VALUE! m/s Saturated vapour speed of sound wL_p 1 bar #VALUE! m/s Saturated liquid speed of sound wV_T 100 °C #VALUE! m/s Saturated vapour speed of sound wL_T 100 °C #VALUE! m/s Saturated liquid speed of sound w_pT 1 bar 100 °C #VALUE! m/s Speed of sound as a function of pressure and temperature. w_ph 1 bar 200 kJ/kg #VALUE! m/s Speed of sound as a function of pressure and enthalpy w_ps 1 bar 1 kJ/(kg K) #VALUE! m/s Speed of sound as a function of pressure and entropy.Dynamic ViscosityViscosity is not part of IAPWS Steam IF97. Equations from "Revised Release on the IAPWS Formulation 1985 for the Viscosity of Ordinary Water Substance", 2003 are used.Viscosity in the mixed region (4) is interpolated according to the density. This is not true since it will be two fases. my_pT 1 bar 100 °C #VALUE! Pa s Viscosity as a function of pressure and temperature. my_ph 1 bar 100 kJ/kg #VALUE! Pa s Viscosity as a function of pressure and enthalpy my_ps 1 bar 1 kJ/(kg K) #VALUE! Pa s Viscosity as a function of pressure and entropy.

PrandtlCalcualted as Cp*my/tc pr_pT 1 bar 200 °C #VALUE! - pr_ph 1 bar ### kJ/kg #VALUE! -Thermal ConductivityRevised release on the IAPS Formulation 1985 for the Thermal Conductivity of ordinary water substance (IAPWS 1998) tcL_p 100 bar #VALUE! W/(m K) Saturated vapour thermal conductivity tcV_p 1 bar #VALUE! W/(m K) Saturated liquid thermal conductivity tcL_T 100 °C #VALUE! W/(m K) Saturated vapour thermal conductivity tcV_T 100 °C #VALUE! W/(m K) Saturated liquid thermal conductivity tc_pT 100 bar 350 °C #VALUE! W/(m K) Thermal conductivity as a function of pressure and temperature. tc_ph 1 bar 350 kJ/(kg K) #VALUE! W/(m K) Thermal conductivity as a function of pressure and enthalpy tc_hs 100 kJ/(kg K) 0.34 kJ/(kg K) #VALUE! W/(m K) Thermal conductivity as a function of enthalpy and entropySurface TensionIAPWS Release on Surface Tension of Ordinary Water Substance, September 1994 st_T 100 °C #VALUE! N/m Surface tension for two phase water/steam as a function of T st_p 1 bar #VALUE! N/m Surface tension for two phase water/steam as a function of TVapour fraction x_ph 1 bar ### kJ/kg #VALUE! Vapour fraction as a function of pressure and enthalpy

x_ps 1 bar 4 kJ/(kg K) #VALUE! Vapour fraction as a function of pressure and entropy.Vapour Volume FractionObserve that vapour volume fraction is very sensitive. Vapour volume is about 1000 times greater than liquid volume and therfore vapour volume fractiongets close to the accurancy of steam IF-97 vx_ph 1 bar 418 kJ/kg #VALUE! Vapour volume fraction as a function of pressure and enthalpy vx_ps 1 bar 4 kJ/(kg K) #VALUE! Vapour volume fraction as a function of pressure and entropy.

Version historyNews in V2.6* Error in valid region for function tc_ptrho* Error in function h3_pt for temperatures near the saturation point.

News in V2.5* DLL distrubution for use in other applications* Freebasic translation

* Fixed small error in Cv Region 5 p>1000barNews in V2.4a* ToSIUnit for h_ps region 4. (No effect in SI unit version).News in V2.4* Functions by p,rho inplemented in matlab also.* Many missing ; in matlab causing printouts detected.* OpenOffice version introduced. (Fixed calculation differences in open office and excel)* Matlab error giving varaible undefined in some backwards solutions fixed.News in V2.3* Option Explicit, gives more efficient calculations.* Extensive testing* my_ph not defined in region 4.* Problems at region border for h4V_p to adress solver problems at the exact border.* Problem at fast border check in region_ph fixed.News in V2.2* Extensive testing* Fixed error in Cp_ph

* Function p_hrho added. (Very good for calcualting pressure when heating a volume with water/steam mixture.)* Fixed error in T_hs return no value for vet region bellow the water saturation line.* Prandtl number added

News in V2.1* Calling function h_prho* Fixed problem with Cv reporting NaN in region 5.* Equivivalent to the Matlab version. (Downloadable from www.x-eng.com)News in V2* Calling functions of h and s added.* Thermal conductivity, Surface tension added

* Calling functions h_px and h_tx added.* Cp, Cv and w undefined in the mixed region. (Before interpolation with the vapor fraction was used.)* A work sheet "Properties" for simple lookups added.

The excel scripts are stored inside this workbook. (No extra files are needed. Start from a copy of this workbook. This page can be removed)

Saturation temperatureTemperture as a function of pressure and enthalpyTemperture as a function of pressure and entropyTemperture as a function of enthalpy and entropy

Pressure as a function of h and s. Pressure as a function of h and rho (density). Very unaccurate for solid water region since it's almost incompressible!

Saturated vapour enthalpySaturated liquid enthalpySaturated vapour enthalpySaturated liquid enthalpyEntalpy as a function of pressure and temperature.Entalpy as a function of pressure and entropy.Entalpy as a function of pressure and vapour fractionEntalpy as a function of temperature and vapour fractionEntalpy as a function of pressure and density. Observe for low temperatures (liquid) this equation has 2 solutions. (Not valid!!)

Saturated vapour volumeSaturated liquid volumeSaturated vapour volumeSaturated liquid volumeSpecific volume as a function of pressure and temperature.Specific volume as a function of pressure and enthalpySpecific volume as a function of pressure and entropy.

Saturated vapour densitySaturated liquid densitySaturated vapour densitySaturated liquid densityDensity as a function of pressure and temperature.Density as a function of pressure and enthalpyDensity as a function of pressure and entropy.

Saturated vapour entropySaturated liquid entropySaturated vapour entropySaturated liquid entropySpecific entropy as a function of pressure and temperature (Returns saturated vapour entalpy if mixture.)Specific entropy as a function of pressure and enthalpy

Saturated vapour internal energySaturated liquid internal energySaturated vapour internal energy

Saturated liquid internal energySpecific internal energy as a function of pressure and temperature.Specific internal energy as a function of pressure and enthalpySpecific internal energy as a function of pressure and entropy.

Saturated vapour heat capacity Saturated liquid heat capacity Saturated vapour heat capacity Saturated liquid heat capacity Specific isobaric heat capacity as a function of pressure and temperature.Specific isobaric heat capacity as a function of pressure and enthalpySpecific isobaric heat capacity as a function of pressure and entropy.

Saturated vapour isochoric heat capacitySaturated liquid isochoric heat capacitySaturated vapour isochoric heat capacitySaturated liquid isochoric heat capacitySpecific isochoric heat capacity as a function of pressure and temperature.Specific isochoric heat capacity as a function of pressure and enthalpySpecific isochoric heat capacity as a function of pressure and entropy.

Saturated vapour speed of soundSaturated liquid speed of soundSaturated vapour speed of soundSaturated liquid speed of soundSpeed of sound as a function of pressure and temperature.Speed of sound as a function of pressure and enthalpySpeed of sound as a function of pressure and entropy.

Viscosity is not part of IAPWS Steam IF97. Equations from "Revised Release on the IAPWS Formulation 1985 for the Viscosity of Ordinary Water Substance", 2003 are used.

Viscosity as a function of pressure and temperature.Viscosity as a function of pressure and enthalpyViscosity as a function of pressure and entropy.

Saturated vapour thermal conductivitySaturated liquid thermal conductivitySaturated vapour thermal conductivitySaturated liquid thermal conductivityThermal conductivity as a function of pressure and temperature.Thermal conductivity as a function of pressure and enthalpyThermal conductivity as a function of enthalpy and entropy

Surface tension for two phase water/steam as a function of TSurface tension for two phase water/steam as a function of T

Vapour fraction as a function of pressure and enthalpy

Vapour fraction as a function of pressure and entropy.

Observe that vapour volume fraction is very sensitive. Vapour volume is about 1000 times greater than liquid volume and therfore vapour volume fraction

Vapour volume fraction as a function of pressure and enthalpyVapour volume fraction as a function of pressure and entropy.

Entalpy as a function of pressure and density. Observe for low temperatures (liquid) this equation has 2 solutions. (Not valid!!)