  # List of TriHumidAir Worksheet Functions

• The tables below give a complete list of TriHumidAir worksheet functions.
• The rows that are shaded blue describe input parameters to the functions listed below.
• All functions use the SI system of units.
• The term 'Mixing Ratio' is used instead of 'Humidity Ratio'.

General

Moist Air Properties from Pressure, Temperature and Relative Humidity

Moist Air Properties from Pressure, Temperature and Mixing Ratio

Heating and Cooling of a Moist Air Flow

General
 General: Moist Air Properties from Pressure and Temperature Property Formula Unit Pressure P Pa Dry Bulb Temperature T °C Relative Humidity RH Water Vapour at Saturation Pressure (H2O Only) Pws0 = f(T) [Pa] WSatP0(t) Pa Water Saturation Pressure (In Air at Given Pressure) Pws = f(P, T) [Pa] WSatP(P,t) Pa Saturation Mixing Ratio Ws = f(P, T) [kg/kg] SatMixRatio(P,t) kg/kg General: Moist Air Mass Flows Property Formula Unit Mass Flow of Moist Air Mixture (Air + Water) M kg/s Mixing Ratio W kg/kg Mass Flow of Air Ma = f(M, W) [kg/s] MassFlowAir_M(m,W) kg/s Mass Flow of Water Mw = f(M, W) [kg/s] MassFlowWater_M(m,W) kg/s Mass Flow of Air Ma kg/s Mixing Ratio W kg/kg Mass Flow of Moist Air Mixture (Air + Water) M = f(Ma, W) [kg/s] MassFlowMix_Ma(Ma,W) kg/s Mass Flow of Water Mw = f(Ma, W) [kg/s] MassFlowWater_Ma(Ma,W) kg/s General: Moist Air Temperature from Enthalpy Property Formula Unit Pressure P Pa Mixing Ratio W kg/kg Enthalpy of Moist Air per Unit of Mass of Dry Air H kJ/kg dry air Moist Air Temperature from Enthalpy T = f(P, W, H) [°C] Temp_H(P,W,H) °C General: Specific Enthalpy of Water (Any Phase) in Equilibrium With Saturated Air at 101,325 Pa Property Formula Unit Pressure P Pa Dry Bulb Temperature T °C Calculate for Ice CalcIce Specific enthalpy of water (any phase) in equilibrium with saturated air at 101,325 Pa Formulas derived from ASHARE Fundamentals Book, Chapter 6, Table 1. This function should be expanded to cover pressures other than 101,325 Pa. Therefore, the pressure is used as an input parameter if CalcIce is True, Hw is calculated for ice at triple point (saturation) (T=0.01°C) H = f (P, T) [kJ/kg] Hw_P_T(P,T,Optional:CalcIce) kJ/kg General: Specific Enthalpy of Saturated Steam Property Formula Unit Pressure P Pa Specific enthalpy of saturated steam for a given pressure H = f(P) [kJ/kg] Hg_P(P) kJ/kg Temperature T °C Specific enthalpy of saturated steam for a given temperature H = f(T) [kJ/kg] Hg_T(T) kJ/kg

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Moist Air Properties from Pressure, Temperature and Relative Humidity
 Property Formula Unit Pressure P Pa Dry Bulb Temperature T °C Relative Humidity RH Partial Pressure of Water Vapour Pw = f(P, T, RH) [Pa] WPartP_RH(P,t,RH) Pa Degree of Saturation µ = f(P, T, RH) [-] DegreeOfSat_RH(P,t,RH) - Density of Moist Air Rho = f(P, T, RH) [kg/m³] DensMoistAir_RH(P,t,RH) kg/m³ Volume of Moist Air Mixture (per Unit Mass of Dry Air) v = f(P, T, RH) [m³/kg] VolMoistMix_RH(P,t,RH) m³/kg dry air Enthalpy of Moist Air per Unit of Mass of Dry Air h = f(P, T, RH) [kJ/kg dry air] EnthalpyMoistAir_RH(P,t,RH) kJ/kg dry air Enthalpy of Moist Air per Unit of Mass of Mixture hm = f(P, T, RH) [kJ/kg mix] EnthalpyMix_RH(P,t,RH) kJ/kg mix Dewpoint of Moist Air Td = f(P, T, RH) [°C] DewPoint_RH(P,t,RH) °C Wet Bulb Temperature of Moist Air Twb = f(P, T, RH) [°C] WetBulb_RH(P,t,RH) °C Mixing Ratio W = f(P, T, RH) [kg/kg] MixRatio_RH(P,t,RH) kg/kg Relative Humidity RH

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Moist Air Properties from Pressure, Temperature and Mixing Ratio
 Property Formula Unit Pressure P Pa Dry Bulb Temperature T °C Mixing Ratio W kg/kg Partial Pressure of Water Vapour Pw = f(P, T, W) [Pa] WPartP_W(P,t,W) Pa Degree of Saturation µ = f(P, T, W) [-] DegreeOfSat_RH(P,t,W) - Density of Moist Air Rho = f(P, T, W) [kg/m³] DensMoistAir_W(P,t,W) kg/m³ Volume of Moist Air Mixture (per Unit Mass of Dry Air) v = f(P, T, W) [m³/kg] VolMoistMix_W(P,t,W) m³/kg dry air Enthalpy of Moist Air per Unit of Mass of Dry Air h = f(P, T, W) [kJ/kg dry air] EnthalpyMoistAir_W(P,t,W) kJ/kg dry air Enthalpy of Moist Air per Unit of Mass of Mixture hm = f(P, T, W) [kJ/kg mix] =EnthalpyMix_W(P,t,W) kJ/kg mix Dewpoint of Moist Air Td = f(P, T, W) [°C] DewPoint_W(P,t,W) °C Wet Bulb Temperature of Moist Air Twb = f(P, T, W) [°C] WetBulb_W(P,t,W) °C Mixing Ratio W Relative Humidity RH = f(P, T, W) [-] RelHumidity_W(P,t,W)

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Moist Air Properties from Pressure, Temperature and Wet Bulb Temperature
 Property Formula Unit Pressure P Pa Dry Bulb Temperature T °C Wet Bulb Temperature Twb °C Duct Inside Wall Temperature Too °C Duct velocity V m/s Wet Bulb Diameter, default 0.007 m (7 mm) Dwb m Wet Bulb Emmittance [0 to 1], default 0.85 Ewb - Lewis Number [0.85 to 1], default 0.85 Le - Partial Pressure of Water Vapour Pw = f(P, T, Twb) [Pa] WPartP_Twb(P,t,Twb) Pa Degree of Saturation µ = f(P, T, Twb) [-] DegreeOfSat_Twb(P,T,Twb) - Density of Moist Air Rho = f(P, T, Twb) [kg/m³] DensMoistAir_Twb(P,t,Twb) kg/m³ Volume of Moist Air Mixture (per Unit Mass of Dry Air) v = f(P, T, Twb) [m³/kg] VolMoistMix_Twb(P,t,Twb) m³/kg dry air Enthalpy of Moist Air per Unit of Mass of Dry Air h = f(P, T, Twb) [kJ/kg dry air] EnthalpyMoistAir_Twb(P,t,Twb) kJ/kg dry air Enthalpy of Moist Air per Unit of Mass of Mixture hm = f(P, T, Twb) [kJ/kg mix] EnthalpyMix_Twb(P,t,Twb) kJ/kg mix Dewpoint of Moist Air Td = f(P, T, Twb) [°C] DewPoint_Twb(P,t,Twb) °C Wet Bulb Temperature Twb °C Mixing Ratio W = f(P, T, Twb) [kg/kg] MixRatio_Twb(P,T,Twb) kg/kg Mixing ratio from Twb calculated for mass and heat transfer W = f(P, T, Twb, Too, V, Dwb, Ewb, Le) [kg/kg] MixRatio_Twb1(P,T,Twb,Too,V, Dwb,Ewb,Le) kg/kg Relative Humidity RH = f(P, T, Twb) [-] RelHumidity_Twb(P,T,Twb)

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Heating and Cooling of a Moist Air Flow
 Property Formula Unit Pressure P Pa Mass Flow of Air Ma kg/s Dry Bulb Temperature at Inlet T1 °C Mixing Ratio at Inlet W1 kg/kg Heating or Cooling Power Between Inlet and Exit Q kW Temperature After Heating or Cooling Moist Air Flow T2 = f(P, Ma, T1, W1, Q) [°C] Temp2_Q(P,Ma,T1,W1,Q) °C Mixing Ratio After Heating or Cooling Moist Air Flow W2 = f(P, Ma, T1, W1, Q) [kg/kg] MixRatio2_Q(Ma,P,T1,W1,Q) kg/kg Condensate Water Flow Rate After Cooling Moist Air Flow 'Mc = f(P, Ma, T1, W1, Q) [kg/s] CondensateFlow_Q(Ma,P,T1, W1,Q) kg/s Pressure P Pa Mass Flow of Air Ma kg/s Dry Bulb Temperature at Inlet T1 °C Dry Bulb Temperature at Exit T2 °C Mixing Ratio at Inlet W1 kg/kg Required Power for Heating or Cooling Moist Air Flow Q = f(P, Ma, T1, T2, W1) [kW] Power_T2(P,Ma,T1,T2,W1) kW Mixing Ratio After Heating or Cooling Moist Air Flow T2 = f(P, Ma, T1, T2, W1) [kg/kg] MixRatio2_T2(P,Ma,T1,T2,W1) kg/kg Condensate Water Flow Rate After Cooling Moist Air Flow 'Mc = f(P, Ma, T1, T2, W1) [kg/s] CondensateFlow_T2(P,Ma,T1, T2,W1) kg/s

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Adiabatic Mixing of Two Streams of Moist Air
 Property Formula Unit Pressure P Pa Mass Flow of Dry Air - Inlet Stream 1 Ma1 kg/s Mass Flow of Dry Air - Inlet Stream 2 Ma2 kg/s Dry Bulb Temperature - Inlet Stream 1 T1 °C Dry Bulb Temperature - Inlet Stream 2 T2 °C Mixing Ratio - Inlet Stream 1 W1 kg/kg Mixing Ratio - Inlet Stream 2 W2 kg/kg Enthalpy of Mixed Airstream H3 = f(P, Ma1, Ma2, T1, T2, W1, W2) [°C] Enthalpy3_mix(P,Ma1,Ma2,T1,T2,W1,W2) kJ/kg dry air Temperature of Mixed Airstream T3 = f(P, Ma1, Ma2, T1, T2, W1, W2) [°C] Temp3_mix(P,Ma1,Ma2,T1,T2,W1,W2) °C Mixing Ratio of Mixed Airstream W3 = f(P, Ma1, Ma2, T1, T2, W1, W2) [kg/kg] MixRatio3_mix(P,Ma1,Ma2,T1,T2,W1,W2) kg/kg Condensate Water Flow Rate with Mixed Airstream Mw3 = f(P, Ma1, Ma2, T1, T2, W1, W2) [kg/s] CondensateFlow3_mix(P,Ma1,Ma2,T1,T2, W1,W2) kg/s

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Adiabatic Mixing of Moist Air with Injected Water or Steam
 Property Formula Unit Pressure P Pa Mass Flow of Air Ma kg/s Mass Flow of Injected Water Mw1 kg/s Dry Bulb Air Temperature at Inlet Ta1 °C Temperature of Injected Water Tw1 °C Mixing Ratio at Inlet W1 kg/kg Equivalent bypass factor (0<=B<=1) B=1-Mu, where Mu is Humidification efficiency For Steam injection specify B as: B = -1 (Steam Enthalpy based on pressure P) B = -2 (Steam Enthalpy based on temperature Mw1) B Factor that determines where Tdap lies between Twb1 and Tw2 (0<=C<=1) (for C=0 Tadp=Tw1; for C=1 Tadp=Tw2; C->1 for B->0) C Exit Air Temperature after injecting water into moist airflow Ta2 = f(P, Ma, Mw1, Ta1, Tw1, W1, B, C) [°C] AirTemp2_WI(P,Ma,Mw1, Ta1,Tw1,W1,B,C) °C Exit Water Temperature after injecting water into moist airflow Tw2 = f(P, Ma, Mw1, Ta1, Tw1, W1, B, C) [°C] WaterTemp2_WI(P,Ma,Mw1, Ta1,Tw1,W1,B,C) °C Apparatus Dewpoint Temperature (injecting water into moist airflow) Tadp = f(P, Ma, Mw1, Ta1, Tw1, W1, B, C) [°C] Tadp_WI(P,Ma,Mw1,Ta1,Tw1, W1,B,C) °C Exit Mixing Ratio after injecting water into moist airflow W2 = f(P, Ma, Mw1, Ta1, Tw1, W1, B, C) [kg/kg] MixRatio2_WI(P,Ma,Mw1,Ta1, Tw1,W1,B,C) kg/kg Exit Relative Humidity RH2 = (P,Ta2,W2) RelHumidity_W(P,Ta2,W2) Evaporated Injected Water Mwe = f(P, Ma, Mw1, Ta1, Tw1, W1, B, C) [kg/s] WaterEvap_WI(P,Ma,Mw1,Ta1, Tw1,W1,B,C) kg/s Exit Water Flow after injecting water into moist airflow Mw2 = f(P, Ma, Mw1, Ta1, Tw1, W1, B, C) [kg/s] WaterFlow2_WI(P,Ma,Mw1,Ta1, Tw1,W1,B,C) kg/s

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