WOLFRAM SYSTEM MODELER

s_pTX_der

Return specific entropy of moist air as a function of pressure p, temperature T and composition X (only valid for phi<1)

Wolfram Language

In[1]:=
SystemModel["Modelica.Media.Air.MoistAir.s_pTX_der"]
Out[1]:=

Information

This information is part of the Modelica Standard Library maintained by the Modelica Association.

Specific entropy of moist air is computed from pressure, temperature and composition with X[1] as the total water mass fraction.

Syntax

ds = s_pTX_der(p, T, X, dp, dT, dX)

Inputs (6)

p

Type: Pressure (Pa)

Description: Pressure
T

Type: Temperature (K)

Description: Temperature
X

Type: MassFraction[:]

Description: Mass fractions of moist air
dp

Type: Real (Pa/s)

Description: Derivative of pressure
dT

Type: Real (K/s)

Description: Derivative of temperature
dX

Type: Real[nX] (1/s)

Description: Derivative of mass fractions

Outputs (1)

ds

Type: Real (J/(kg⋅K⋅s))

Description: Specific entropy at p, T, X

Revisions

2012-01-12 Stefan Wischhusen: Initial Release.

2019-05-14 Stefan Wischhusen: Corrected calculation.

2019-09-10 Stefan Wischhusen: Corrected pressure influence (p < p_ref).