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

This function computes the residual helmholtz derivatives of the fundamental equation of Tillner-Roth and Baehr for R134a (1994) w.r.t. to reduced temperature (tau=T_crit/T) and reduced density (delta=rho/rho_crit). The function can be used for special properties depending just on the residual derivative parts.

f = fres_R134a(delta, tau)

delta	Type: Real Description: Reduced density (delta=d/dcrit)
tau	Type: Real Description: Reduced temperature (tau=Tcrit/T)

f	Type: HelmholtzDerivs Description: Helmholtz derivatives