Oil quadratic viscosity¶
With this model the oil viscosity has a quadratic dependence with respect to the pressure and temperature. Two reference values are required for both pressure and temperature, plus corresponding coefficients.
See an example below:
EOS OIL DENSITY CONSTANT 734.29d0 !kg/m3 ENTHALPY LINEAR_TEMP 1.d3 !c oil [J/kg/°C] VISCOSITY QUADRATIC REFERENCE_VALUE 2.94d-3 PRES_REF_VALUES 1.d5 0.0 TEMP_REF_VALUES 10.0 0.0 PRES_COEFFICIENTS 0.0d0 0.0d0 TEMP_COEFFICIENTS -0.01522d-3 0.0d0 END END
The mathematical expression of the model is as follows:
Setting to zero the quadratic coefficients the quadratic model simplifies to a linear model. Units cannot be specified, therefore values must be entered in the units prescribed above.