[ranjith prakash]

I am doing a project on cfd analysis of ejector in a ejector-refrigeration system. There are two inlet and one outlet. the fluids are refrigerant vapour. from the papers it is mentioned that the density, thermal conductivity and other properties are polynomial variations of temperature and udf needs to be added. how to give udf for this?

[movaffagh]

Originally Posted by ranjith prakash

I am doing a project on cfd analysis of ejector in a ejector-refrigeration system. There are two inlet and one outlet. the fluids are refrigerant vapour. from the papers it is mentioned that the density, thermal conductivity and other properties are polynomial variations of temperature and udf needs to be added. how to give udf for this?

hi body,
you can set your polynomial's coefficints in material section.

[ranjith prakash]

Originally Posted by movaffagh

hi body,
you can set your polynomial's coefficints in material section.

Thanks for the reply but I couldn't see the variation equation in those papers. Actually from Refprop software we can take the properties According to the pressure and temperature but without udf how ansys is able to know the variation of fluid properties with temperature. For me the boundary conditions are pressures.

[movaffagh]

Originally Posted by ranjith prakash

Thanks for the reply but I couldn't see the variation equation in those papers. Actually from Refprop software we can take the properties According to the pressure and temperature but without udf how ansys is able to know the variation of fluid properties with temperature. For me the boundary conditions are pressures.

the bc is not important. when you want to give property of material in ansys fluent, you have more option like: constant,linear,polynomial,pieswise and ...
and you can give your property depend on temp.