Learning Forum

[mmoataz]

I am simulating a heat exchanger that has an input heating power of 30kW on Fluent using a pressure-based solver. To achieve this, I defined a mass-flow-rate inlet boundary condition at the hot air side with the correct inlet temperature and specific heat. However, the enthalpy was not calculated correctly resulting in a less input power of 26kW. The reason for that is that for pressure-based solvers enthalpies are calculated based on reference temperature of 298.15K as shown in the screen shot below taken from Fluent documentation.nWhen I tried the density-based solver, the inlet enthalpy and input power were calculated correctly but the solution doesn't converge in this case.nMy question is:nCan the reference temperature be changed for the pressure-based solver to 0K instead? Or can I add a value for enthalpy at 298.15 instead of 0kJ/kg?nI have already tried to do so from the Reference values panel but it had no effect. nPlease advise.nThank youn

[DrAmine]

It is hard coded. You might though define Cp via UDF and here you provide Tref. Other alternative us to use species model with one component and define standard state enthalpy as required. Other alternative using UDRGM or RGP.n

[mmoataz]

Thank you DrAmine, I've used species model with one component as you suggested and now I get the correct numbers.n

[DrAmine]

Super.n