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[vkr535]

test_1d_therm.txt

[Kai]

Hi, below is some old comments related to this problem.nA negative film coefficient (heat transfer coefficient) is usually considered non-physical since it would imply that if the bulk temperature is hotter than the surface temperature, heat would be removed rather than added to the system.nThat being said, however, a negative film coefficient can be defined by using the material property HF lookup table. With the SF family of commands, specify a value of -N, where N is the material ID of MP,HF. Then, one can define constant or temperature-dependent film coefficients with values in MP,HF (see also MPTEMP and MPDATA commands).nSince a negative value for film coefficient in the SF family of commands refers to the material ID of a lookup table in MP,HF, a user cannot specify negative film coefficients directly. Also, tabular loads cannot be used, either, as evaluated negative values are also assumed to be pointing to the MP,HF material ID number.n

[vkr535]

Hello Team,nThank you for the response. I checked giving negative values to HF in MP command and its working now and clean.