I am modeling the heat transfer between a laptop and its environment in a closed room. The temperature diagramm shows me a reversed temperature : the laptop is colder than the environment! I tried both negative and positive values for the the heat generation rate but it seems not to resolve the problem. I would really appreciate any help or advise. Thanks.

the only advice is TRIPLE check that you set the problem right in fluent. do your heat balance correctly and try to change the values to see if there's different in results especially the sign. lastly, remember that fluent works in Kelvin(K) and all Tspec has to be in K, if you're using SI. I'm not metric fun so I can't comment on that. good luck