...I´m using Floworks to simulate natural convectionheat transferon a rectangular finned surface. The heat sink is madefromaluminum, the fluid is air, i Know the initial temperature ofairand the initial temperature of the heat sink (same as theairtemperature). I also know the heat fluxon the lower base oftheheat sink.As indicated by Floworks help topics I check theboxconsidering gravitational effects an started thetransientsimulation.After the simulation I´m able to get theheat transfercoefficients on the heat sink. This is the point! HowFloworkscansolve a heat transfer problem without knowing the heattransfercoefficient?? I tried to do the same simulation onotherFeasoftware and some of them can not start the simulationwithout agiven heat transfer coefficient...anyone knows what´sgoingon?thanksfabioSolidworksFlow Simulation