Heat transfer coefficient
Hello! I'm student and have some problem... Can somebody help me: were I can find some information how calculate heat transfer coefficient from cfd data: (1) when I use wall function and boundary gradients (2) may be another methods? My problem is heat sink for cooling semiconductor elements with force convection.

Re: Heat transfer coefficient
Dear Eugene,
Flotherm is the market leading CFD thermal modelling software used in the electronics industry worldwide. Please refer to http://www.flomerics.com for more information. 
Re: Heat transfer coefficient
The wallfunction formulae employ a local Stanton number St from which the local heat transfer coefficient (htc) can be determined from St*density*relative velocity*specific heat. The formula for St depends on the actual empirical correlation used. For an example see http://www.cham.co.uk/phoenics/d_pol...od/enc_tu8.htm ). Commericial codes usually make provision for the output of the htc, but if you are using a research code you will have to calculate it yourself.

Re: Heat transfer coefficient
Hello! Can you advice me how to calculate Heat transfer coefficient from Phoenics. I have STAN and SKIN for wall function 'loglaw' and KEEP turbulence model. My case is air flow in channel. For boundary cell I have: (1) Alfa1=Ro(air)*U1*Cp(air)*STAN were U1fist point in air. (2) Nu(real)=STAN*(TwT1)/(TwT(overal))*U1/U(overall)*Re*Pr were U(overall)=Integral(Udx)/Integral(dx) T(overall)=Integral(U*T*dx)/Integral(U*dx) (3) Alfa(real)/Alfa(1)=(TwT1)/(TwT(overall))
But this algoritm is not working in conner area. And STAN have have strange profile >1/Alfa1... Why? 
Re: Heat transfer coefficient
STORE(HTCO) should elicit storage and printout of the heat transfer coefficient.
I suspect that the printed corner Stanton number refers to one of the corner faces (whichever was calculated last) and is not a weighted average of the two corner faces. I don't understand what is meant by: "And STAN have have strange profile >1/Alfa1...". Provide a more detailed and precise explanation. I suggest that you submit PHOENICS questions to the PHOENICS Discussion Group rather than the Main one. 
All times are GMT 4. The time now is 21:56. 