q0 = h Text – T

For a thorough introduction about how to calculate heat transfer coefficients, see Incropera and DeWitt in Ref. 1.

•If Total heat flux is selected, enter the total heat flux qtot (SI unit: W) for the total heat flux across the boundaries where the Heat Flux node is active.

Inflow Heat Flux

Use the Inflow Heat Flux node to model inflow of heat through a virtual domain with a heat source. The temperature at the outer boundary of the virtual domain is known. The Inward Heat Flux boundary condition estimates the heat flux through the system boundary

A positive heat flux adds heat to the domain. The Inflow Heat Flux feature is applicable to inlet boundaries.

The second integral in Equation 13-2 is neglected if the Inflow Heat Flux feature is applied to the boundary of a solid domain.

B O U N D A R Y S E L E C T I O N

From the Selection list, choose the boundaries to add the heat flux contribution.

I N F L O W H E A T F L U X

Enter a value or expression for each of the following properties:

•General inward heat flux q0 (SI unit: W/m2) to add to the total flux across the selected boundaries. The default value is 0.

•External temperature Text (SI unit: K). The default value is 273.15 K.

•External absolute pressure pext (SI unit: Pa). The default value is 1 atm.

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