D O M A I N S E L E C T I O N

From the Selection list, choose the domains to add pressure work. By default, the selection is the same as for the Heat Transfer in Fluids feature that it is attached to.

D Y N A M I C V I S C O S I T Y

Specify the Dynamic viscosity (SI unit: Pa·s). The default setting is to use the value of the viscosity from the material. Select User defined to define another value for the viscosity.

The program uses the dynamic viscosity together with the velocity expressions to compute the viscous stress tensor, .

Heat Source

The Heat Source describes heat generation within the domain. Express heating and cooling with positive and negative values, respectively. Add one or more nodes as required—all heat sources within a domain contribute to the total heat source. Specify the heat source as the heat per volume in the domain, as linear heat source, or as a total heat source (power).

D O M A I N S E L E C T I O N

From the Selection list, choose the domains to add the heat source.

H E A T S O U R C E

Click the General source, Linear source, or Total power button.

•If General source is selected, enter a value for the distributed heat source Q (SI unit: W/m3).

•If Total power is selected, enter the total power (total heat source) Ptot (SI unit: W).

•If Linear source (Q qs·T) is selected, enter the Production/absorption coefficient qs

(SI unit: W/(m3·K)).

The advantage of writing the source in this form is that it can be stabilized by the streamline diffusion. The theory covers qs that is independent of

the temperature, but some stability can be gained as long as qs is only

Tip

weakly dependent on the temperature.

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