Modeling heat loss or gain in a recirculation loop

You can model heat loss or gain in the fluid between the flow extract and return openings. This allows you to model a closed circuit heating or cooling system.

You specify how the heat loss or gain is defined by specifying one of the following:

• The temperature difference between the fluid at the extract and return openings, . If you specify a positive value, heat is added to the fluid, and if you specify a negative value, heat is removed from the fluid. The flow solvers compute the temperature at the return opening as follows:T_{return}=T_{extract}+ \Delta Twhere Textract is the fluid temperature at the extract region.

• The heat gain or loss to the fluid between the extract and return openings, Q. If you specify a positive value, heat is added to the fluid, and if you specify a negative value, heat is removed. The flow solvers compute the temperature at the return opening as follows:T_{return}=T_{extract}+\frac{Q}{\dot{m}\times C_p}where: is the mass flow rate.Cp is the specific heat of the fluid material.

• A heat transfer coefficient, h, the convecting area, Aw, and the environment temperature Tenv. The software uses these values to compute the heat convected either to or from the fluid. The serial flow solver computes the temperature at the return opening as follows:T_{return}=T_{extract}+\frac{hA_w}{\dot{m} \times C_p}(T_{env}-T_{extract})The parallel flow solver computes the temperature at the return opening as:T_{return}=T_{env}-(T_{env}-T_{extract})e^{-\frac{hA_w}{\dot{m}\times C_p}}

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Modeling heat loss or gain in a recirculation loop, Simcenter 3D 2021.1 Series

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