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Heat flux density in 2D simulation

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Old   September 29, 2022, 19:55
Default Heat flux density in 2D simulation
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Bob
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I have done a 2D simulation of a rectangular cell. I set a fixed temperature at one wall. Now I want to determine the heat flux density of this wall. To do this, I measured the heat flux of that wall [in W]. How can I now determine the heat flux density [W/m^2]? Becaus in 2D I have only one dimension of the wall because the wall is an edge.


How can ANSYS determine the heat flow of a 2D "surface" at all? Doesn't it need a 3D surface for that?
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Old   September 29, 2022, 21:22
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FYI what you are calling heat flux density, everybody else calls heat flux. Heat flux has units of W/m^2 and not W.

Fluent gives you the heat flux on boundaries, it is readily available in a variable called wall heat flux. Just select it.

FVM is always a balance of fluxes going into and out of each computational cell, whether in 2D or 3D. You don't need to worry about how heat flux is obtained because it is a fundamental input to FVM. Actually, you should be more concerned with how Ansys gives you a heat in W because that does depend on an area (that you don't have)! You didn't ask how heat is calculated in a 2D simulation, but the answer is that Fluent takes the heat flux (in W/m^2) and multiplies it by the reference depth which you input in the reference values pane. You can actually get different values for heat rate in W by simply changing the value of the reference depth, but the heat flux will not change.
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Old   September 2, 2024, 08:39
Default 2D heat flux values are wrong, need help in refeence values
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I want to know what reference value im doing wrong cause total heat flux, is coming in 10^-12 terms, and stanton number is not showing up at all, my contours are looking good but these values are important for paper.
geometry is 2d. what should i do, tried many things, didn't work out.
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Old   September 6, 2024, 05:30
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You can make a mesh with one cell thick and you will get the area of ​​the wall
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