I simulated a pipe with bends with air as the medium. I specified an input velocity of 4.42 m/s and an output pressure of 0 Pa, with a diameter of 200 mm. After the simulation, the inlet pressure was about 4 - 5 Pa on average. Now I assume that this is the static pressure, as the dynamic pressure is already approx. 11.6 Pa. What exactly is the pressure given in the statistics?
Hi there, would it be possible to add the link to your project too, please?
Best regards,
Fillia
I would like to simulate that the resistance coefficient of the 2nd bend in an air duct behaves differently in a direct connection than that of the first. Since pressure loss calculations often simply multiply the resistance coefficient by 2 in such cases, but the coefficient must change due to the previous deflection, this assumption cannot be correct. I would like to prove this.
First I used the standard meshing method and set the highest possible fineness of 10. Unfortunately, this took a long time and the non-orthogonality was very high. In addition, the residuals did not converge. Then I chose the Hex-dominant method, also at the highest fineness. Here the meshing log shows that there are no non-orthogonalities of >70° anywhere. However, at the end it says that the maximum non-orthogonality is at values above 70°. But the residuals are now converging, except for one simulation. Nevertheless, I get comparatively low resistance coefficients when compared with the literature values. Also, I don’t know how Simscale calculates the pipe friction losses. Usually I would use Colebrook-White iteration and calculate the lambda value. I have set a roughness of 0.15 mm here. Therefore, at approx. 4.42 m/s and a diameter of 200 mm, approx. 1.33 Pa/m loss should occur, if the roughness is taken into account. Here I am not sure what exactly the simulation does. I hope you can help me there.
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Hi, the pressure in the post-processor for incompressible simulations is static pressure.
It’s also possible to add one scalar field in the post-processor for total pressure, if you set this result control.
Cheers
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Thank you!
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