What is the difference in cfd when the flow is not compressible?
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When the flow is not compressible in Computational Fluid Dynamics (CFD), the simulation results may differ from experimental values due to the neglect of weak compressibility. Various studies have shown that considering weak compressibility in CFD simulations can lead to results closer to experimental values, especially in applications like water-cooled intercoolers and pump turbines. Additionally, the use of collocated grid-based CFD methods for flows past wind turbines emphasizes the importance of pressure-velocity coupling, with newer methods showing improvements in convergence rates and accuracy in turbulent flow computations. Therefore, accounting for weak compressibility in CFD simulations can enhance the accuracy of results, particularly in scenarios involving complex geometries and turbulent flows.
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| Papers (4) | Insight |
|---|---|
1 Citations | Considering weak compressibility in CFD simulations of pump turbines improves accuracy by aligning numerical results closer to experimental data, enhancing performance evaluation. |
16 Jun 2014 | In CFD, for incompressible flow computations, pressure-velocity coupling methods like Rhie-Chow's can lead to time step-dependent solutions, affecting convergence rates, but newer methods offer time step independence. |
| In compressible flow CFD simulations for water-cooled intercoolers, the compressible model provides closer results to experiments compared to incompressible models, with deviations of 6.5% in heat transfer and 7.5% in pressure loss. | |
| Not addressed in the paper. |
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