Approach of Viscous/Potential Flow Based on Helmholtz Velocity Decomposition

Abstract

Abstract: Abstract： According to Helmholtz velocity decomposition, a modified NavierStokes(NS) equation was obtained by decomposing the velocity into the potential flow component and the remaining one. The solution to the modified NS equation was only for the remaining velocity component which vanished in the far field. It was highly efficient to solve the modified NS equation due to the request of small computation domain. Such viscous/potential flow solver was developed on the platform of open source software OpenFOAM. The flows around a cylinder were simulated by the present method in which the analytical formula was taken as the solution to the potential flow. The calculations of the flow around a cylinder at different Reynolds numbers and the comparison of the results with the ones obtained by using the conventional computational fluid dynamics method and the experiment data were conducted. The results agree well, which indicates that the present method is suitable to solve both laminar and turbulence flow and it can improve the computational efficiency.

Key words: potential/viscous, OpenFOAM, modified NS equation, Helmholtz, flow around a cylinder

CLC Number:

U 661.3

ZHAO Ji,ZHU Renchuan,MIAO Guoping. Approach of Viscous/Potential Flow Based on Helmholtz Velocity Decomposition[J]. Journal of Shanghai Jiaotong University, 2016, 50(01): 103-109.

References

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