ACTA AERONAUTICAET ASTRONAUTICA SINICA >
An improved Green's function method for pressure distribution calculations
Received date: 2014-07-06
Revised date: 2014-08-07
Online published: 2014-09-17
Supported by
National Defence Pre-research Foundation of China (9140A25010312HK03295)
An improvement on the pressure distribution calculations in the Green's function method is presented. Although the Green's function method can give some very accurate results in velocity potential calculations, in pressure distribution calculations, the accuracy of the results is not good becaused in this method a very simple formula evaluated by finite difference method is used to get the pressure distributions on the surface of the body. In the present paper we use a different method to calculate the pressure distributions. We differentiate both side of the algebraical velocity potential equation and get the analytic expressions of the derivatives of the velocity potential along the x,y,z directions respectively, then we use these formulas to calculate the pressure coefficients and get the pressure distributions on the body. The results are very accurate and in good agreement with the results of Navier-Stokes solver and the experimental data.Moreover we have also made some improvements on the numerical applications of the Kutta conditions and render the results of the calculation more accurate.
Key words: Green's function; potential flow; unigueness; pressure coefficient; Kutta condition
LIU Qiangang , ZHOU Zhou . An improved Green's function method for pressure distribution calculations[J]. ACTA AERONAUTICAET ASTRONAUTICA SINICA, 2015 , 36(6) : 1744 -1751 . DOI: 10.7527/S1000-6893.2014.0209
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