五孔探针流场测试分形插值算法适用性研究OA

In order to explore the effectiveness of the fractal interpolation algorithm applied to the five-hole probe flow field test,two kinds of five-hole probe calibration for gas turbine flow field test are completed through the standard wind tunnel test,and the angle calibration coefficients,total pressure and static pressure calibration coefficients are obtained.The fractal interpolation algorithm is proposed to order the calibration data,and the results are compared with those of the polynomial fitting interpolation.Most of the original angle-calibration coefficient curves of two probes are convex quadrilateral,and there is obvious symmetry with respect to 0 ° yaw angle and 0 ° pitch angle,which proves that the probe design and machining quality are satisfactory.The interpolated values of angle calibration coefficient,total pressure and static pressure coefficient of the established 3D interpolation model are almost identical with those of the original sample,which verifies the validity of the 3D interpolation model.The interpolated values of the 2D polynomial fitting interpolation method at individual edge points and internal nonlinear feature points show large deviations from the original measurements,and there is almost no difference at most points,indicating that the polynomial fitting interpolation method is only valid within the calibrated angle range and is unsuitable for extrapolation beyond it..Compared with the 2D polynomial fitting interpolation method,the interpolated value of fractal interpolation method is closer to the original data,which can avoid the Runge phenomenon inherent in polynomial fitting interpolation at boundary and internal nonlinear characteristic points,and verify the effectiveness of the fractal interpolation method applied to five-hole probe calibration.