气动光学畸变波前的本征正交分解和低阶近似

应用哈特曼波前传感器测量了准直平行光通过低速热射流流场后的畸变波前时间序列,对该波前时间序列进行了本征正交分解(POD)和低阶近似研究,对比研究了16#,1008#数据点处的低阶近似波前时间序列和测量波前时间序列。结果表明,畸变波前可用本征正交分解基来展开,应用少量的低阶本征正交分解基即可捕捉到波前的主要信息,并且随着重构模式数的增加,低阶近似波前更加逼近测量波前。由于波面上不同位置处相位脉动量的空间相关性各异,因此选用相同的重构模式数时不同数据点处的重构精度也不一样。

Proper Orthogonal Decomposition and Low Dimensional Approximation of Aero-Optical Aberrated Wavefronts

The aero-optical aberrated wavefronts are measured by applying Hartmann wavefront sensor when the collimated parallel beam passes through a low speed heated turbulent jet.Proper orthogonal decomposition(POD) and the low dimensional approximation are applied to the aberrated wavefront time series,the comparisons between the measured wavefronts and low dimensional approximation reconstruction wavefronts of 16# and 1008# were conducted.The results indicated that the aberrated wavefronts can be expanded by the POD group and can be described with a few POD modes,with the more the reconstruction modes the more the reconstruction precision.Due to the difference of the spacial correlation of phase pulsating quantity at different wavefront positions,the reconstruction precision different data points is not same for the same reconstruction modes.