Correcting aero-optical wavefront aberration of the supersonic mixing layer based on periodic pulse forcing

Abstract

A correction strategy for correcting the aero-optical wavefront aberration of the supersonic mixing layer is presented based on flow control that is implemented by periodic pulse forcing. The flow field of the controlled supersonic mixing layer is simulated by large eddy simulation, and the optical transmission trajectory of the incident beam is computed by the ray-tracing method. The key component of the correction strategy is a compensation signal employed to correct the aberrated wavefront, which is produced according to flow and control parameters. Three numerical examples, including cases of an incident beam at different streamwise locations, flow control with different pulse periods, and vortex evolution in a pulse period, are performed to test performance of the correction strategy. The numerical results indicate that the correction strategy has a great effect in perfecting the aberrated wavefront again, and hence the far-field beam quality is also improved remarkably. In the end, the possibility of experimental implementation of the presented correction strategy is discussed.

Cellular automata ray tracing in two-dimensional aero-optical flow fields

“…(detached eddy simulation, DES) [19] 依次计算出下一个光线矢量 [20,21] , 进而得到流场区 域内光线的路径. 该方法能有效地处理激波处的折 射率突变, 具有较高的精度 [22,23] .…”