基于内窥式PIV的回流燃烧室冷态内流场测量

Measurement of Non-Reacting Flow Field in Reverse-Flow Combustor Based on Endoscopic PIV

关键词:  航空发动机  内窥式PIV  回流燃烧室  受限空间  内流场

Key words:  Aircraft engine  Endoscopic PIV  Reverse-flow combustor  Confined space  Inner flow field

摘要:

为了突破传统测量光路限制，实现对航空发动机三头部全尺寸回流燃烧室模型试验件内部冷态流场精细化测量，自主搭建了一套内窥式PIV（Particle Image Velocimetry）测量系统，在自模区工况下对其内部冷态流场进行了测量调试。结果表明，在壁面之上预设内窥小孔即可实现测量光路布置，采用大焦距光学适配接口能够很好地解决相机内窥镜成像圈较小的技术难题。通过缩短相机内窥镜工作距离和采取多种消光措施，大幅提高了测量信噪比，最终实现了模型燃烧室内部冷态流场的大视场（65mm×65mm）高分辨率（0.876mm）精细化测量，获得了内部流场结构信息。

Abstract:

In order to achieve fine measurement of the flow field of full-scale three sector aircraft engine reverse-flow combustor with breaking through the limitation of measurement light path， an endoscopic PIV system was built up to measure the inner flow field of the model combustor in itself-stimulated domain. It is found that the small holes in walls could conveniently meet the measurement light path layout， the optical adapter with larger focal length could solve the technical problem of small imaging circle of camera endoscope. The spatial resolution of measurement and signal-to-noise ratio have been substantially increased through shortening the working distance of the laser endoscope and taking a variety of extinction measures. And finally， the inner flow field of model combustor was well measured and the structure information of its inner flow field was achieved.