航空发动机地面试验激光燃烧诊断技术研究进展

为了研究湍流燃烧基础问题和改进实际燃烧装置性能，基于激光的燃烧诊断技术已发展成为当前发动机湍流燃烧实验研究的主要测量工具。在已发展的激光燃烧诊断技术中，每种技术都有其局限性和适用范围，需要根据发动机模型燃烧室内部流场测量的要求和特点，选择合适的激光诊断技术。在温度测量中，相干反斯托克斯拉曼散射（CARS）技术主要用于单点温度测量，单脉冲CARS谱测温不确定度优于5%；高时空分辨温度场的测量需要采用双色平面激光诱导荧光（PLIF）测温方法，但其测温精度通常也会相应降低。在速度测量中，粒子成像测速（PIV）技术适用于低速流场速度的精细测量，羟基分子标记测速（HTV）技术适用于高温超声速甚至高超声速流场的速度测量，HTV测速不确定度可优于4%。在组分浓度测量中，主要采用自发拉曼散射（Spontaneous Raman Scattering，SRS）和PLIF技术进行主要组分和中间反应物的浓度分布测量。本文对航空发动机湍流燃烧温度、速度、组分浓度等参量的高时空分辨测量所涉及的激光燃烧诊断技术的基本原理、研究现状和发展趋势进行综述。

Development of laser combustion diagnostic techniques for ground aero-engine testing

Laser-based diagnostic techniques have the characteristics of non-intrusiveness, high temporal-spatial resolution and abundant measurement information, and have been demonstrated as powerful and indispensable tools for the turbulent combustion research of various engine devices.This paper reviews the basic principle, research status and development trend of several laser spectroscopic techniques, which have been used successfully in the measurements of engine combustion.Since there is no single laser diagnostic technique that can be applied under all circumstances, the particular application must be carefully considered according to the type of combustion flow and measurement requirements.For the temperature measurements, Coherent Anti-stokes Raman Scattering (CARS), as a point-wise technique, yields the best accuracy of less than 5% uncertainty for single-shot measurements.And the two color Planar Laser Induced Fluorescence (PLIF) technique may be employed to study temperature gradients or temperature fields but may lead to reduced absolute accuracy.For the velocity measurements, the Particle Image Velocimetry (PIV) technique is suitable for fine measurements of low-speed flow field, while the Hydroxyl Tagging Velocimetry (HTV) technique has been applied in high-temperature supersonic and even hypersonic flow fields with uncertainty less than 4%.In species concentration measurements, the Spontaneous Raman Scattering (SRS) and PLIF are used to measure the main components and the distribution of intermediate products, respectively.In terms of the high-temporal-spatial-resolution measurements of temperature, velocity and species concentrations in the aero-engine combustor, this paper reviews the basic principle, research status and development trend of relevant laser combustion diagnostic techniques.