尾喷流吸入对发动机进气畸变的影响

为了研究折返的尾喷流吸入对发动机进口流场畸变的影响特点,开展了发动机不同状态下的尾喷流吸入地面试验,基于测取的发动机进口温度、压力流场数据,分析了发动机进口流场温度、压力畸变特征和影响进气温度畸变强度的因素。结果表明:折返的发动机高温尾喷流吸入会在发动机进口形成明显的温度畸变,此时的发动机进口流场具有温度、压力组合畸变特征;高温尾喷流的吸入会影响发动机进口总压分布,使低压区压力有所升高,总压不均匀性降低;发动机工作状态越高、加力状态保持时间越长,发动机进口形成的温度畸变强度峰值越大;发动机进口温度场的改变滞后于油门杆的动作,是一个动态变化的流场,但尾喷流吸入造成的温升率较小。 

Influence of exhaust gas ingestion on engine inlet distortion

In order to understand the distortion characteristics of the engine inlet face due to exhaust gas ingestion, a ground test was done to acquire the total pressure and total temperature data of the engine inlet face. Based on the measurement data, an analytical study on the features of the temperature and pressure distortion and the influences on the temperature distortion intensity were carried out. The results showed that the deflected exhaust gas can be ingested by the inlet, which could produce a temperature distortion on the engine inlet face, in this situation the flow field on the engine inlet face was a combination of temperature and pressure distortion. The hot exhaust gas ingestion can raise the pressure in the low pressure region on the engine inlet face, and lower the steady pressure distortion. As the engine working thrust lever was improved and the working time was increased, the temperature distortion intensity peak was higher. The change of the temperature flow field lagged behind that of throttle, indicating a dynamic changing flow field, but the temperature rise rate was relatively low.