S弯进气道与涡喷发动机进发匹配特性研究

Research on the Matching Performance of S-shaped Inlet and Turbojet Engine

摘要:

靶标推进系统的进发匹配性能对评估发动机的工作特性至关重要。为了获取靶标地面状态进气道与发动机的匹配性能，对某靶标用小型涡喷发动机与背负式 S 弯进气道，采用进发匹配地面台架试验与进气道抽吸试验相结合的方法，开展 S 弯进气道与涡喷发动机的进发匹配特性研究，重点研究 S 弯进气道对涡喷发动机性能的影响；同时，提出一种工程分析方法，建立进发匹配地面台架试验与进气道抽吸试验之间的联系，以评估小型发动机进发匹配条件下发动机地面状态的性能参数。结果表明：进发匹配地面台架状态下发动机性能主要受 S 弯进气道的影响，与工艺进气道相比，连接全尺寸 S 弯进气道后发动机性能降低；随着发动机转速提高，抽吸流量增加，S 弯进气道的性能恶化，进气道出口总压恢复系数降低、流场畸变增加，对发动机性能产生不利影响，导致发动机性能降低，推力降低、耗油率增加；本文提出的工程分析方法可以可靠预测小型发动机进发匹配条件下地面状态的发动机性能，具有一定的工程应用价值。

Abstract:

The inlet/engine matching principle of target drone propulsion system is important to evaluate the engine working characteristics. To obtain the inlet/engine matching performance of a target drone, the investigation of the S-shaped inlet and small turbojet engine matching characteristic is carried out in this paper, by combining inlet/engine matching ground test with inlet suction experiment. It concentrates the influence of the S-shaped inlet on the engine characteristics. And an engineering method is produced to evaluate the small engine characteristics on ground running, by building the connections between the inlet/engine matching ground test and inlet suction experiment. It"s shown that the performance of engine in matching ground test is mainly affected by the S-shaped inlet characteristic parameters. When the full scale S-shaped inlet installed, the engine performance is no longer as good as the craft inlet installed, but falls. As the engine rotating speed enhanced, the mass flow increases, and the inlet performance gets worse. The total pressure recovery coefficient at the inlet exit decreases and the distortion index rises, which has a negative effect on the engine performance, resulting in the thrust smaller and the fuel consumption larger. Moreover, the proposed method can reliably evaluate the small engine characteristic parameters under matching ground condition based on the experimental data, so it is effective on engineering application.