变循环发动机前涵道引射器简化模型实验与仿真研究

Experiment and Simulation of Simplified Model of Front Variable Area Bypass Injector of Variable Cycle Engine

关键词:  变循环发动机  引射器  前涵道  气动参数  简化模型  实验研究

Key words:  Variable cycle engine  Injector  Front bypass  Aerodynamic parameters  Simplified model  Experimental research

摘要:

以典型前涵道引射器基本构型与气动参数为基础，开展了前涵道引射器简化模型实验研究。通过实验与仿真相结合的方法，研究了变循环发动机在单、双涵道模式下前涵道引射器的气动性能以及不同核心机驱动风扇级（Core driven fan stage，CDFS）旁路出口角度对前涵道引射器气动性能的影响，得到了流量比、压比对前涵道引射器气动性能的影响规律。结果表明，在单涵道模式下，仿真得到的沿程截面的总压分布与实验结果非常吻合，CDFS旁路出口角度对前涵道引射器气动性能的影响可以忽略，而出口总压恢复系数随CDFS旁路喉道马赫数增大而降低。在双涵道模式下，SST k-ω模型能够较好地模拟气流的掺混过程，但在出口总压分布上，实验结果更加均匀；CDFS旁路出口角度对两股气流的掺混影响较小；压比一定时，出口总压恢复系数随出口背压的上升先增大后减小；压比为1.35时，流量比变化1.1，总压恢复系数的变化量约为2.6%，压比为1.19时，流量比变化1.2，总压恢复系数的变化量约为0.46%。

Abstract:

Based on the typical basic configuration and aerodynamic parameters of front variable area bypass injector（FVABI）， the simplified model experiment of FVABI is designed. By means of the combination of simulation and experiment， the aerodynamic performance characteristics of FVABI under the single and double bypasses modes and the effects of different CDFS bypass outlet angles on the aerodynamic performance of FVABI are studied. The effects of the flow ratio and pressure ratio on the aerodynamic performance of FVABI were obtained. The results show that the total pressure distribution at the cross section by simulation is very consistent with the experimental result in the single-bypass mode， the influence of CDFS bypass outlet angle on the aerodynamic performance of the FVABI can be ignored， while the total pressure recovery coefficient decreases with the increase of the CDFS bypass throat Mach number. In the double-bypass mode， the SST k-ω model can simulate the mixing process of two streams well， but the experimental results are more uniform in the total pressure distribution at the outlet. The CDFS bypass outlet angle has less influence on the mixing of the two streams. When the pressure ratio is constant， the total pressure recovery coefficient increases first and then decreases with the increase of the outlet pressure. When the pressure ratio is 1.35， the change of flow ratio is 1.1， the change of total pressure recovery coefficient is about 2.6%， when the pressure ratio is 1.19， the change of flow ratio is 1.2， the change of total pressure recovery coefficient is about 0.46%.