串联式TBCC进气道模态转换模拟器设计及其特性分析

为了实现涡轮基组合循环（TBCC）推进系统平稳模态转换过程的模拟，在前期风洞试验研究的基础上对串联式TBCC进气道模态转换模拟器进行重新设计。采用线性化及非对称的思路对该模拟器进行设计并对其特性展开数值仿真研究。结果表明：该模拟器不仅需要模拟发动机工况改变引起的背压变化，而且能通过流通截面面积线性变化，实现两个通道的流量分配。该装置的特点是能保证模态转换过程中每一点的涡轮/冲压通道的总堵塞比不变，使本文所研究的进气道在总堵塞比保持为65%时进行模态转换，结尾激波基本维持在喉道等直段内且进气道出口马赫数基本维持在0.30，流量系数基本为0.45，涡轮/冲压通道流量呈线性变化，与预期目标一致。

Design and flow characteristics analysis of mode transition simulator for tandem type TBCC inlet

In order to simulate the smooth mode transition of turbine based combined cycle (TBCC) propulsion system, the mode transition simulator for tandem type TBCC inlet is redesigned based on the experiences learned from the high speed wind tunnel test. The linear and asymmetric methods are then used to design this simulator, and its flow characteristics is analyzed through numerical simulation. The results indicate that the simulator is used not only to simulate the change of back-pressure caused by the change of engine operation condition, but also to distribute the mass flow into the two flowpaths linearly during the mode transition. The new simulator can keep the sum of the throttle ratios of turbojet/ramjet flowpaths as a constant in every moment during the process. For the inlet discussed in this paper, when the total throttle ratio is equal to 65% during the mode transition, the terminal shock locates in the throat of the TBCC inlet, the Mach number at the aerodynamic interface plane of this inlet is basically equal to 0.30, the flow ratio of this section is basically equal to 0.45, and the flow ratio into two flowpaths is distributed linearly. This simulator thus can meet the needs of expected goal.