Initiation of operation of a ramjet engine with distributed fuel injection along the combustion chamber is studied numerically. A principally important issue is the presence of a compressed air jet producing a throttling effect and preliminary deceleration of the flow to transonic velocities. The Reynolds-averaged Navier-Stokes equations closed by the SST k-ω turbulence model are solved. Hydrogen is used as a gaseous fuel. Transverse injection of the fuel is considered. A pulsed transonic flow regime is obtained. It is demonstrated that the characteristic scale of vortex regions increases with an increase in the stagnation temperature approximately to 1700 K; consequently, the degree of air-hydrogen mixing is significantly enhanced.

数值研究了沿燃烧室分配燃料喷射冲压发动机的启动过程。一个主要的重要问题是压缩空气射流的存在，它会产生节流作用，并使气流初步减速成跨音速。求解了由SSTk -ω湍流模型封闭的雷诺平均Navier-Stokes方程。氢气用作气态燃料。考虑燃料的横向喷射。获得脉冲跨音速流态。结果表明，涡流区域的特征尺度随着停滞温度的升高而增大，直至大约1700 K；而随着温度的升高，涡旋区域的特征尺度逐渐增大。因此，空气-氢混合的程度显着提高。