Design And Optimization Research On Air Turbo Rocket

Air Turbo Rocket(ATR) is one of the Turbo based combined cycles. ATR has the advantage of specific thrust and specific impulse and can be used as the power of weapons. In this thesis, a thermodynamic model for ATR design point analysis is established, consider of the specific heat variation and the mixing of gas and air. The numerical Newton-Raphson iterative approach is applied for the off-design analysis, using scaling law of the known component performance map. Preliminary scheme of air turbo rocket system is designed.The specific impulse, denseness impulse, specific thrust, temperature of combustor gas and specific radio of gas are compared in order to choose the proper propellant. The kerosene and liquid oxygen is choosed as ATR’s propellant in this paper. A new design parameters region divising method is presented, and used to evaluate the influence degrees of design parameters on ATR performance in a 6-level mode basing on parameter sensitivities. The influence of compressor pressure radio, turbo pressure radio, temperature of turbo inlet gas and flight condition on the ATR performance and other paramaters is analysed.With the off-design model, the behavior of gas discharge, the behavior of altitude and the behavior of speeed are investigated. The study shows that: 1) when the relative rotor speed falls, the ATR performance drops, with the ATR working point, the compressor pressure radio, the air mass flow and the gas mass flow going down; 2) when the flight Mach number is low, the specific impulse slowly goes down, the specific thrust rise up, with increasing the Mach number; 3) when the flight Mach number is high, increasing the Mach number will rise specific thrust and decrease the specific impulse. The primary design and choosing of compressor, turbo, mixer, gas generator, combustor and nozzle is carried out. The ATR total weight and size is evaluated base on the component size and conformation.In order to improve the ATR performance, the idea that adding outside air flow is put forward and studied. The ATR performance along 25 kpa and 33 kpa flight dynamic pressure trajectory is calculated. The pre-cool’s function on ATR is studied with the highest temperature limit, 160 K. The different compressor models’ affcetion on ATR perforamce is studied. The results show that pre-cooling, excellent compressor model and adding outside air flow have deeply affection on improving ATR performance and spreading the flight bound.Primary design of vehicle powered by ATR is conducted with the limit of mission. The result shows that compared with tradition vehicle, the one powered by ATR needs better aerodynamics performance and larger lift-drag radio. The optimization of ATR besed on vehicle is conducted.