| 摘要 |
The rocket propulsion unit for space flight comprises a low altitude thrust nozzle (3) and an axially movable (9) high-altitude nozzle (4) which is initially retracted and is extendable such that its forward end connects with the rear end (3b) of the nozzle (3). Up to a height of 12-14 km, the nozzle (3) acts as over-expansion nozzle producing a thrust flow (5) exit pressure of 0.2-0.15 bar whilst the retracted nozzle (4) has its rear end (4b) a little behind the end (3b) of the nozzle (3) and, together with that nozzle (3) and its thrust flow (5), defines an annular outer thrust system (6). The system has a convergent-divergent nozzle passage (7) providing an outer thrust flow (8) subject to injector action by the flow (5). At 12-14 km height or 0.2-0.15 bar ambient pressure, the outer nozzle (4) is fully extended, this nozzle being designed such that it then acts as over-expansion nozzle with a thrust flow exit pressure of 0.03-0.02 bar.
|
