Thrust nozzle for rocket drive with variable expansion ratio - uses ring-shaped device, and circumferential injection of gaseous liquid medium to detach nozzle flow

摘要

The thrust nozzle has variable expansion ratio. It is arranged for max. expansion ratio. Devices located in a ring-shape on the circumference of the lower expansion section cause the nozzle to detach the nozzle flow, and prevent further expansion. Switching or removal of the devices, reverses the detachment of the nozzle flow, and frees the next largest expansion ratio. Detachment is by injection of e.g. gases or easily gasified fluids. The injection medium may be separate, or may consist of the fuels carried, pref. non-oxidyzing fuels. Alternately, it may consist of ambient air, which is taken in through circumferential apertures. These are closed automatically by non-return valves, when the ambient pressure drops, resp. relative internal nozzle pressure rises. The medium may also be formed by pressure gases of the turbopump. ADVANTAGE - Optimum performance with lowest risk and expenditure.