Application of a wide-range nozzle with a central body in ultralight launch vehicles

Gas flow in nozzles of “aerospike” jet engines of two types (with full-size cone and with truncated wedge serving as a central body) is simulated numerically. Thrust parameters of jet engines of superlight launch vehicles depending of flight altitude are studied numerically and analyzed. Aerodynamic aerospike nozzles can be an effective alternative to the traditional conical nozzle, in which exhaust gases exit the combustion chamber and expand not quite correctly, losing the sufficient part of the engine thrust. An aerospike jet engine naturally compensates the changes in atmospheric pressure. Instead of expanding the gases along the fixed generators of the conical nozzle, the wedge-shaped central body expands the gases along the fixed wall of the central body, which provides thrust avoiding losses due to difference between exhaust pressure and ambient one.