Overexpansion high-thrust exhaust nozzle capable of preventing shock waves from entering jet tip

The invention discloses a novel overexpansion high-thrust exhaust nozzle capable of preventing shock waves from entering a jet tip. The overexpansion high-thrust exhaust nozzle is formed by connecting a conventional shrinkage and expansion nozzle section and a sawtooth-shaped ring structure. The ring surface where the sawtooth-shaped ring structure is located is tangent to the ring surface of the shrinkage and expansion nozzle section instead of an extension of the ring surface of the expansion section. The sawtooth-shaped ring surface has a certain outward deflection radian relative to the extension ring surface of the expansion section. According to the novel engine exhaust nozzle obtained by means of appearance change, compared with a Laval nozzle of the same specification, when a prototype nozzle works under the working condition that the shock waves are caused in the jet tip due to overexpansion, the novel nozzle can effectively control the shock waves while overexpansion is performed under the same working condition, the shock waves cannot enter the jet tip, gas flow at an outlet of the nozzle is still kept at the supersonic speed, and thrust losses are not brought about. Meanwhile, the barometric pressure presses the shock waves to be attached to the sawtooth-shaped ring structure of the nozzle, the thrust can be greatly increased, and accordingly the overexpansion high-thrust effect is achieved.