Two Phase Water Jet Propulsion for High-Speed Vehicles

A water jet propulsion apparatus having an engine producing an exhaust gas, a pump driven by the engine, a nozzle in fluid communication with the pump, and an exhaust passageway communicating between the engine and the nozzle is disclosed. The exhaust passageway is connected to the nozzle at a point in the nozzle where the water flow velocity is being increased, and prior to the water being expanded. By mixing the exhaust with the water while the water flow velocity is being increased, the result is a decrease in the density of the mixture and an increase in the total mass flow rate, thus resulting in increased thrust.