The invention relates to a
natural gas engine structure for mixed double-injection of cylinder outer cold water and in-cylinder hot water. The
natural gas engine structure comprises a
natural gas engine body, an air
inlet manifold, an
exhaust manifold, a natural gas
injector, a
spark plug, an in-cylinder water
sprayer, a high-pressure water pump unit, a cylinder outer water
sprayer, a low-pressurewater pump unit, a
heat exchanger and a
electronic controller; and the in-cylinder water
sprayer is arranged in the natural
gas engine body, the high-pressure water pump unit communicates with the in-cylinder water sprayer, the cylinder outer water sprayer is arranged in the air
inlet manifold, the low-pressure water pump unit communicates with the cylinder outer water sprayer and the electroniccontroller is electrically connected with the natural gas
injector, the
spark plug, the in-cylinder water sprayer, the high-pressure water pump unit, the cylinder outer water sprayer and the low-pressure water pump unit. Compared with the prior art, the natural
gas engine structure has the advantages that hot water sprayed in a cylinder is used for rapidly vaporizing to absorb heat, so that the temperature in the part, close to a
combustion top dead center, of the cylinder is reduced, and the generation of knocking is inhibited; meanwhile, the heat for heating the water comes from recovering
tail gas energy by a exchanger, so that the working medium in the
combustion process is increased, the heat loss is reduced, and the heat efficiency of the natural
gas engine is improved.