LNG power system based on fixed-pitch propeller

The invention discloses an LNG power system based on a fixed-pitch propeller. The LNG power system comprises a gas supply system, a gas engine, a hydro-viscous clutch and the fixed-pitch propeller. The input end of the gas engine communicates with the output end of the gas supply system so that the gas supply system can provide gaseous natural gas output power. The input end of the hydro-viscous clutch is connected with the output end of the gas engine, and the output end of the hydro-viscous clutch is connected with the input end of the fixed-pitch propeller so that power output by the gas engine can be transmitted to the fixed-pitch propeller. The hydro-viscous clutch adjusts the power transmission mode based on the operation condition of the fixed-pitch propeller. According to the LNG power system based on the fixed-pitch propeller, the hydro-viscous clutch correspondingly adjusts the transmission mode of the power output by the gas engine based on the operation working condition of the fixed-pitch propell