Abstract: Disclosed in the present invention is a method of generating a high-speed gas flow, utilizing a device comprised of a gas pipe, a circulating pipe and a starting and controlling system. The starting and controlling system is comprised of one or a combination of any two or more of a refrigerator, a circulating pump and a heat exchanger. The method comprises the following operation steps: filling the device with a working medium; activating the starting and controlling system; after having been pressurized under liquid state, the working medium absorbing heat and being gasified, entering the gas pipe, and generating the high-speed gas flow. The method may utilize a low quality heat source to convert a low-speed gas flow into a high-speed or extremely high-speed gas flow with relatively high use value. Thus, thermal energy carried by the fluid in the nature may be converted into mechanical energy efficiently.