This engine is a heat engine in the Stirling engine. By circulating compression and expansion of air or other gases, the working fluid operates at different temperature levels, converting the thermal energy into mechanical work. The engine is like a steam engine. The heat of all the engines flows in and out through the engine wall. .The engine model switches the flywheel by hand in the horizontal position to see if it is smooth. If there is strong sensation, check if the connecting rod is normal, whether there is oil cylinder and dust. If it is, please use toilet paper to erase it. Switching the flywheel feels that the pressure rebound in the cylinder is normal, the cylinder is sealed .The fuel of this product is butane gas, which can be purchased directly .Ignition step: First press the button to the tank, then dial the above valve, ignite, wait for about 30 seconds to heat, turn the propeller to start, the position of the fuel tank has a knob to adjust the size of the firepower. It can control the speed. For the service life of the model, it is generally not recommended to adjust. Finally close the valve, turn off the fire, be careful, be sure to wait until the natural cooling touch the heating cylinder, so as not to burn .Cycling process: 1. isothermal endothermic; 2. isothermal heating by external heat source; 3. heat, heat; 4. coolant isothermal exotherm, and complete a cycle. .This is an external combustion engine in which the fuel is continuously combusted, and the piston is moved by expansion of air (or helium or hydrogen) as a medium, and the expansion gas is cooled in the cold chamber, and the circulation is repeated. .As an external combustion engine, it avoids the explosion of traditional internal combustion engines to achieve high efficiency, low noise, low pollution and low operating costs. .The maximum advantage and efficiency of the external engine output is affected by the altitude, which is ideal for high altitude areas. .Aerodynamics has rich physics knowledge, intuitive engine principle, educational toys, teaching experimental equipment can effectively cultivate children's learning interest, can also be used for classroom teaching, more intuitive and easy to understand. .A floating bead connects 8 cylinders and their pistons. It is driven by the motor power of hot air. It is hard to believe that it is an engine model, super cool, 8 cylinders, 8 heating tubes .8 fire exits ignite the flame onto the stainless steel heating tube, cool .Note: 1. Due to different displays and different lighting, the picture may not reflect the actual color of the item. thank you for understanding. 2. Please allow a little difference due to manual measurements.