Summary: | 碩士 === 國立中興大學 === 機械工程學系 === 93 === Although the size of model plane is smaller, and the flight range is much shorter than real airplane, the principles of flight are as the same as real airplane. The model planes are generally powered by internal combustion engine or electric motor. If using the compressed air as the power source to activate piston for rotating the propeller in order to attain thrust. As long as matching right airplane shape and aerodynamics, a model plane without fuel oil or battery will soar in the sky. In this research, we use the carbonated beverage PET bottle as the pressure container for this model aircraft, with high strength for resisting pressure, light, and streamline shape matching the property requirement. In order to make model plane to fly well, we have to recognize the factors that influence the flight, such as lift, weight, thrust, and drag. Moreover, if we want to make plane flying steady, we should consider the influences of : the stabilizer for pitching, the fin and sweep of wing for yawing, and dihedral wing for rolling. The shapes of airfoil and plane, the c.g. position are the problems that should be solved in the research process. The engine is the heart of the airplane, the performance of the opposed-type engine with double piston used in this experiment is better than the conventional single-piston engine. Now the farthest distance that our air-powered model plane can fly is 120 meters. In the future, we may develop a better engine and better plane shape for advancing aerodynamics in order to extend flight range further.
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