The Research Of The Crucial Technology For The Moving Belt Ground Plane In Low Speed Wind Tunnel

The ground effect is a phenomenon that the airplane or other flying vehicles will encounter during the flight near the surface or the takeoff and landing. So it is of great significance to understand the ground effect for the development of the flying vehicles. Two methods for the experimental study of the ground effect are mainly included: flight test and wind tunnel test. The latter is currently preferred means to perform the ground-effect study at home and abroad.Testing methods for the wind tunnel test will include (a) method of image, (b) fixed ground plate and fixed model, (c) fixed ground plate and moving model and (d) moving ground plate and fixed model. Different advantages and drawbacks for such four methods will exist in the requirements for the testing facility, the difficulty in carrying out the test scheme and the effect on the boundary layer of the ground plate. The most effective method to eliminate the interference of the boundary layer is the dynamic ground effect test, i.e., the method of moving model or moving the ground plate. The experiments have shown that the test results of the moving ground plate are much closer to the actual ones than the test results of the fixed ground plate. Therefore, the method of the moving ground plate and fixed model is one of the most useful one to study the ground effect of the flying vehicle. The crucial technology study of the moving belt ground plate plays a very important role in engineering application.The moving belt ground plate is mainly used to study and measure the ground effect of the flying vehicle. The main purpose of developing the moving belt ground plate is to eliminate the ground plate boundary layer and its interference. Compared with the fixed ground plate, the moving belt ground plate will not generate the boundary layer and can simulate the actual ground effect when the moving belt and the airstream have the same velocity and direction. The former has the boundary layer, so great differences will exist between the test results and the actual flight results.The paper firstly introduces the structure and main technical performance of a set of testing device, the moving belt ground plate, which is specially used into the ground effect study, including its supporting mechanism, driven mechanism, high-speed moving belt, flow field generation device, boundary layer measurement device, flow velocity and moving speed of the moving belt ground plate. Then the testing method for this device is described. The boundary layer thickness of various sections under different wind speed is compared with the means of the wind speed probe transversing. Finally, preliminary results of the moving belt crucial technology study are obtained according to the boundary layer characteristic measurement. The application of the moving belt ground plate into the ground-effect study is an unprecedented action in wind tunnel testing techniques in China. It will increase aerodynamic test level and enhance a comprehensive capability of the ground-effect study. Moreover, it will play a significant role in the development of the new-concept weapon and the modernization of the existing armament...