Conventional Helicopter Shape Parametric Design And Its Application

The shape design of a helicopter has a very important influence on the development cycle and the cost of the helicopter. At present, the parametric design has been applied successfully in cars, ships, fixed-wing aircrafts and so on. This paper mainly do researches on the configuration design of conventional helicopter.In this paper, the conventional layout helicopter is divided into several component: rotor, rotor-tail, vertical fin, horizontal fin, landing gear and main body. After analysis of each one, join the necessary parameters as less as possible to establish the corresponding model. The rotor, rotor-tail, empennage is building by mathematical method based on geometric constraints; For the part of landing gear, it is classified into wheel type and skid type; For the body part, the model is based on a kind of ROBIN body. After modeling of each component, they are combined into a parametric model of helicopter’s overall body according to parametric constraints. On the basis of this parametric methods, a user oriented modeling software is developed. The user can change the parameter value accoding to requirements to obtain the wanted model file and save it.The overall scheme design is studied based on the parametric method above. The helicopter overall parameters are obtained by means of emprical formula and data statistics, then the parameters are optimized according to the power constraints and flight constraints. Select an example, get its overall parameters according to the above methods, then the parameters in the model are assigned based on the overall parameters to obtain the example shape model. Later it’s demonstrated in the software above to judge its rationality on one hand. on the other hand, calculating its aerodynamic characteristic using CFD method to judge its performance, using Momentum source instead of the effects of rotors, building grid system in ICEM, the flow field around the case at low speed is calculated in FLUENT. The analysis about the cause of the flow, rotor wake and whole aerodynamic force verified the effectiveness and feasibility of the method in this paper.