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直升机机身阻力是飞行阻力的主要来源之一,通过对机身外形的优化设计,能够实现直升机的高效低阻飞行。首先,把机身划分为头部、中段和尾梁三段,对其外形轮廓线进行CST参数化表示;其次,采用拉丁超立方法选取试验设计样本点,计算各样本点的阻力系数,构造Kriging代理模型,估计模型预测的精度;最后,选用序列二次规划算法对其进行优化,并对优化后的机身模型进行了风洞试验。通过计算分析可知:所建立的Kriging代理模型能够精确预测阻力系数值,优化后得到了机身的设计参数;机身阻力系数减小了15.3%,理论值与试验值吻合良好。
Helicopter body resistance is one of the main sources of flight resistance. Through the optimized design of the fuselage shape, it is possible to realize the helicopter’s high efficiency and low resistance flight. First, divide the fuselage into three sections of head, middle section and tail beam, and then CST parametrize the outline of its outline. Secondly, using Latin hypercube method to select the sample points of the test design and calculate the drag coefficient of each sample point, Kriging proxy model to estimate the accuracy of the model prediction. Finally, the sequence quadratic programming algorithm is used to optimize it, and the wind tunnel test of the optimized fuselage model is carried out. Through the calculation and analysis, it can be seen that the established Kriging proxy model can accurately predict the drag coefficient, and the optimized design parameters of the fuselage. The body drag coefficient is reduced by 15.3%, and the theoretical value is in good agreement with the experimental data.