基于响应面法的某双体飞艇囊体气动外形优化

为了进一步减小阻力,提高整个飞艇的气动性能,针对某双体飞艇囊体的长宽比、宽厚比和最大截面位置三个主要外形参数,采用试验设计和响应面法相结合的方法进行了囊体气动外形优化设计,以CFD数值计算技术的结果为基础,共进行了15次试验。优化前,囊体零升阻力系数为0.029 8;优化后,其零升阻力系数为0.027 4,减小了8.76%,巡航状态升阻比增加了5.25%,整个飞艇的气动性能得以较大改善,也证实了优化模型的有效性。研究表明:基于Box-Behnken设计和响应面法的双体飞艇囊体气动外形优化设计方法,不但考虑了外形参数之间的交互作用,而且计算量相对较小,计算结果的精度和可靠度较高,可以快速准确地优选出囊体外形参数的最优组合,具备一定的工程实用价值。

Aerodynamic Configuration Optimization of Hull of a Hybrid Airship

In order to reduce the drag and improve the overall aerodynamic performance of the double-hull airship,the experiment design and response surface method are used to optimize the ballonet shape on basis of three design parameters,including length-diameter ratio,width-thickness ratio and location of the maximum section.The method is based on the CFD results.Fifteen experiments are performed.Before the optimization,the zero-lift drag coefficient is 0.029 8,and after the optimization,the zero-lift drag coefficient is 0.027 4,with a decrease of 8.76%,while the cruising lift-drag ratio is increased by 5.25%.As a result,the overall aerodynamic performance of the airship is improved greatly,which confirms the effectiveness of the optimization model.It indicates that the aerodynamic optimization of the hull of the double-hull airship which based on Box-Behnken design and response surface method not only takes into account of the interactive effects of the shape parameters,but also has a relatively small calculation work,high accuracy and reliability.It can be used to select the optimal shape parameters of the hull quickly,which is valuable in engineering application.