基于响应面的变复杂度气动分析模型

Improving Variable Complexity Model(VCM) for Aerodynamic Analysis

结合变复杂度和响应面近似建模方法,采用CFD和工程估算气动分析方法,构建了基于响应面校准的变复杂度气动分析模型。以冲压发动机导弹为例,采用拉丁超方取样技术,选取6个CFD计算状态,建立了差值和比值校准响应面,并比较校准后的气动性能与CFD分析。结果显示,基于差值校准响应面的变复杂度方法具有较好的逼近能力和计算效率,适合于飞行器多学科设计优化过程的气动分析。

Purpose. The VCM, when applied to MDO（Multidisciplinary Design Optimization） of flight vehicle is, in our opinion, deficient in computational accuracy of aerodynamic discipline. We propose using RSM（Response Surface Model） as the correction model of VCM for improving the computational accuracy of aerodynamic discipline of MDO process. In the full paper, we explain in detail how to use RSM; in this abstract, we iust list the two topics of our explanation： （1） the VCM for aerodynamic analysis based on response surface ; mathematically speaking, the explanation under this topic includes the derivation of eqs. （1） through （4） in the full paper; （2） aerodynamic computational model of missile; the subtopics are lowprecision model of analysis（subtopic 2. 1） and high-precision model of analysis（subtopic 2. 2）;subtopic 2. 1 includes eqs. （5） through （9） in the full paper. Finally we give a ramjet missile example. Utilizing the Latin Hypercube Sampling （LHS） technology, we chose six reference flight states and constructed the additive and multiplicative response surface models of correction. We used Table 1 and Figs. 4 and 5 in the full paper to compare the aerodynamic performances corrected by us with CFD data. The results show preliminarily that, with additive response surface correction model, VCM has excellent approximation performance.