基于曲率指导的B样条飞机进气道几何设计  

Geometric Design of B-Spline Aircraft Inlet Based on Curvature Guidance

作　　者：魏明强[1] 何雪滟 吴梦 郭延文[2] 谭慧俊[4] Wei Mingqiang;He Xueyan;Wu Meng;Guo Yanwen;Tan Huijun(School of Computer Science and Technology,Nanjing University of Aeronautics and Astronautics,Nanjing 210016;State Key Laboratory for Novel Software Technology,Nanjing University,Nanjing 210023;School of Mathematics and Statistics,Nanjing University of Science and Technology,Nanjing 210094;School of Energy and Power,Nanjing University of Aeronautics and Astronautics,Nanjing 210016)

机构地区：[1]南京航空航天大学计算机科学与技术学院,南京210016 [2]南京大学计算机软件新技术国家重点实验室,南京210023 [3]南京理工大学数学与统计学院,南京210094 [4]南京航空航天大学能源与动力学院,南京210016

出　　处：《计算机辅助设计与图形学学报》2023年第12期1822-1832,共11页Journal of Computer-Aided Design & Computer Graphics

基　　金：国家自然科学基金(T2322012,62172217,62032011).

摘　　要：进气道能够捕获来流,按一定流量、流速和畸变向发动机供气.作为飞机推进系统的起始部件,进气道直接影响飞机发动机的工作效率、性能和安全性.针对进气道自由曲面构型的特点,提出基于曲率指导的B样条进气道几何设计方法.首先给定控制点、节点数据,构造C2光滑约束的B样条关键截线,避免产生台阶效应而影响进气道性能;其次将计算过渡截线的离散点坐标,转化为利用过渡截线导数值反求所对应的B样条曲线,减小在复原曲线过程中计算离散点带来的累积误差;最后将上述B样条曲线拟合为B样条张量积曲面结构,减少格式转换造成的信息损失.该方法已集成在某型号进气道建模系统中,可快速、交互式地完成由任意进气口截线到出气口截线的光滑过渡.实验结果表明,建模得到的进气道曲面结构精确性较高、通用性较好,一定程度上减少了对国外相关CAD航空工业软件的依赖,可以为后续基于数值优化的几何设计与流体仿真一体化提供技术支撑.Air inlets are the initial component of the aircraft propulsion system,which is responsible for capturing the incoming flow and supplying air to the engine according to a certain flow,velocity and distortion.Thus,they affect both the efficiency and effectiveness of aircraft engines.Aiming at the configuration of the free-form surface of the air inlet,a B-spline fitting algorithm based on curvature guidance is proposed for inlet geometric design.First,under the premise of given control points and node data,B-spline key section lines with C2 smooth constraints are constructed to avoid the side effect of staircases which will degrade the performance of the inlet;second,to reduce the error caused by the discrete points in the process of restoring the curve,the step of calculating the coordinates of the discrete points of the transition section is transformed into the reverse calculation of the corresponding B-spline curve by using the derivative value of the transition section;finally,the above B-spline tensor product surface structure is fitted to reduce the information loss caused by format conversion.The method has been packaged into an inlet modeling system,which can quickly and interactively achieve the arbitrary transition from the air inlet intercept line to the air outlet intercept line.The experimental results show that the obtained inlet surface structures are of high accuracy and possess the generalization ability.Our method can reduce the dependence on foreign CAD related Aviation Industry Software,and provide technical support for the subsequent integration of geometric design and fluid simulation based on numerical optimization.

关 键 词：飞机进气道 几何建模 曲率指导 B样条曲面拟合 

分 类 号：TP391.41[自动化与计算机技术—计算机应用技术]