桥梁主梁断面气动特性计算

采用雷诺平均Ｎａｖｉｅｒ－Ｓｔｏｋｅｓ方程和在连续方程增加压力对时间导致数项的拟压缩性方法，计算桥梁主梁断面气动特性，数值计算过程采用基于中心差分近似和Ｒｕｎｇｅ－Ｋｕｔｔａ时间推进的格点有限体积多重网格法，湍流模式采用Ｂａｌｄｗｉｎ－Ｌｏｎｍａｘ代数模式，以虎门桥主梁断面计算为例，计算的空气动力特性与风洞试验数据吻合很好，本文方法具有占机内存小，计算时间短的优点。

COMPUTATION OF THE AERODYNAMIC CHARACTERISTICS ABOUT A CROSS SECTION OF A BRIDGE MAIN GIRDER

In this paper, to compute the aerodynamic characteristics about a cross section of a bridge main girder, the Reynolds-averaged Navier-Stokes equations and the method of pseudocompressibility, in which a time derivative pressure term is introduced into the equations of continuity conservation, are applied. In the numerical procedure, the cell vertex multigrid scheme of finite volume method, which is based on the central difference approximations and Runge-Kutta time stpping, is used. And also, the Boldwin-Lomax algebraic turbulent model is used. As a matter of fact, the computation of the flow past the cross section of the main girder of the Humen bridge is done with the present method. It is found that the computed aerodynamic characteristics is in good agreement with that from the wind tunnel data. Numerical application shows that the present method needs less computer storage and CPU time.