【摘要】 本文采用在《层流边界层的有限差分计算》一文中所提出的处理方法来进行平板湍流边界层的计算,目的在于运用并改进Cebeci and Smith的计算方法（CS方法）。 在本文中仍然采用隐式差分格式,其网格图形为水平的“T”形。根据离前缘距离的不同,沿流动方向分别取一点、二点或三点的一侧差商。根据离壁面及边界层外边界垂直距离的不同,沿垂直方向分别取一侧、半侧或中心的五点差商。 为了工程应用上的简便,湍流模式采用零方程,即湍流剪应力的补充方程采用Prandtl的混合长度理论。讨论并选取了合适的坐标变换、k₂及γ的数值。从计算结果来看,本文所拟定的解题步骤及所编制的计算机计算程序是可行的,具有较高的精度和稳定性,并且得到了比Cebeci和Smith更符合实验的结果,数据也较完整。更多还原

【Abstract】 In the former paper entitled "Finite Difference Method of Laminar Boundary Layer"[1], an effective finite difference method was proposed. In this paper the same method is extended and used to calculate the flat plate turbulent boundary layer.We solve the problem by an implicit finite difference method of a grid point pattern in the shape of a horizontal "T" . In the flow direction one-point, or two-point, or three-point backward difference formula is used respectively according to the distance between the grid point and the leading edge. In the vertical direction one-side, or semi-one_side, or central five-point difference formula is used respectively according to the distance between the grid point and the flat plate wall or the outer edge of boundary layer.The zero-equation model of turbulence is used for the sake of simplicity for engineering application, i.e. the Reynolds shear-stress term may be eliminated by the concept of Prandtl’s mixing length theory. The different forms of coordinate transformation and the different values of k2 and r are discussed and chosen. The non-dimensional transformation isThe proposed values of k2 and r arek2 = 0.022With such an improvement the numerical results obtained in this paper agree better with the experiment and more complete than those of Cebeci and Smith(CS).更多还原