ABSTRACT
The «at plate boundary layer analysis we introduced in the last chapter represents the „rst line of attack in trying to determine values for the convective transport coef„cients. A great many systems can be regarded as «at plates if their curvature is suf„ciently small. Unfortunately, there are an equal number of technologically important systems where the «at plate analysis fails. Flow over highly curved blunt objects such as cylinders and spheres and «ow in tubes and conduits are two of the most important examples. The failures arise because the boundary layer cannot grow in the same, unbounded manner characteristic of the boundary layer on a «at plate. In «ow over curved objects, the boundary layer separates from the solid surface and forms a wake where the «ow changes direction and recirculates back toward the object. In addition, for «ow within a tube, the size of the boundary layer is restricted to the radius of the tube. In this chapter we will discuss boundary layers in these situations and try to determine theoretical values for the convective transport coef„cients.
