This is an example of the flow of a fluid over an object the flow region around the object may be divided into three regions. near the body, the fluid develops a shear layer where viscosity and/or turbulence is important. The book also says that the velocity of the fluid must be zero relative to the body on the surface of the body. This means the velocity of the fluid near the object surface is the same as the object. I want to ask, is the velocity near the surface always is the same with the object. I mean even if at the start, the fluid element may not have the same velocity as the object but as time pass by and become steady, the fluid element may achieve the same speed of the object, is it? BTW, shear layer simply means a closed surface that has the same shape of the object, is it?