Fluid Friction in Steady, One-Dimensional Flow

In Chap. 5 we found the working form of Bernoulli s equation (Eq. 5.7) 

The form of the friction-loss term is very dependent on the geometry of the system. The problem is much simpler if the flow is all in one direction, as in a pipe, rather than in two or three dimensions, as is flow around an airplane. Therefore, first we consider fluid friction in long, constant-diameter pipes in steady flow. This case is of great, practical significance and is the easiest case to treat mathematically. The starting and stopping of flow in pipes is discussed in Sec. 7.4. I 

In Sec. 6.14 we consider the frictional drag on particles in steady, rectilinear motion which, although it is two-dimensional, gives results quite similar to those found in long, straight pipes. 

In Chaps, 10 and 11 we investigate two- and three-dimensional flows by using some of the ideas from this chapter and introducing several others. 

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