Noncircular conduits laminar flow

Table 7-1 Laminar Flow Factors for Noncircular Conduits...

Values of h for turbulent or laminar flow through a conduit with a noncircular cross section can also be predicted by either Equation 5.8a or 5.9a, respectively, by using the equivalent diameter d, as defined by the following equation, in place of d,. 

For laminar flows, the laminar sublayer fills the entire cross section. Thus, the effect of wall drag is influenced to a greater extent by the shape of the cross section. For many noncircular conduits with laminar flows, either theoretical analyses (similar to the Hagen-Poiseuille equation) or numerical analyses for the pressure-flow relation have been conducted. The results can be expressed in dimensionless form as... 

It will be our purpose in this chapter to develop those techniques that are needed to determine F/,. We will consider both laminar and turbulent flows, conduits with circular and noncircular cross sections, complex piping situations, expansions, and contractions. The overall result will be the ability to handle effectively many of the situations that can and do confront the engineering practitioner. 

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