Page 87 - Mechanical Engineers' Handbook (Volume 4)

76 Fluid Mechanics

Figure 30 Oblique shock relations, k 1.4.

wave angle is for weak shocks, generally with supersonic downstream flow at a Mach number
less than M .
1
Normal shock tables are used for oblique shocks if M is used for M sin . Then M
x 1 y
M sin(
) and other ratios of property values (pressure, temperature, and density) are
2
the same as for normal shocks.

11 VISCOUS FLUID FLOW IN DUCTS
The development of flow in the entrance of a pipe with the development of the boundary
layer is shown in Fig. 31. Wall shear stress is very large at the entrance, and generally
decreases in the flow direction to a constant value, as does the pressure gradient dp/dx. The

Figure 31 Growth of boundary layers in a pipe: (a) laminar flow; (b) turbulent flow.