When a valve is closed suddenly in a pipe with flowing water, a water hammer pressure wave is set up. The very high pressures generated by such waves can damage the pipe. The maximum pressure, pmax, generated by water hammer is a function of liquid density, ρ, initial flow speed, U0, and liquid bulk modulus, Eυ. How many dimensionless groups are needed to characterize water hammer? Determine the functional relationship among the variables in terms of the necessary Π groups.
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