THE REFLECTION OF WAVES OF FINITE-AMPLITUDE AT AN OPEN EXHAUST

Wave reflection at an open pipe termination discharging to atmosphere is of practical interest in the environmental assessment of prime movers, of power generating installations or construction plant, etc. When the fluctuating pressure amplitude in the pipe remains sufficiently small, so that waves propagate without change in their shape, the acoustic approximations provide valid descriptions of the wave motion, either in frequency or in time. Fluid velocities and pressure fluctuations associated with the wave can be represented by the linear sum of the fluctuations associated with a pair of incident and reflected component waves. More complicated flows are discussed, and pertinent experiments are reported.