Pressure and Velocity Distributions in Pulsating Turbulent Pipe Flow Part 1 Theoretical Treatments

抄録

Fundamental equations for pulsating turbulent flow in a circular tube containing a slightly compressible fluid are derived by describing Reynolds stress in terms of eddy viscosity, for whose distribution five models are introduced. Analytical solutions based on each model are developed for steady flow velocity, oscillating velocity and wave propagation constant. Comparison of these solutions for each model shows that the four-region model proposed by Karman is rather reasonable enough to illustrate the flow behaviours. The distributions of oscillating velocities, wave propagation constant, and oscillating pressures based on the four-region model at low frequencies and small Reynolds numbers are similar to those at high frequencies and small Reynolds numbers are similar to those at high frequencies and large Reynolds numbers. Because of the assumption of time-invariant eddy viscosity profile, the low frequency values of wave propagation constant should not be reliable. The analogy of these turbulent flow solutions with the laminar ones is shown schematically.