Transition to Turbulence in Accelerating Pipe Flow

Abstract

A uniformly accelerated laminar flow in a pipe, initially at rest, is analyzed. The acceleration increases the critical Reynolds number remarkably. New experimental findings are used to describe the transitional process in accelerating pipe flow. The results are shown to validate the previously suggested transition parameters obtained on the basis of results on small diameter pipes. The influence of the transition process on mean values is studied. The relationships between flow parameters and transition time were derived from the experimental results for data available. The time from the start of the flow to the initiation of turbulence can be predicted by an empirical formula.