Abstract

Transition from laminar to turbulent flow in a pipe is one of the oldest and most fundamental problems in fluid mechanics. This phenomenon for time-dependent flows has been investigated by many researchers experimentally, analytically and numerically since the last century. However it is still an open research area for researchers. In most of the experimental studies conducted on transitional flow, the major topic is the relation between critical Reynolds Number, Re, and the amplitude of the disturbance field. The aim of this paper is to explain the turbulence transition in time-dependent pipe flows, summarizing the numerical, analytical and experimental study topics pointing out the gaps to be fulfilled in future.