Is the Critical Reynolds Number Universal?

Abstract

The laminar-turbulent transition in the circular pipe flow has been tested experimentally. The critical Reynolds numbers for the flows of different gases (He, Ne, Ar, Kr, Xe, N2, CO2, SF6) and liquids (H2O, D2O, C2H5OH) have been compared. The difference up to 40% was observed. The possible reasons of non-universality of critical Reynolds number are discussed. The conclusion is the statistical approach is needed to penetrate into the nature of observed phenomenon.