A numerical study of the similarity of fully developed turbulent flows in orthogonally rotating square ducts and stationary curved square ducts

Abstract

A numerical study of a quantitative analogy of July, developed turbulent flow in a straight square duct rotating about an axis perpendicular to that of the duct and a stationary curved duct of square cross-section was carried out In order to compare the two flows, the dimensionless parameters K-TR = Re-1/4/rootRo and the Rossby number, Ro = w(m)/Omegad(h), in the rotating straight duct flow corresponded to K-TC = Re-1/4/rootlambda and the curvature ratio, lambda = R/d(h), in the stationary curved duct flow, so that they had the same dynamical meaning as those parameters for fully developed laminar flow. For the large values of Ro or lambda, the flow field satisfied the "asymptotic invariance property"; there were strong quantitative similarities between the two flows, such as in the flow patterns and fraction factors for the same values of K-TR and K-TC. Based on these similarities, it is possible to predict the flow characteristics in rotating ducts by considering the flow in stationary curved ducts, and vice versa.