On the effective temperature concept in the problem of laminar vortex shedding behind a heated circular cylinder
Journal
Physics of Fluids
Journal Volume
19
Journal Issue
5
Date Issued
2007
Author(s)
Abstract
Prediction of the nonisothermal vortex shedding based on the effective temperature Teff=T∞+c(TW−T∞) is always linked with the specific material properties of the working fluid, while a desirable universal prediction is unknown. Here we show that the thermal effect in diluted gases, where cylinder heating stabilizes wake flow (thus delaying the onset of vortex shedding), can be quantified in the extraordinary compact form of the proportionality between the critical Reynolds number ReC,∞ and the dimensionless film temperature Tf*. The theoretically derived c value for any dilute gas is related to an exponent n of the kinematic viscosity-temperature power law by a simple formula c=(2n)−1. The universal character of the proportionality has been proven; the linear increase of the critical Reynolds number is independent of the specific material properties for all diluted gases.
Publisher
American Institute of Physics Inc.
Type
journal article