Abstract
Abstract This paper incorporates a study of the origin and dissipation of turbulence energy which makes possible a better understanding of the mechanics of energy losses that are introduced by various flow-disturbing devices such as expansions, bends, valves, etc. The important parameters which characterize turbulence are the root-mean-square values of the fluctuating velocity components, the length factor proportional to the size of the small eddies responsible for the dissipation of energy, and the length factor proportional to the average size of the eddies. The effect of variation of these parameters on the energy losses occurring in turbulent flow are discussed, and also the change in these parameters in the decaying turbulence beyond turbulence-producing devices is indicated. Data are presented showing the variation in the kinetic energy of mean flow and the turbulence energy in a 15-deg conical divergence. Visual studies of the start of turbulence at rounded entrances to smooth conduits seem to indicate that there is a regular vortex formation at the boundary, and the dispersion of these vortexes into the main fluid stream gradually establishes normal turbulent flow.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call