Journal of Applied Mechanical Engineering

Numerical prediction of the integral length scale of isotropic turbulence

Global Summit and Expo on Fluid Dynamics & Aerodynamics

August 15-16, 2016 London, UK

Kaifu Ye, Xin Liu and Jingwei Jiang

Naval Academy of Armament, Beijing, China

Scientific Tracks Abstracts: J Appl Mech Eng

Abstract:

As an important parameter of turbulence, the turbulence integral length scale has always been the hotspot of research. Nowadays, the turbulence integral length scale is obtained mostly by experiment. This paper proposed a numerical method: Compute unsteady flow field by LES, from which obtain fluctuation velocity and calculate the turbulence integral length scale based on velocity cross-correlation function. The three subgrid-scale models: DSL, WALE (wall-adapting local eddy viscosity model) and DKET, were analyzed in unsteady flow, time-average flow and turbulence integral length scale. The DSL turned out to have the highest precision. The DSL numerical method was used to predict the turbulence integral length scale of SUBOFF. The results showed that the peak bars of E are near 20 and 90 degree according to the existence of horse-shoe vortexes of conning tower and stabilizers; the integral lengths at outside radius were lager than those at inside radius because of the diffusion of vortexes. This research can provide a reference for further understanding of low-frequency broadband noise and the establishment of the numerical method of anisotropic turbulence integral length.

Biography :

Kaifu Ye has completed his Master’s in 1995. He is a famous Researcher in the Marine Engineering. He has published more than 15 papers in reputed journals and has been serving as an Editorial Board Member of repute.

Email: xiao43865@163.com