Kyoto University · Engineering
Professor Xiuzhong Shen's research lab specializes in experimental fluid dynamics, with a primary focus on turbulence in shear flows and grid-generated turbulence. The lab investigates the statistical properties of velocity fluctuations, structure functions, and the validity of fundamental turbulence hypotheses such as local isotropy at high Reynolds numbers. Using advanced wind tunnel facilities with active grids and shear generators, the lab explores scaling laws, intermittency, and the transition to fully developed turbulence across a wide range of Reynolds numbers. Their work bridges theoretical predictions with high-precision experimental data in both uniform shear and decaying (shearless) turbulent flows.
Figures are computed from collected data and may differ slightly.
The postulate of local isotropy (PLI) is tested in a wind tunnel uniform shear flow in which the Reynolds number is varied over the range 100⩽Rλ⩽1, 100(6.7×102⩽Rl⩽6.3×104). The high Rλ is achieved by using an active grid [Mydlarski and Warhaft, J. Fluid Mech. 320, 331 (1996)] in conjunction with a shear generator. We focus on the increments of the longitudinal velocity fluctuations in the direction of the mean shear. PLI requires that odd order moments of these quantities approach zero as Rλ→∞.
The scaling exponents of the longitudinal structure function, 〈Δuxn〉 and two different transverse structure functions: the longitudinal velocity, u, measured in the transverse, y direction (the direction of the mean shear), 〈Δuyn〉, and the transverse velocity v, measured in the flow direction, x, 〈Δvxn〉, up to n=8, are studied in an approximately uniform shear flow [Shen and Warhaft, Phys. Fluids 12, 2976 (2000)], as well as in decaying (shearless) grid turbulence. Results, for low Reynolds numb
Open papers in the app to read, cite, and organize with AI.
