Turbulence Length Scale Measurements by Two-Point Laser Doppler Anemometry in a Steady Flow

We propose here an experimental method, based on two-point Laser Doppler anemometry which makes possible direct measurement of spatial velocity correlation function from which the integral and Taylor's length scales are calculated. The technique has been carefully checked on simple flows and we present here a first application in a steady flow simulating the induction stroke of an internal combustion engine. Profiles of integral length scale, Taylor length scale and dissipation rate are determined at several distances from the cylinder head. The effect of valve lift is also taken into account.