Comparison of length scale estimates for a sudden expansion flow estimated from spatial and auto correlation LDV measurements

Abstract

Two-point velocity correlation measurements were made in the anisotropic flow field of an axisymmetric sudden expansion using two single component LDV systems. The integral length scales and Taylor microscales were estimated and compared with those obtained from auto correlation measurements in conjunction with Taylor's hypothesis. The agreement of the integral scales was within 20% and the values scale well with the flow geometry, while the agreement of the microscales was within 43%.