Direct measurement of turbulent dissipation rate using dual laser doppler velocimeters

The analysis of two-point velocity correlation measurement, made in the anisotropic flowfield of axisymmetric sudden expansion using two-single component LDV systems, has been performed. Estimations of the Taylor microscale were made and the one dimensional energy spectrum was determined using the spatial and autocorrelation functions from these measurements. Difficulties in estimating the Taylor microscale from spatial and autocorrelations are discussed and methods to overcome these difficulties are suggested. Calculations of the one dimensional energy spectrum from curve fits to the correlation functions are explored and some hazards of the process are highlighted.