Analysis of turbulence in entrance regime of rectangular duct using hot film anemometer

Abstract

Experimental analysis of turbulent flow properties associated with early entrance regime of rectangular duct flow is reported. Deterministic and statistical properties are measured across the width and depth of the rectangular duct at different locations along the duct. Measurements are carried out using hot film anemometer. Experiments are performed for Reynolds number in the range of 35000–115000. Turbulent time scale is obtained using autocorrelation function which leads to determination of integral and Kolmogorov length scale at various flow conditions. Variation of normalized centerline velocity (Ue/Ub) along the duct for different Reynolds number in the range mentioned above is analyzed. FFT analysis is carried out to detect the power content of flow and also to depict the chaotic nature of the flow.