Evaluation of high-order concentration statistics in a dispersing plume

Abstract In this paper we analyze the concentration higher-order moments of a dispersing plume in a neutral wind tunnel boundary layer. They are evaluated through a fluctuating plume model in which the plume barycenter is directly calculated from the measured mean concentration field. The reliability of the model is firstly verified by comparing the simulated and measured moments up to the fourth order. Then the relationships between higher and lower-order moments are investigated seeking for a proper scaling of the fourth, fifth and sixth-order normalized moments. We found that a general behavior appears when they are expressed as a function of the third-order moments. In this case each order calculated or measured at different distances collapses on the same curve.