Reynolds Time-Averaging Concept in Turbulent Flow

The fundamental difference between laminar and turbulent flow is the chaotic and random behavior of flow properties such as velocity, pressure, shear stress, temperature etc. One way to handle such high Reynolds number flow is to standardize in terms of mean/average value of flow parameters. Such a technique is known as “Reynolds Time-Averaging Concept”. In this method, the flow parameters are expressed in terms of two quantities; one is the time-average value and the other is the fluctuating part with respect to average value.

Fig. 2: Time averaging concept in turbulent flows.