KOLMOGOROV LAW IN ANALYSIS OF THE TURBULENT SWIRL FLOW IN PIPE

Abstract

Here is discussed Kolmogorov’s law in the study of the turbulent swirl flow in pipe on the axial fan pressure side. This fan generates Rankine vortex where four zones are distinguished (vortex core region, shear stress region, sound flow region and boundary layer). In Figure 1 is presented spectral density of circumferential velocity fluctuations till frequency f = 200 Hz in the function of the frequency, i.e. ww Φ (f ) , obtained on the basis of the velocity field measured by use of the laser Doppler anemometry (LDA) [4]. Fan rotation speed is 1500 rpm which corresponds to the frequency f = 25 Hz. Achieved high Reynolds number, calculated on the basis of the average velocity Um = 4Q/(D2π), where Q is volume flow rate and D is pipe inner diameter, is Re = UmD/ν = 277018, where ν is kinematic viscosity. Here is applied one-component LDA system for measurements of three velocity components (axial U, radial V and circumferential W), subsequently.