Pressure and shear stress analysis in a normal triangular tube bundle based on experimental flow velocity field

Abstract

This paper presents the experimental vector velocity field obtained through the spatial filter velocimetry technique in a normal triangular tube bundle test section with tubes of 20 mm O.D. and transverse pitch of 25.2 mm. The experiments were conducted for water flows and Reynolds numbers ranging from 447 to 1842. The pressure field was estimated based on the velocity results by solving the Poisson equation. The shear stress around the tubes was analyzed calculating the viscous and Reynolds stresses. The results for turbulence strength and flow vorticity were calculated and discussed. All the analyses were performed using a second-order finite difference scheme to estimate the partial derivatives. The results indicate that the spatial filter velocimetry technique provides accurate velocity data and is suitable to be applied to complex geometries. In addition, the obtained velocity fields show that the SFV technique is capable of capturing asymmetric flow distributions, which switch from time to time, indicating a suitable spatial and temporal resolution for the experimental conditions evaluated in the present study.