Parametric investigation of the effect on heat transfer of triangular obstacle arrays in a channel

Heat transfer in a channel in presence of a set of triangular prism has been investigated experimentally and numerically in turbulent flow regime. The square cross-sectional channel is used and the triangular prisms are located in the middle of the channel. The bottom wall of the channel is heated with constant heat flux. The channel aspect ratio and triangular prism elements dimensions are considered fixed. Three equilateral triangular prism elements have been used with four different attack angles in cross flow of air. The heated surface temperatures and bulk temperatures are measurement by using thermocouples on the experimental setup. The Nusselt number was calculated for heat transfer rate. Based on the experimental data a numerical study is performed. The computational procedure is based on the finite volume technique and the standard k–ε formulation was chosen for turbulence closure. Results are presented in the form of streamline and temperature contour plots around the circumference of the cylinder. The flow characteristics are analyzed in the forms of streamlines and pressure fields at various Reynolds numbers. The set of triangular prism is effected flow field and changed heat transfer rate from heated surface. Diagram of Nusselt number versus Reynolds numbers is presented and discussed. Results are compared with the available data in the literature that display good agreements. It has been observed that placing triangular prism obstacles in the channel shows a significant increase in heat transfer. Keywords: Heat transfer enhancement, Convection, Triangular prism, Cross-flow. October, 2020; 86 pages