Numerical Investigation of Heat Transfer in a Rectangular Channel with Square Baffles and a Triangular Obstacle

Abstract

In this work, the heat transfer was investigated in a rectangular channel with an internal triangular obstacle and square baffles. Three square baffles were located on the lower wall of the channel, while a triangular obstacle was placed in the middle of the channel and placed before the first baffle. Air was used as a working fluid. The governing equations were solved with finite volume method. The effect of the geometric parameters such as the ratio of the width to height of the obstacle, the vertical and horizontal distance between obstacle and baffle and the baffle angle, has been investigated on the heat transfer in this system. Then, in next parts, the effect of baffle and obstacle shape was considered. The results show that by increasing the width and height of the obstacle, the baffle temperature decreases and the Nusselt number of the baffle increases. In fact, when the obstacle width becomes larger, a longer vortex is formed that helps to improve the heat transfer rate. Also, when the obstacle is perpendicular to the flow path, better heat exchange between the baffle and the fluid was performed. With Elliptical baffles and a triangular obstacle, higher heat transfer was achieved.