Impact of moving arc-shaped segment and optimized splitter on the convective-radiative heat transfer in an inverted T-shaped cavity

The purpose of this study is to maximize the utilization of a heat sink by optimizing the fluid circulating inside an enclosure undergoing convective and radiative heat transfer. Two mechanisms; moving arc-shaped surface and optimally fluid guiding towards the active walls do the fluid circulation. The two mechanisms of enhancing convective-radiative heat transfer inside an inverted T-shaped enclosure are achieved by rotating a contact cylinder to form an arc-shaped moving surface and inserting an adiabatic thin splitter to guide the fluid towards the heat hot wall. The computations are performed numerically using Galerkin FEM for a symmetric one-half of the physical domain. The splitter's position is optimally estimated using the Nelder-Mead optimization algorithm. The outcomes show that the clockwise movement of the arc-shaped segment guides the fluid to be consistent with the lifted buoyancy force, making it 50% more effective than the counterclockwise direction, which leads to opposite vortices. The splitter provides a 19% gain in convective heat transfer. Its optimum position is given for each Reynolds number, where, with a higher Reynolds number, the splitter should be displaced from the enclosure's centerline and the arc-shaped rotating surface. The radiation parameter, which varies from 0 to 5, plays a similar role to the Reynolds number, proportionally augmenting the overall heat transfer. The study presents a new coupling of two mechanisms, arc-shaped moving wall and a locally optimized divider to circulate the heat transfer fluid in a novel inverted T-shaped cavity.