Thermal performance of a hollow cylinder with low conductive materials in a lid-driven square cavity with partially cooled vertical wall

Abstract

• A hollow cylinder is used to study the thermal performance of different low conductivity materials. • A square chamber is defined as one with a moving top wall and a partly cooled left vertical wall. • Within the lid-driven chamber, a hot hollow cylinder is positioned, which acts as a heat source. • The numerical investigation is obtained by changing the thermal conductivity (K) of the cylinder's solid objects. • The heat absorption rate of all materials decreases significantly over time. Extensive research has focused on mixed convection in a lid-driven cavity. However, the thermal characteristics of a hollow cylinder made of low-conducting materials such as wood, high-density plastic, bricks, and concrete are not explored, even though they have a lot of real-world applications in engineering and technology. Thus the thermal performance of a hollow cylinder with several low conductive materials such as wood, high-density plastic, bricks, and concrete is investigated in this study. A square enclosure with a moving lid and partially cooled right vertical wall is considered. A heated hollow cylinder is placed in the center of the enclosure as a heat source. A set of governing equations with the appropriate initial and boundary conditions of this model is solved using finite element approach based on Galerkin weighted residual method. The numerical study is performed by varying the thermal conductivity ( K ) of the cylinder’s materials with transient conditions, and outcomes are depicted in terms of streamlines, isotherms, and different thermo-hydrodynamic properties such as average shear rate, drag force, average rate of heat transfer and heat absorption rate. The results indicated that the heat transfer rate of wood is initially greatest at the top but gradually decreases to the rock-bottom. Furthermore, the heat absorption rate of all materials decreases significantly over time; on average, wood absorbs 31% more heat than concrete.