Natural Convection in a Vertical Enclosure With Grooves

Abstract

The natural convection in a vertical enclosure with grooves has been numerically studied. To identify the structure of the thermal boundary layer along the discontinuous vertical surface, the iso-flux condition is imposed to each heating (or cooling) portion of the discontinuous vertical surface, and the adiabatic condition is applied to the other solid walls including the grooves. We focus on the behavior of the thermal boundary layer along the discontinuous vertical surface, and clarify the dual structure of the thermal boundary layer. The whole thermal boundary layer develops along the discontinuous vertical surface, while the internal thermal boundary layer forms on each solid portion of the discontinuous flat surface. We can recognize from the isotherms near the solid portion that the internal thermal boundary layer develops from the leading edge to the trailing edge of the solid portion. The internal thermal boundary layer plays an important role in the heat transfer enhancement. As the thin thermal boundary layer forms at the leading and trailing edges, the heat transfer coefficient near the leading and trailing edges takes higher values.