Finite Element Simulation for Heatline Visualization of Natural Convective Flow and Heat Transfer inside a Prismatic Enclosure

Abstract

Finite element simulation is performed visualizing heat flow through heatlines for a free convection flow and heat transfer in an air-filled prismatic enclosure. This configuration has applications in collecting solar energy in attic spaces of greenhouses and buildings having pitched roofs. The top inclined walls of the enclosure are considered at constant low temperature, two vertical walls are adiabatic whereas the bottom wall is heated isothermally as well as non-isothermally. The Galerkin weighted residual finite element method is used to solve the governing non-linear partial differential equations. The simulated results are displayed through streamlines, isotherms and heatlines to examine the effects of buoyancy on the flow and thermal fields. The Rayleigh number's effects on average temperature and velocity fields are also calculated and displayed graphically. The results indicate that for a uniformly heated bottom wall both the average temperature and the average velocity in the cavity are higher compared to the non-uniformly heated bottom wall. Furthermore, heatlines were observed to predict the energy transfer better than those of the isothermal lines.

Heatline Visualization for Thermal Transport in Complex Solid Domains with Discrete Heat Sources at the Bottom Wall

“…The understanding of thermal transport in complex geometries with discrete heat sources is of major importance. The applications include disposal of nuclear wastes, electronic circuits, geothermal areas, food processing industries and cooling of electronic components [1][2][3][4][5]. A thorough understanding of thermal transport in complex geometries with discrete heat source is essential in the design of above equipment.…”

“…It was found that the enhancement of heat transfer rate depended on the increment of solid wall thickness. Alam et al investigated the thermal transport in a prismatic cavity which is filled with air [5]. It was observed that the heatlines are normal to the isotherms in conduction dominant regime.…”

Heat and Mass Transfer and Entropy Generation Inside 3d Trapezoidal Solar Distiller

“…This convection is generated by buoyancy due to simultaneous temperature and concentration gradients. A sizable amount of research interests has been addressed on this subject (Mirabedin, 2016;Alam et al 2016;Bennacer et al 2001;Béghein et al 1992;Han et al 1992;Wee et al 1989;Chen et al 2011;Ghachem et al 2012;Tofaneli et al 2009;Costa, 2004). The outcome shows the occurrence of an oscillatory flow, provoked by the equilibrium between thermal and compositional forces, for a buoyancy number near the unity.…”

Study on numerical simulation of spirality inserted piece for heat exchanger

“…Figure 1 is the analyzed heat exchanger spoiler model, it is a further improvement on the basis of predecessors summarized. The improved spirality inserted piece manufacturing process is much easier, not only reduces the cost, improves the production efficiency, but also improves the heat transfer efficiency [6]. Since the large helical curved surface including the entire tube bundle, which is difficult to manufacture, is simplified into a spiral insert which can be easily manufactured and embedded in each tube.…”