Investigation on Thermo-hydraulic Performance of Channel with Various Shapes of Rib Roughness: A Review

Abstract

To enhance the heat transfer performance, the advanced design of the equipment is essential as it can save energy, material, and cost. Among many techniques for the enhancement of the heat transfer rate, disturbance formation in the form of the roughness at the heated surface is suitable. This idea generally leads to generate turbulence. Ribs can highly be recommended for the placement on the heated surface to increase the heat transfer rate. The roughness in the form of ribs can be used in numerous applications such as solar air heater, gas turbine blade cooling, and nuclear reactors cooling, etc. Rough surface in the form of ribs create the disturbance in the laminar sub-layer. It leads to the increase in turbulence near the heated walls and this turned in to the enhancement of the heat transfer rate. However, rib roughness on the heated surface increases the flow resistance. So, this is the challenge to design a novel shape and configuration of ribs. The ribs should also be designed in the direction of enhancement of the heat transfer rate with the least pressure drop penalty. So, the objective of the article is to comprehend and explore the traditions behind the numerous design of ribs and their effect on the heat transfer rate. In recent years, a combination of more than one method to enhance the heat transfer are used simultaneously to achieve required heat transfer enhancement. The quest to enhance the heat transfer with a lesser drop in pressure by modification of heated surface is still a topic of research. So, there can be chances to enhance the heat transfer rate by using a novel design of ribs roughness. Lower heat transfer has been seen between the wall and the air because of the lower air heat transfer coefficient. Therefore, investigation on the heat transfer enhancement technique is still a research area when working fluid is air. It is also noticed that researchers have mainly used single shaped ribs, but combination of different shapes of ribs is not seen in the literature.