Investigation of the hydrothermal phenomena in a wavy microchannel with secondary flow passages through mid-wall inflection points. (25th March 2023)

• Record Type: Journal Article
• Authors: Memon, Safi Ahmed; Akhtar, Shehnaz; Cheema, Taqi Ahmad; Park, Cheol Woo
• Is Part Of: Applied thermal engineering. Volume 223(2022)
• Publication Date: 2023-03-25
• Subjects: Wavy microchannels -- Secondary flow -- Flow disruption -- Thermal performance -- Temperature uniformity; Heat engineering -- Periodicals; Heating -- Equipment and supplies -- Periodicals; Periodicals; 621.40205
• DOI: 10.1016/j.applthermaleng.2023.120010
• Languages: English
• ISSNs: 1359-4311

Abstract

Highlights: A new structure of the torsional flow heat exchanger was presented. Periodic model was used in both the tube and shell side. Local heat transfer and flow resistance analysis at key positions was performed. The principle of enhanced heat transfer was analyzed according to the field synergy. The model reliability was verified experimentally. Abstract: Advancement in manufacturing processes has fuelled research in microchannel heat sinks to meet the demands of modern microelectronics. The heat sink design in the present study considers longitudinally wavy microchannels incorporating secondary flow passages. The secondary flow has been investigated for abrupt flow bifurcation (at 60° angle) and smooth flow bifurcation (at 30° angle). Further, these geometries were tested with different inlet–outlet configurations. The main objective of the paper is to study how a secondary flow would affect the flow profile and thermal performance of a wavy microchannel heat sink. The flow profile, pressure drop, temperature profiles, and average Nusselt number for a wide range of flow rates have been obtained and compared with those for the conventional design, and associated trends have been explored. Furthermore, the overall performance of the heat sink designs has been quantified by plotting the thermal enhancement factor (TEF) against a wide range of Reynolds numbers. The heat sink with flow bifurcation of 30° attains the highest value of Nuselt number below the flow rate of 1.8 × 10 -6 m 3 /s, whereas above this flow rate, the Nusselt number value of the conventional wavy heat sink dominates the proposed heat sink designs. The study corresponds to the demands of modern microchips such as the 13th Gen Intel® Core™ processor and serves as a guideline for manufacturing heat sinks with wavy microchannels incorporating secondary flow passages.