REVIEW OF ENHANCEMENT TECHNIQUES WITH VAPOR EXTRACTION DURING FLOW BOILING IN MICROCHANNELS

Author(s)

Moreira, Debora C. ; Ribatski, Gherhardt ; Kandlikar, Satish G. ; Amer Soc Mech Engineers

• Document type: Journal article
• Source: PROCEEDINGS OF THE ASME 2020 18TH INTERNATIONAL CONFERENCE ON NANOCHANNELS, MICROCHANNELS, AND MINICHANNELS (ICNMM2020); v. N/A, p. 8-pg., 2020-01-01.

Abstract

Flow boiling heat fransfer in microchannels can remove high heat loads from restricted spaces with high heat fransfer coefficients and minimum temperature gradients. However, many works still report problems with instabilities, high pressure drop and early critical heat flux, which hinder its possible applications as thermal management solutions. Much comprehension on the phenomena concerning flow boiling heat transfer is still missing, therefore many investigations rely on empirical methods and parametric studies to develop novel configurations of more efficient heat sinks. Nevertheless, investigations involving vapor extraction have successfully addressed all these previously reported issues while also increasing the heat transfer of heat sinks employing flow boiling in microchannels. In this sense, the objective of this review is to identify the main techniques employed for vapor extraction in micro channels-based heat sinks and analyze the physical mechanisms underneath the observed improvements during flow boiling, such that some design guidelines can be drawn. Three main strategies can be identified: passive vapor extraction, active vapor extraction, and membrane-based vapor extraction. All these strategies were able to dissipate heat fluxes higher than 1 kW/cm(2), with the best performance achieved by a membrane-based heat sink, followed by active and passive designs. According to the present experimental and numerical data available in the literature, there is still room for improvement. (AU)

• FAPESP's process: 15/24834-3 - Development of high performance heat spreaders based on multi-microchannels with micro- and nanostructured surfaces aiming at applications in solar absorbers
• Grantee: Debora Carneiro Moreira
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 16/09509-1 - Phase change heat transfer processes of high performance applied to solar energy recovery
• Grantee: Gherhardt Ribatski
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 17/12576-5 - Design and experimental evaluation of microchannels-based thermal absorbers for solar collectors
• Grantee: Debora Carneiro Moreira
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor