Hydrodynamic and thermal characteristics of single and two-phase flow in micro pin fin heat sinks

• Grant number: 19/02566-8
• Support type: Regular Research Grants
• Duration: May 01, 2019 - April 30, 2022
• Field of knowledge: Engineering - Mechanical Engineering - Transport Phenomena
• Principal researcher: Elaine Maria Cardoso
• Grantee: Elaine Maria Cardoso
• Home Institution: Faculdade de Engenharia (FEIS). Universidade Estadual Paulista (UNESP). Campus de Ilha Solteira. Ilha Solteira , SP, Brazil
• Assoc. researchers: Alessandro Roger Rodrigues

Abstract

The growing demand for high-capacity heat-removal devices of smaller dimensions has required the scientific community to research solutions such as the use of microchannel-based heat sinks. These turned out to be an efficient solution as they reduced the amount of material and coolant used and could be designed in the dimensions of chips. By combining the geometry of the microchannels with saturated boiling of the refrigerant, it was possible to achieve dissipated heat fluxes in the order of 10 MW/m². However, the use of rectangular microchannels in convective boiling soon encountered some technical difficulties, such as the reverse flow of the fluid and thermal instabilities in the heat exchanger. Thus, new configurations of microchannels have been researched, among them the use of segmented microchannels or micro-pin fins. Micro-pin fin heat sinks have high thermal exchange efficiency due to the increase of the effective area of contact with the refrigerant, maintaining the advantages of applying the microchannels, but reducing the effect of instabilities. The present project aims to evaluate experimentally and analytically the thermal and hydrodynamic performance of a micro-pin fin heat sink by using HFE-7100 fluid (working fluid with low ozone depletion potential and low global warming potential). In the experimental part, the square-micro pillar arrays will be etched on a plain copper surface through micro-milling process by using CNC precision machining. Squares micro-fins of different length scales (i.e., height, diameter, and inter-fin space) were uniformly spaced on the plain copper surface. Two arrangements of heat sinks will be tested: one with orthogonal inlet to the direction of fluid flow, and another with inlet forming an angle of 45 ° to the flow direction. Experimental data for the heat transfer coefficient and pressure drop will be obtained under conditions of saturated two-phase flow, varying the applied heat flux and the mass velocity. The experimental data obtained, together with data from other authors, will be used to perform an analytical study on prediction methods present in the literature, in order to verify their reliability in the prediction of heat transfer coefficient (CTC) and pressure drop for microheat sinks. (AU)

Scientific publications

(8)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

DOS SANTOS FILHO, ERIVELTO; KIYOMURA, IGOR SEICHO; DE ANDRADE, BRUNO ALVES; CARDOSO, ELAINE MARIA. Pool boiling performance of HFE-7100 on hierarchically structured surfaces. CASE STUDIES IN THERMAL ENGINEERING, v. 28, DEC 2021. Web of Science Citations: 0.

GAJGHATE, SAMEER SHESHRAO; BARATHULA, SREERAM; CARDOSO, ELAINE MARIA; SAHA, BIDYUT BARAN; BHAUMIK, SWAPAN. Effect of staggered V-shaped and rectangular grooves copper surfaces on pool boiling heat transfer enhancement using ZrO2 nanofluids. Journal of the Brazilian Society of Mechanical Sciences and Engineering, v. 43, n. 2 JAN 22 2021. Web of Science Citations: 0.

GOODARZI, MARJAN; TLILI, ISKANDER; MORIA, HAZIM; CARDOSO, E. M.; ALKANHAL, TAWFEEQ ABDULLAH; ANQI, ALI E.; SAFAEI, MOHAMMAD REZA. Boiling flow of graphene nanoplatelets nano-suspension on a small copper disk. Powder Technology, v. 377, p. 10-19, JAN 2 2021. Web of Science Citations: 7.

DA CUNHA, ALEX P.; MOGAJI, TAYE S.; DE SOUZA, REINALDO R.; CARDOSO, ELAINE M. A Method for Measuring Contact Angle and the Influence of Surface-Fluid Parameters on the Boiling Heat Transfer Performance. JOURNAL OF HEAT TRANSFER-TRANSACTIONS OF THE ASME, v. 142, n. 9 SEP 1 2020. Web of Science Citations: 0.

KIYOMURA, IGOR SEICHO; NUNES, JESSICA MARTHA; DE SOUZA, REINALDO RODRIGUES; GAJGHATE, SAMEER S.; BHAUMIK, SWAPAN; CARDOSO, ELAINE MARIA. Effect of microfin surfaces on boiling heat transfer using HFE-7100 as working fluid. Journal of the Brazilian Society of Mechanical Sciences and Engineering, v. 42, n. 7 JUN 11 2020. Web of Science Citations: 0.

MANETTI, LEONARDO LACHI; RIBATSKI, GHERHARDT; DE SOUZA, REINALDO RODRIGUES; CARDOSO, ELAINE MARIA. Pool boiling heat transfer of HFE-7100 on metal foams. EXPERIMENTAL THERMAL AND FLUID SCIENCE, v. 113, MAY 1 2020. Web of Science Citations: 0.

MANETTI, LEONARDO LACHI; OLIVEIRA HENRIQUES MOITA, ANA SOFIA; DE SOUZA, REINALDO RODRIGUES; CARDOSO, ELAINE MARIA. Effect of copper foam thickness on pool boiling heat transfer of HFE-7100. INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER, v. 152, MAY 2020. Web of Science Citations: 0.

NUNES, JESSICA MARTHA; SOUZA, REINALDO RODRIGUES DE; RODRIGUES, ALESSANDRO ROGER; SAFAEI, MOHAMMAD REZA; CARDOSO, ELAINE MARIA. Influence of coated surfaces and gap size on boiling heat transfer of deionized water. Journal of the Brazilian Society of Mechanical Sciences and Engineering, v. 42, n. 3 FEB 15 2020. Web of Science Citations: 0.