Theoretical analysis using thermal efficiency concept in straight micro channel printed circuit heat exchanger

Élcio Nogueira; Humberto Araújo Machado

doi:10.59400/mea.v1i1.66

Theoretical analysis using thermal efficiency concept in straight micro channel printed circuit heat exchanger

Élcio Nogueira Faculdade de Tecnologia–FAT/UERJ, Resende 27537-000, Brazil
Humberto Araújo Machado Instituto de Aeronáutica e Espaço–IAE, São José dos Campos 12228-904, Brazil

Article ID: 66

6293 Views, 6176 PDF Downloads

DOI: https://doi.org/10.59400/mea.v1i1.66

Keywords: printed circuit heat exchanger (PCHE); microchannels; thermal efficiency; second law of thermodynamics; dimensionless theoretical analysis; non-spherical nanoparticles

Abstract

The objective is to analyze the thermal and hydraulic performance in a micro channel straight printed circuit heat exchanger. Counterflow and parallel flow configurations were analyzed for water cooling using ethylene glycol-based fluid and platelet-shaped, non-spherical Boehmite alumina nanoparticles. The work presents results from applying a dimensionless theory that uses the concepts of thermal efficiency of heat exchangers and quantities associated with the second law of thermodynamics. Thermal efficiency, thermal effectiveness, thermal and viscous irreversibilities, thermodynamic Bejan number, and outlet water temperatures are presented in graph form. The data obtained allow us to conclude that the heat exchanger can work in a range of water and refrigerant flow rates below the design parameters. With the inclusion of nanoparticles with a volume fraction equal to 5.0%, the flow rates of the refrigerant fluid can be significantly reduced. The analysis performed shows that the use of nanoparticles improves the operational cost-benefit of the heat exchanger with a significant reduction in the hot water outlet temperature.

References

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Published

2023-08-21

How to Cite

Nogueira, Élcio, & Machado, H. A. (2023). Theoretical analysis using thermal efficiency concept in straight micro channel printed circuit heat exchanger. Mechanical Engineering Advances, 1(1), 66. https://doi.org/10.59400/mea.v1i1.66

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Issue

Vol. 1 No. 1 (2023)

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Article

This work is licensed under a Creative Commons Attribution 4.0 International License.

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