A theoretical approach to be applied in heat exchangers by using the thermal efficiency concept and the second law of thermodynamic

Élcio Nogueira

doi:10.59400/mea.v1i1.92

A theoretical approach to be applied in heat exchangers by using the thermal efficiency concept and the second law of thermodynamic

Élcio Nogueira Universidade do Estado do Rio de Janeiro–DME/FAT/UERJ, Resende 27537-000, Brazil

Article ID: 92

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DOI: https://doi.org/10.59400/mea.v1i1.92

Keywords: thermal efficiency concept, second law of thermodynamics, Bejan number, heat exchangers

Abstract

A review of the concepts of thermal efficiency and thermal and hydraulic irreversibilities is presented, applying the second law of thermodynamics and thermodynamic Bejan number. An example problem, typical of thermal heat exchange between two fluids, is given, with a dimensionless solution for parallel and counterflow flows. The quantities of interest presented through the example are thermal efficiency, thermal effectiveness, thermal irreversibility, the relationship between outlet and inlet temperatures versus the number of thermal units, and outlet temperature for hot fluid. The theory presented in this review has been applied to numerous problems related to heat exchangers over the last three years, as per references.

References

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[5]Nogueira É. Efficiency and effectiveness thermal analysis of the shell and helical coil tube heat exchanger used in an Aqueous Solution of Ammonium Nitrate Solubility (ANSOL) with 20% H2O and 80% AN. Journal of Materials Science and Chemical Engineering 2021; 9(6): 24–45. doi: 10.4236/msce.2021.96003

[6]Nogueira É. Thermodynamic performance of boehmite alumina nanoparticle shapes in the counterflow double pipe heat exchanger. Journal of Engineering Sciences 2022; 9(1): F1–F10. doi: 10.21272/jes.2022.9(1).f1

[7]Nogueira É. Efficacy of the number of plates, fluid flow rate and volume fractions of aluminum oxide nanoparticles on thermal performance of gasket plate heat exchanger. International Journal of Engineering Research Updates 2022; 2(1): 25–38. doi: 10.53430/ijeru.2022.2.1.0027

[8]Nogueira É. Efficiency and effectiveness method versus ε-NTU method with application in finned flat tube compact heat exchanger with water-ethylene Glycol as nanofluid base of iron oxide nanoparticles. Journal of Materials Science and Chemical Engineering 2022; 10: 1–17. doi: 10.4236/msce.2022.102001

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[13]Nogueira É. The effectiveness method (ε-NTU) to analyze the thermal performance of the flat tube multi-louvered finned radiator with silver nanoparticles suspension in ethylene Glycol. International Journal of Advanced Technology and Engineering Exploration 2020; 7(66). doi: 10.19101/IJATEE.2020.762040

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Published

2023-08-21

How to Cite

Nogueira, Élcio. (2023). A theoretical approach to be applied in heat exchangers by using the thermal efficiency concept and the second law of thermodynamic. Mechanical Engineering Advances, 1(1), 92. https://doi.org/10.59400/mea.v1i1.92

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Issue

Vol. 1 No. 1 (2023)

Section

Review

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

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