Eventos Anais de eventos
ENCIT 2022
19th Brazilian Congress of Thermal Sciences and Engineering
NUMERICAL EVALUATION OF THE APPLICATION OF MWCNT NANOFLUIDS IN AUTOMOTIVE FLAT TUBE RADIATORS
Submission Author:
Erick Oliveira do Nascimento , PA
Co-Authors:
Erick Oliveira do Nascimento, Edwin Martin Cardenas Contreras, ENIO PEDONE BANDARRA FILHO
Presenter: Erick Oliveira do Nascimento
doi://10.26678/ABCM.ENCIT2022.CIT22-0217
Abstract
Heat dissipation and high performance cooling are some of the most important needs in the industry and are closely linked to the energy efficiency of cooling systems. In the automotive industry, engines need radiators with a highly efficient cooling system, in addition to having lower fuel consumption and emission of harmful gases to the environment. In this work, a numerical study was carried out to evaluate the application of MWCNT nanofluids in a flat tube automotive radiator. The influence of the Reynolds number and the concentration of nanoparticles in a flat tube under the action of a constant convective air flow of 50 W/(m2 ·K) in a laminar regime was investigated. It is also noteworthy that in this work the thermophysical properties (thermal conductivity, specific heat, density and dynamic viscosity) of the analyzed fluids are considered temperature dependent along the flow implemented by a user-defined function (UDF). The governing equations (continuity, momentum and energy) were solved using the finite volume method implemented in the Ansys Fluent program with the SIMPLE pressure-velocity coupling method. Numerical convergence was given when the residual of the equations of continuity and momentum were less than 10−6 and energy less than 10−9. For nanofluids with nanoparticles concentration of 0.05, 0.1 and 0.2 vol.%, simulation was performed for the Reynolds numbers of 250, 750 and 1500 at an inlet temperature of 353.15 K From the results obtained, it was observed that the insertion of nanoparticles and the increase in the Reynolds number, increases the average heat transfer rate by up to 15.05 % and 80.70%, respectively, in relation to to the base fluid. Despite the increases in the convective heat transfer coefficient for all concentrations, the Nusselt number showed a decrease of up to 5.40 % with the insertion of nanoparticles. Therefore, the analyzed MWCNT nanofluids showed promising thermal performances for applications in automotive radiators.
Keywords
Heat transfer, Nanofluids, Automotive radiator, Computational fluid dynamics (CFD)
