Investigating the Effect of Angle and Length of Vortex Generators with Sinusoidal Structure on Compact Heat Exchangers Performance

Document Type : Original Article

Authors

Ali Sadollah ¹

Davood Barati ²

Amir Hossein Dodangeh ³

¹ Department of Mechanical Engineering, Faculty of Engineering, University of Science and Culture, Tehran, Iran

² Department of Mechanical Engineering, Islamic Azad University, Central Tehran Branch, Tehran, Iran

³ Department of Mechatronics, Islamic Azad University, Karaj Branch, Alborz, Iran

10.22067/jacsm.2024.81445.1171

Abstract

The increasing use of compact heat exchangers, which both have less weight and occupy a smaller space than large exchangers, has made the study of such exchangers more necessary. In this article, the aim is to examine several proposed models of this type of converters with the presence of vortex generators in different geometries, in terms of heat transfer rate and pressure drop. To achieve these goals, vortex generators with sine wave regulation have been designed and investigated under several angles of attack and different lengths to determine the effects of these different geometric parameters on the heat transfer rate from the tubes. and determine the pressure drop along the converter. In the given problem, hot air with a constant temperature of 350 K is flowing inside the tubes and cold air with a temperature of 300 K is flowing in the shell of the heat exchanger. This problem has been discretized in a steady state and in a two-dimensional form in a slow fluid flow (Reynolds numbers between 400 and 1000), using the finite element method, and analyzed in the Ansys Fluent commercial software. Finally, sinusoidal vortex generators with an angle of attack of 20 degrees and a length of 6 mm have the most appropriate amount of heat transfer and pressure drop among the studied conditions.

Keywords

Heat transfer rate

Compact heat exchanger

Sinusoidal vortex generators

London goodness factor

Subjects

• Heat transfer

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