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Keywords

Corrugated Tubes
Four-Starts
Severity Index
Heat transfer enhancement
Friction factor

Abstract

This article dealt with an important heat transfer field, which is passive heat transfer technique represented by corrugated tube. The study conducted numerically by ANSYS Fluent 14. The motivation behind the current study was to clarify the characteristics and merits of such tube geometry in terms of heat transfer and pressure drop. The obtained results reported under constant heat flux, temperature-dependent thermo-physical properties and Reynolds number range of 300-1500. Results show good heat transfer enhancement of 6.15-33.24% in spite of an increase in friction factor of 1.80-2.93 times the smooth values. The corrugated tube with φ =4.76×10-2 has the top thermal 1.16-1.25 for all Reynolds number. The most important finding is that the gained heat transfer is much more than the increase in pressure loss until a certain threshold of Reynolds number about 900, later, the pressure loss increase and dominates over the heat gained. The effect of Prandtl number on the heat transfer for three types of fluids produced too. A criterion correlation equation of Nusselt number developed to describe the cases of four starts spirally corrugated tubes by deviation ±3% compared with the simulation results.
https://doi.org/10.30772/qjes.v10i4.493
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