THE EFFECTS OF CIRCULAR INSERTS ON THE THERMAL AND FLOW CHARACTERISTICS IN A HORIZONTAL PIPE EXCHANGER: A NUMERICAL INVESTIGATION

Abstract

The aim of the present study was to numerically investigate the effects of circular inserts placed inside a circular tube in order to evaluate the heat transfer characteristics under different operating conditions. Computational Fluid Dynamics methods were used to solve the model, which is a heat pipe with an outer diameter of 21 mm equipped with circular inserts with a distance of 20 cm. Different mass flow rates of the heat transfer fluid, including 25, 50, 75, 100, and 125 g/s were examined, and the thermal behavior of the turbulators and the flow structure were investigated. R19.0 version of ANSYS Fluent software was used as the CFD program to obtain the desired results and contours. From the results, it was found that circular inserts can be used in heat pipes to produce vortices and thus improve the heat transfer.

Keywords

• Vortex generator
• Turbulator
• Ring Pipe Inserts
• Numerical study
• ANSYS Fluent
• Turbulent flow
• Friction factor
• Heat Transfer

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