Heat Transfer Enhancement in Circular Tube using Twisted Tape Inserts of Different Width Ratio under Constant Wall Heat flux Condition

Abstract

The present study reports an experimental analysis on heat transfer, friction factor and thermal performance characteristics of turbulent flow (7500 ≤ Re ≥ 13,000) in heat exchanger tubes with twisted tape as swirl generators under constant wall heat flux condition. The experiments were carried out for twisted tape inserts at five different width ratios (W/D) of 0.35, 0.44, 0.53, 0.62 and 0.71 at constant twist ratio (H/D) of 2.5. The experimental results show that Nusselt number increases with increasing Reynolds number and increasing width ratio (W/D) of the swirl generators. Also the friction factor decreases with increasing Reynolds number and decreasing width ratio. Nusselt number increased in ranges of 6.04% to 17.26% compared to the results of the tube without twisted tape (the plain tube), depending on the operating conditions. At the same pumping power, the use of twisted tape inserts results in thermal performance factor up to 1.17 times of those of the plain tube. In addition, the correlations that developed from the present experimental data for Nusselt number.

Number of Tape Twists Effects on Solar Water Heater Performance

“…The finite volume method with tetrahedral elements was selected discrete the domains, as shown in the Fig. (4). A standard k -epsilon model was used to solve these cases.…”

“…Tikhe et. al [4] studied experimentally the heat transfer, friction factor, and thermal performance of heat exchanger tubes with twisted tapes as swirl generators at turbulent flow with (7500 ≥ Re ≤ 13000) under constant wall heat flex condition. Five different width ratios at a constant twist ration were approved.…”

Heat Transfer Enhancement for Tube in Tube Heat Exchanger Using Twisted Tape Inserts

“…It was derived that the values of Nusselt number, Reynolds number, Prandtl number, pressure drop and friction factor are dependent on the geometries of the twisted tape with different twist ratio, pitch ratio, tape width etc. Prashant Tikhe et.al [5] have investigated the heat transfer enhancement using twisted tape inserts of different width ratio and under constant wall heat flux condition. The experiments were carried out to determine heat transfer, friction factor and thermal performance characteristics in turbulent flow (7500 < Re < 13000).…”

Review on Recent Progresses in Heat Transfer Enhancement Through the Use of Passive Vortex Generators and Its Applications in Solar Parabolic Trough Systems

“…K. Sivakumar [38] carried out similar experiments and observed that when applied with uniform heat flux with twisted tape inserts in circular tube correlation can be established between Reynolds number and outlet temperature of the pipe. Prashant Tikhe [39] carried out experiments in circular tubes with uniform heat flux and water as heat transfer fluid and observed that with increasing the ratio of width to diameter in range of 0.35 to 0.71 at constant twist ratio of 2.5 thermal efficiency gets increased.…”