Abstract
Present investigation, experimentally probes the influence of utilization of twisted tape turbulator inside a helical tube. Twisted tapes mix the flow and enhance the heat transfer rate. The pitch of twisted tape was considered as variant parameter. Tube was considered to be under constant heat flux. Also, Re number was within the range of 6000-32000 which denotes that flow was the turbulent flow regime. Various parameters including Nu number, friction factor and entropy generation were evaluated. Furthermore, performance evaluation criteria based on first law and second law of thermodynamics together with economic performance parameters were evaluated. The results revealed that by the increment of water flow rate and the decrement of twist pitch the Nu number would face a rise of 66% in comparison with the smooth helical tube. Also, it was found that the application of twisted tape has more effect on frictional entropy generation rather than thermal entropy generation. Finally, the results indicated that the maximum value of eta(c) was about 1.59 x 10(-7) ($/J) which presented up to 2.7 times enhancing in the financial beneficial of the helical tube.