International Journal of Recent Technology and Engineering (IJRTE) ISSN: 2277-3878, Volume-8 Issue-3, September 2019 1708 Published By: Blue Eyes Intelligence Engineering & Sciences Publication Retrieval Number: C4452098319/19©BEIESP DOI:10.35940/ijrte.C4452.098319 Abstract: The paper presents computational fluid dynamics study of non-conventional insert vortex generator using Commercial software, to analyze the effect of vortex generator insert on heat transfer augmentation and fluid flow behavior. The study was done for Reynolds number 10000, 15000, 25000, 35000 and 45000 with working fluid as air flowing through a tube with a constant heat flux of 1000 w/m2. Current study validates the experimental results from the literature study. The heat transfer of these inserts with various geometrical arrangements viz. pitch to projected length ratio, angle of attack and height to inner diameter ratio are investigated here with the help of computational fluid dynamics software. The physical mechanism of formation and development of vortex flow from the leading edge to trailing edge of the insert is studied and it is observed that Nusselt number increases as an increment in Reynolds number. The ratio of augmented Nusselt number to smooth tube Nusselt number is found to be decreasing with increase in Reynolds number. Index Terms: Ansys Fluent, Computational Fluid Dynamics, Heat Transfer Enhancement, Vortex Generator Insert. I. INTRODUCTION The heat transfer characteristics of any heat exchanger can be enhanced by certain techniques that are active techniques and passive techniques. In active technique, help of some external power supplying unit is taken and the passive technique involves heat transfer enhancement without external power supplying unit. The passive technique uses various types of inserts which are reported in the literature survey. Deshmukh et al. [1] studied the use of delta wing vortex generator as an insert in a tube. In this study effect of vortex generator on heat transfer performance is analyzed. They have studied thermohydraulic characteristics of vortex generator for various geometrical parameters viz. height to inner tube diameter ratio, pitch to projected length ratio (p/pl) and angle of attack. The working fluid is used as air. The ratio of Nusselt number (Nua/Nus) with insert and without insert is found to be ranging from 1.3 to 5.0. Promvonge et al. [2] studied conical-shaped ring turbulator insert and their effects on heat transfer and friction factor are analyzed. The result of experiment shows that Revised Manuscript Received on September 15, 2019 * Shrinivas C. Deshmukh, School of Mechanical and Civil Engineering, MIT Academy of Engineering Alandi (D), Savitribai Phule Pune University, Pune, India, 412105. Email: scdeshmukh@mitaoe.ac.in Dr. Prashant W. Deshmukh, Department of Mechanical Engineering, College of Engineering, Pune, India. 411005. Email: pwdeshmukh25@gmail.com Prafulla R. Hatte, School of Mechanical and Civil Engineering, MIT Academy of Engineering Alandi (D), Savitribai Phule Pune University, Pune, India. 412105. Email: dean.smce@mitaoe.ac.in there is a large effect of the ring to tube diameter ratio and ring arrays on thermal performance. Salam et al. [3] did an experimental investigation on rectangular cut twisted tape of stainless steel. They observed increment in the heat transfer efficiency in the range 1.9 to 2.3, with increment in Reynolds number. Eiamsa-ard et al. [4] used twisted tape inserts with peripherally cuts on it and conducted an experiment with uniform flux condition with Reynolds number ranging in between one thousand to twenty thousand. They found that the tube with his insert shows significantly higher heat transfer rate and friction factor mainly due to vorticity generated due to the cuts on the insert. Wongcharee et al. [5] investigated the effect of twisted tape insert placed inside a tube with alternate axes that is clockwise and counterclockwise with Reynolds number range of 830 to 1990 for different twist ratios with uniform heat flux and water as a working fluid. The results of the research show that the smallest twist ratio as very efficient in the enhancement of heat transfer. To study the effect of various types of inserts on heat transfer enhancement with this experimental work certain numerical study is carried out. Salman et al. [6] did numerical investigation on parabolic cut twisted tape and classical twisted tape with working fluid as water-copper oxide Nanofluid and it was observed that parabolic cut twisted tape shows better performance. Bhuyan et al. [7] studied heat transfer enhancement using full length twisted tape insert in a tabular shaped u loop pipes at a uniform flux. Results show that full length twisted tape shows better heat transfer enhancement in comparison with short length tapes. Eiamsa-ard et al. [8] did the study on loose fit twisted tape and tight fit twisted tape. It is found that at smallest clearance ratios there is a better performance in comparison with other all clearance ratio in terms of swirl flow generation and heat transfer rate. Sharifi et al. [9] had done a CFD study on wire coiled insert in laminar flow using hexahedral mesh. The result shows maximum Nusselt number and lowest performance drop for coiled wire for a pitch of 69mm. Guo et al. [10] had done investigation on heat transfer enhancement of laminar flow with center cleared twisted tape insert. In this study they compared the results from conventional, short width and center cleared twisted tape, concluding that twisted tape with center cleared tape shows augmentation in thermal performance factor showing best performance among all twisted tape stated. Park et al. [11] studied CFD analysis of Heat Transfer Enhancement and Flow Physics Behavior of Fluid in Circular Tube with Insert Shrinivas C. Deshmukh, Prashant W. Deshmukh, Prafulla R. Hatte