scholarly journals 3D Simulative Investigation of Heat Transfer Enhancement Using Three Vortex Generator Types Surrounding Tube in Plate Fin Heat Exchanger

2019 ◽  
Vol 130 ◽  
pp. 01027
Author(s):  
Stefan Mardikus ◽  
Petrus Setyo Prabowo ◽  
Vinsensius Tiara Putra ◽  
Made Wicaksana Ekaputra ◽  
Juris Burlakovs

Vortex generator is a method to enhancing of heat exchanger performance but still have some disadvantages when the heat transfer performance increase. One of the disadvantage using vortex generator is high pressure drop. This investigation will be compared three type vortex generators to result the overall performance of heat transfer around tube in plate fin heat exchanger. The three types of vortex generator to investigate are rectangular winglet type, delta winglet type, and trapezoidal winglet type in laminar flow. The result showed that using the kind of trapezoidal winglet pair type in the plate fin and tube heat exchanger consist of six rows of round tube with two neighboring fins form a channel better performance than two types vortex generators such as rectangular winglet type and delta winglet type. The heat transfer coefficient when use trapezoidal winglet type was increased almost same with rectangular winglet type and pressure drop was decreased more than delta winglet type.

2021 ◽  
Vol 39 (5) ◽  
pp. 1523-1531
Author(s):  
Katherine Barquín ◽  
Alvaro Valencia

Over the last decades several studies have searched for improved Fin and Tube Heat Exchanger (FTHE) designs capable of providing the best thermo-hydraulic performance. The present study aims at quantifying and comparing the thermo-hydraulic performance of different FTHE configurations. Six different designs were analyzed. The first FTHE consisted of an in-line circular tube arrangement and the last one was a FTHE with staggered oval tube with two pairs of Delta Winglet Vortex Generators (DWVG) in common flow up–common flow down (CFU-CFD) configuration. The best performance was obtained using DWVG in CFU-CFD orientation. This configuration enabled a 90% increase of the thermal performance factor when compared with the first case, using only two pairs of vortex generator´s per tube.


Energies ◽  
2020 ◽  
Vol 13 (19) ◽  
pp. 5219
Author(s):  
Jin-Cherng Shyu ◽  
Jhao-Siang Jheng

Because the delta winglet in common-flow-down configuration has been recognized as an excellent type of vortex generators (VGs), this study aims to experimentally and numerically investigate the thermo-hydraulic performance of four different forms of winglet VGs featuring sweptback delta winglets in the channel flow in the range 200 < Re < 1000. Both Nusselt number and friction factor of plate-fin heat sinks having different forms of winglets, including delta winglet pair (DWP), rectangular winglet pair (RWP), swept delta winglet pair (SDWP), and swept trapezoid winglet pair (STWP), were measured in a standard wind tunnel without bypass in this study. Four rows of winglets with in-line arrangement were punched on each 10-mm-long, 0.2-mm-thick copper plate, and a total of 16 pieces of copper plates with spacing of 2 mm were fastened together to achieve the heat sink. The projected area, longitudinal and winglet tip spacing, height and angle of attack of those winglets were fixed. Besides that, three-dimensional numerical simulation was also performed in order to investigate the temperature and fluid flow over the plate-fin. The results showed that the longitudinal, common-flow-down vortices generated by the VGs augmented the heat transfer and pressure drop of the heat sink. At airflow velocity of 5 m/s, the heat transfer coefficient and pressure drop of plain plate-fin heat sink were 50.8 W/m2·K and 18 Pa, respectively, while the heat transfer coefficient and the pressure drop of heat sink having SDWP were 70.4 W/m2·K and 36 Pa, respectively. It was found that SDWP produced the highest thermal enhancement factor (TEF) of 1.28 at Re = 1000, followed by both RWP and STWP of similar TEF in the range 200 < Re < 1000. The TEF of DWP was the lowest and it was rapidly increased with the increase of airflow velocity.


2013 ◽  
Vol 136 (2) ◽  
Author(s):  
Hamdi E. Ahmed ◽  
M. Z. Yusoff

This paper presents the laminar forced convection of Al2O3–water nanofluid in a triangular channel, subjected to a constant and uniform heat flux at the slant walls, using delta-winglet pair (DWP) of vortex generator which is numerically investigated in three dimensions. The governing equations of mass, momentum, and energy are solved using the finite volume method (FVM). The nanofluid properties are estimated as constant and temperature-dependent properties. The nanoparticle concentrations and diameters are in ranges of 1–4% and 25–85 nm, respectively. Different attack angles of vortex generators are examined which are 7 deg, 15 deg, 30 deg, and 45 deg with range of Reynolds number from 100 to 2000. The results show that the heat transfer coefficient is remarkable dependent on the attack angle of vortex generators and the volume fraction of nanoparticles. The heat transfer coefficient increases as the attack angle increases from 7 deg to 30 deg and then diminishes at 45 deg. The heat transfer rate remarkably depends on the nanoparticle concentration and diameter, attack angle of vortex generator and Reynolds number. An increase in the shear stress is found when attack angle, volume fraction, and Reynolds number increase.


Author(s):  
Guidong Chen ◽  
Jing Xu ◽  
Ming Zen ◽  
Qiuwang Wang

In order to improve heat transfer performance of conventional segmental baffled shell-and-tube heat exchangers (STHXs), the shell-and-tube heat exchanger with combined helical baffles (CMH-STHX) were invented. In the present study, the CMH-STHX is compared with three other STHXs which were set up with continuous helical baffles (CH-STHX), discontinuous helical baffles (DCH-STHX) and segmental baffles (SG-STHX), by Computational Fluid Dynamics method. The numerical results show that, for the same mass flow rate at the shell side, the overall pressure drop of the CMH-STHX is about 50% and 40% lower than that of SG-STHX and CH-STHX. The heat transfer coefficient of the CMH-STHX is between those of CH-STHX and DCH-STHX and it is 6.3% lower than that of SG-STHX. The heat transfer coefficient under unit pressure drop h/Δp is introduced to evaluate the comprehensive performance of STHXs. The h/Δp of the CMH-STHX is 7.5%, 6.5% and 87.4% higher on average than those of the CH-SHTX, DCH-STHX and SG-STHX. Furthermore, the total heat transfer rate of CMH-STHX is about 25% higher than that of SG-STHX for the same total pressure drop of shell side. Supported by these results, the new heat exchanger (CMH-STHX) may be used to replace the conventional shell-and-tube heat exchanger in industrial applications.


ROTASI ◽  
2018 ◽  
Vol 20 (2) ◽  
pp. 124
Author(s):  
Syaiful Syaiful ◽  
MSK Tony Suryo Utomo ◽  
Hengky Dwi Febriandy

Fin and tube heat exchanger adalah salah satu penukar kalor compact yang digunakan dalam berbagai aplikasi, seperti pada industri petroleum, industri kimia, industri HVAC dan indistri otomotif. Oleh karena itu peningkatan performa termal pada heat exchanger perlu untuk dilakukan. Salah satu cara untuk meningkatkan performa termal pada heat exchanger adalah dengan meningkatkan koefisien perpindahan panas konveksi pada fluida. Pada studi sekarang ini, eksperimen dilakukan untuk mengetahui beberapa parameter yang mempengaruhi perbaikan perpindahan panas. Eksperimental dilakukan dengan memasang vortex generators pada sudut serang 15, 30 dan 45 dengan susunan satu, dua dan tiga baris di dalam saluran persegi empat. Pada eksperimen ini, concave delta winglet vortex generators (CDW VGs) dan tanpa vortex generator (baseline) diinvestigasi. Kecepatan udara masuk ke dalam saluran persegi empat ditentukan pada rentang 0.4-2.0 m/s dengan interval 0.2 m/s dengan laju panas konstan 35 W pada plat dimana vortex generators ditempelkan. Pada kasus tiga baris DWP VG dengan sudut serang 45̊, koefisien perpindahan panas konveksi rata-rata meningkat 1,68 kali lebih besar daripada baseline. Sedangkan pada kasus tiga baris CDWP VGs dengan sudut serang 45̊, koefisien perpindahan panas konveksi rata-rata meningkat 1,76 kali lebih besar daripada tiga baris DWP VG.


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