KMITL

Permanent URI for this communityhttps://dspace.kmitl.ac.th/handle/123456789/1

Browse

Settings

Author: search.filters.author.Kwankaomeng, SutapatSubject: search.filters.subject.Winglet

Search Results

Now showing 1 - 2 of 2
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Publication,
    Enhanced heat transfer in a triangular ribbed channel with longitudinal vortex generators
    (2010-06-01)
    Promvonge, Pongjet
    ;
    Chompookham, Teerapat
    ;
    Kwankaomeng, Sutapat
    ;
    Thianpong, Chinaruk
    Effects of combined ribs and winglet type vortex generators (WVGs) on forced convection heat transfer and friction loss behaviors for turbulent airflow through a constant heat flux channel are experimentally investigated in the present work. The cross-section of the ribs placed inside the opposite channel walls to create a reverse flow is an isosceles triangle shape. Two rib arrangements, namely, in-line and staggered arrays, are introduced. Also, two pairs of the WVGs with various attack angles (α) of 60°, 45° and 30° are mounted on the test duct entrance to create a longitudinal vortex flow through the test channel. Measurements are carried out for a rectangular duct of aspect ratio, AR = 10 and height, H = 30 mm with a single rib height, e/H = 0.13 and rib pitch, P/H = 1.33. The flow rate is in terms of Reynolds numbers based on the inlet hydraulic diameter of the channel ranging from 5000 to 22,000. The experimental results show a significant effect of the presence of the rib turbulator and the WVGs on the heat transfer rate and friction loss over the smooth wall channel. The values of Nusselt number and friction factor for utilizing both the rib and the WVGs are found to be considerably higher than those for using the rib or the WVGs alone. The larger the attack angle value leads to higher heat transfer and friction loss than the lower one. The in-line rib together with the WVGs provides higher heat transfer and friction loss than the staggered one for similar operating conditions. In common with the WVGs, the in-line rib yields the highest increase in both the Nusselt number and the friction factor but the rib with staggered array shows better thermal performance than the others. © 2010 Elsevier Ltd. All rights reserved.
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Publication,
    Heat transfer augmentation in a wedge-ribbed channel using winglet vortex generators
    (2010-02-01)
    Chompookham, Teerapat
    ;
    Thianpong, Chinaruk
    ;
    Kwankaomeng, Sutapat
    ;
    Promvonge, Pongjet
    Experimental investigations have been carried out to study the effect of combined wedge ribs and winglet type vortex generators (WVGs) on heat transfer and friction loss behaviors for turbulent airflow through a constant heat flux channel. To create a reverse flow in the channel, two types of wedge (right-triangle) ribs are introduced: wedge ribs pointing downstream and pointing upstream. The arrangements of both rib types placed inside the opposite channel walls are in-line and staggered arrays. To generate longitudinal vortex flows through the tested section, two pairs of the WVGs with the attack angle of 60° are mounted on the test channel entrance. The test channel has an aspect ratio, AR = 10 and height, H = 30 mm with a rib height, e/H = 0.2 and rib pitch, P/H = 1.33. The flow rate in terms of Reynolds numbers is based on the inlet hydraulic diameter of the channel ranging from 5000 to 22,000. The presence of the combined ribs and the WVGs shows the significant increase in heat transfer rate and friction loss over the smooth channel. The Nusselt number and friction factor values obtained from combined the ribs and the WVGs are found to be much higher than those from the ribs/WVGs alone. In conjunction with the WVGs, the in-line wedge pointing downstream provides the highest increase in both the heat transfer rate and the friction factor while the staggered wedge pointing upstream yields the best thermal performance. © 2009 Elsevier Ltd. All rights reserved.