@Article{hmt.16.17,
AUTHOR = {Amnart Boonloi, Withada Jedsadaratanachai},
TITLE = {THERMAL PERFORMANCE ASSESSMENT IN A CIRCULAR TUBE  FITTED WITH VARIOUS SIZES OF MODIFIED V-BAFFLES: A  NUMERICAL INVESTIGATION},
JOURNAL = {Frontiers in Heat and Mass Transfer},
VOLUME = {16},
YEAR = {2021},
NUMBER = {1},
PAGES = {1--16},
URL = {http://www.techscience.com/fhmt/v16n1/52536},
ISSN = {2151-8629},
ABSTRACT = {This research reports numerical examinations on fluid flow, heat transfer behavior and thermal performance analysis in a circular tube equipped with 
modified V-baffles (CTMVB). The modified V-baffle (MVB) is a combination vortex generator between V-baffles/V-orifices which are placed on 
the tube wall and V-baffles which are inserted at the core of the tested tube. The MVB height is separated into two parts; b1 represents the MVB 
height on the tube wall, while b2 represents the MVB height at the core of the tested round tube. The MVB height to tube diameter ratios, b/D, are 
adjusted; b<sub>1</sub>/D = 0.05, 0.1, 0.15 and 0.2, and b<sub>2</sub>/D = 0.025, 0.05, 0.075 and 0.1. The Reynolds numbers of about 100 – 2000 (laminar regime) are 
considered. The flow directions in the tested section; V-tip directing downstream and V-tip directing upstream, are discussed. The flow attack angles 
for the MVB, α, of about 20o and 30o are compared. The finite volume method with SIMPLE algorithm (a commercial code) is opted to analyze the 
present investigation. The computational domain of the CTMVB is validated (grid independence and smooth tube validations). It is found that the 
MVB generates many vortex cores in the tested section. The vortex flows near the tube wall disrupt thermal boundary layer, while the vortex flows at 
the center of the tube help superior fluid blending. The disturbed thermal boundary layer and the better fluid blending are main two causes for heat 
transfer augmentation. In addition, the best thermal enhancement factor of the CTMVB is found to be around 3.92.},
DOI = {10.5098/hmt.16.17}
}