Numerical heat transfer in a solar air heater duct with punched delta-winglet vortex generators
The flow topology and thermohydraulic performance of a novel designed punched delta-winglet (P-DW) placed on the absorber of a solar air heater duct are numerically explored. The effects of geometrical parameters, namely, the relative winglet pitch, PR = 1–2 and the relative punched hole size, dR = ...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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Elsevier
2021-08-01
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| Series: | Case Studies in Thermal Engineering |
| Subjects: | |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S2214157X21002513 |
| _version_ | 1818728179541475328 |
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| author | Pongjet Promvonge Pitak Promthaisong Sompol Skullong |
| author_facet | Pongjet Promvonge Pitak Promthaisong Sompol Skullong |
| author_sort | Pongjet Promvonge |
| collection | DOAJ |
| description | The flow topology and thermohydraulic performance of a novel designed punched delta-winglet (P-DW) placed on the absorber of a solar air heater duct are numerically explored. The effects of geometrical parameters, namely, the relative winglet pitch, PR = 1–2 and the relative punched hole size, dR = 0–0.583 at a single value of blockage ratio, BR = 0.48 and attack angle, α = 30° on thermal characteristics are proposed for Reynolds number from 4000 to 24,000. Among several turbulence models, the simulation has shown that the realizable k–ε turbulence model is favorable with respect to measurements. For flow patterns, the P-DW produces several counter-spinning vortices helping induce the impinging jets onto the absorber surface whilst for thermal behaviors, the decline of PR and dR leads to the rise in the friction factor (f) and Nusselt number (Nu). The P-DW provides greater Nu and f than the plain flat plate by 17.1–78.21 and 3.92–5.9 times, respectively and gives the highest performance around 2.1. Further, the P-DW is modified by covering the punched hole partially with a circular flap, called the flapped delta-winglet (F-DW) and this F-DW yields the greatest performance around 2.16 higher than the P-DW about 2.9%. |
| first_indexed | 2024-12-17T22:25:53Z |
| format | Article |
| id | doaj.art-07185abdc2cd4df793cf77230ad8299a |
| institution | Directory Open Access Journal |
| issn | 2214-157X |
| language | English |
| last_indexed | 2024-12-17T22:25:53Z |
| publishDate | 2021-08-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Case Studies in Thermal Engineering |
| spelling | doaj.art-07185abdc2cd4df793cf77230ad8299a2022-12-21T21:30:21ZengElsevierCase Studies in Thermal Engineering2214-157X2021-08-0126101088Numerical heat transfer in a solar air heater duct with punched delta-winglet vortex generatorsPongjet Promvonge0Pitak Promthaisong1Sompol Skullong2Department of Mechanical Engineering, School of Engineering, King Mongkut's Institute of Technology Ladkrabang, Bangkok, 10520, ThailandHeat Pipe and Thermal Tool Design Research Unit (HTDR), Faculty of Engineering, Mahasarakham University, Maha Sarakham, 44150, ThailandEnergy Systems Research Group and ATAE Research Unit, Department of Mechanical Engineering, Faculty of Engineering at Sriracha, Kasetsart University Sriracha Campus, 199 M.6, Sukhumvit Rd., Sriracha, Chonburi, 20230, Thailand; Corresponding author.The flow topology and thermohydraulic performance of a novel designed punched delta-winglet (P-DW) placed on the absorber of a solar air heater duct are numerically explored. The effects of geometrical parameters, namely, the relative winglet pitch, PR = 1–2 and the relative punched hole size, dR = 0–0.583 at a single value of blockage ratio, BR = 0.48 and attack angle, α = 30° on thermal characteristics are proposed for Reynolds number from 4000 to 24,000. Among several turbulence models, the simulation has shown that the realizable k–ε turbulence model is favorable with respect to measurements. For flow patterns, the P-DW produces several counter-spinning vortices helping induce the impinging jets onto the absorber surface whilst for thermal behaviors, the decline of PR and dR leads to the rise in the friction factor (f) and Nusselt number (Nu). The P-DW provides greater Nu and f than the plain flat plate by 17.1–78.21 and 3.92–5.9 times, respectively and gives the highest performance around 2.1. Further, the P-DW is modified by covering the punched hole partially with a circular flap, called the flapped delta-winglet (F-DW) and this F-DW yields the greatest performance around 2.16 higher than the P-DW about 2.9%.http://www.sciencedirect.com/science/article/pii/S2214157X21002513Delta-wingletVortex generatorSolar air heaterThermal performanceFlow topology |
| spellingShingle | Pongjet Promvonge Pitak Promthaisong Sompol Skullong Numerical heat transfer in a solar air heater duct with punched delta-winglet vortex generators Case Studies in Thermal Engineering Delta-winglet Vortex generator Solar air heater Thermal performance Flow topology |
| title | Numerical heat transfer in a solar air heater duct with punched delta-winglet vortex generators |
| title_full | Numerical heat transfer in a solar air heater duct with punched delta-winglet vortex generators |
| title_fullStr | Numerical heat transfer in a solar air heater duct with punched delta-winglet vortex generators |
| title_full_unstemmed | Numerical heat transfer in a solar air heater duct with punched delta-winglet vortex generators |
| title_short | Numerical heat transfer in a solar air heater duct with punched delta-winglet vortex generators |
| title_sort | numerical heat transfer in a solar air heater duct with punched delta winglet vortex generators |
| topic | Delta-winglet Vortex generator Solar air heater Thermal performance Flow topology |
| url | http://www.sciencedirect.com/science/article/pii/S2214157X21002513 |
| work_keys_str_mv | AT pongjetpromvonge numericalheattransferinasolarairheaterductwithpuncheddeltawingletvortexgenerators AT pitakpromthaisong numericalheattransferinasolarairheaterductwithpuncheddeltawingletvortexgenerators AT sompolskullong numericalheattransferinasolarairheaterductwithpuncheddeltawingletvortexgenerators |