Promvonge, Pongjet
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Preferred name
Promvonge, Pongjet
Alternative Name
Promvonge, P.
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Email
pongjet.pr@kmitl.ac.th
16 results
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Item type:Publication, Augmented thermal effectiveness in solar air receiver with flapped curved winglets: Experimental and numerical analysis(2025-12-01) ;Sripattanapipat, Somchai; ; ;Promthaisong, PitakNakhchi, Mahdi ErfanianThermal effectiveness was examined on a solar air receiver equipped with a new lengthwise vortex generator, namely a flapped curved winglet (FCW) mounted on the absorber, utilizing experimental and numerical approaches. Two arrays were employed to assemble two FCWs on the absorber at an angle of attack (α = 59.5°). The FCWs' V-tips were orientated upstream (VU-FCW) and downstream (VD-FCW). Air served as the working fluid, entering a constantly heat-fluxed channel at Reynolds numbers (Re) varying from 5280 to 22,510. Three relative winglet pitches (P<inf>R</inf> = P/H = 1.0–2.0), five winglet-mounted flap angles (β = 0° - 90°), and one winglet blockage ratio (b/H=B<inf>R</inf> = 0.6) were among the major factors. According to the findings, lowering P<inf>R</inf> and β greatly enhances the f (friction factor) and Nu (Nusselt number) of the two FCW arrays. The FCW with P<inf>R</inf> = 1.0 and β = 0° has the largest Nu and f values, approximately 8.3 and 77.39 times bigger than the smooth flat channel, as per the test data. The maximal thermal effectiveness factors (TEF) of the VD-FCW and VU-FCW were approximately 2.83 and 2.61, respectively, at comparable β = 45° and P<inf>R</inf> = 1.5. The f and Nu correlations in employing FCW were also provided. A 3D computational analysis employing the realizable k-ε turbulence model was conducted to examine heat transmission and flow patterns, with the corresponding measured data validating the expected results. The numerical and measured data sets yielded consistent results, and the FCW's heat transmission mechanism was also described. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Enhanced thermal effectiveness of square duct with V-type double-baffles: Numerical study(2024-09-01); ;Sripattanapipat, Somchai; ;Skullong, SompolPromthaisong, PitakThe article puts forward three-dimensional computational research on heat transmission augmentation within a square channel containing 45<sup>o</sup> V-type double-baffles positioned on the lower and top parts at regular intervals in the turbulence zone for Reynolds numbers (Re) that vary from 3000 to 20,000. The primary goal of this research is to increase the thermal effectiveness and relative Nusselt number (Nu/Nu<inf>0</inf>), in order to conserve energy and reduce the size of the heating or cooling system. The simulations utilize a finite volume approach in common with the SIMPLE algorithm, whereas the turbulent model used is the realizable k–ε. The baffles are designed to be separated vertically for reducing pressure loss. Both single V-baffles and double V-baffles have four relative pitches (PR = 0.4, 0.5, 0.6, and 1.0) and height/blockage ratios (BR = 0.05, 0.1, 0.15, and 0.2), with a fixed attack angle (α) of 45<sup>o</sup>. The computational findings show that both V-baffles are capable of producing the primary vortices, but only the double V-baffles have the ability to provide the impinging streams onto the wall, cooling the region behind the baffles. This suggests that the double V-baffles not only boost heat transmission but also reduce frictional loss. When compared to a single V-baffle, the double ones enhance heat transfer by an average of 1.04–9.94% while decreasing frictional loss by an average of 9.88–31.73%. The thermal effectiveness factor (TEF) of the double V-baffles ranges from 1.03 to 3.21, and its peak value of around 3.21 is for PR = 0.4, BR = 0.05, at lower Re. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Experimental and numerical thermal performance in solar receiver heat exchanger with trapezoidal louvered winglet and wavy groove(2022-04-01); ;Promthaisong, PitakSkullong, SompolA numerical and experimental study on the thermal–hydraulic performance of a solar receiver heat exchanger (SRH) equipped with a newly designed longitudinal-vortex generator, namely, trapezoidal louvered winglet and wavy groove placed on the absorber has been carried out. The relevant parameters included three pitch ratios of winglets/grooves (P/H = P<inf>R</inf> = 1, 1.5 and 2), four winglet blockage ratios (b/H = B<inf>R</inf> = 0.3–0.45) at a single attack angle of winglet/groove, α = 45°. The experimental outcome showed that the trapezoidal winglet (TW) together with the wavy groove at P<inf>R</inf> = 1, B<inf>R</inf> = 0.45 gives the greatest friction factor and the heat transfer around 108.1 and 9.35 times over the smooth SRH channel, respectively while that at P<inf>R</inf> = 1.5, B<inf>R</inf> = 0.4 provides the optimal thermal performance at about 2.6. To increase further the performance, the TW at optimal conditions was modified by punching the TW at its centroid to be a square-hole and then covering the back-end hole partially like a louver, called the trapezoidal louvered winglet (TLW). The TLW elements were mounted on the grooved absorber plate with eight louver angles (θ = 0°–90°). The investigation indicated that among the louver angles, the θ = 20° yields the greatest heat transfer up to 9.18 times above the smooth SRH whilst its friction loss is lower than the θ = 0°(solid-winglet). Hence, the TLW and wavy groove at θ = 20° provided the maximum thermal–hydraulic performance around 2.76. To understand the flow and thermal patterns, a 3D flow computation was also carried out and their results were validated with available measurements. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Thermo-Hydraulic Performance of a Heat Exchanger Tube with Inserted Curved-Wing Tape Vortex Generators(2024-10-24) ;Koolnapadol, Narin; ;Promthaisong, Pitak ;Hoonpong, PanuwatKhanoknaiyakarn, ChitakornIn the current study, thermal patterns and flow resistance in a heat exchange tube equipped with a curved-wing tape (CWT) vortex generator were experimentally analyzed to boost performance. A range of Reynolds numbers (Re) from 4130 to 25,370 was utilized in the experiment. The curved wings were arranged in forward array patterns for pitch length ratios (P/D = PR = 2.5, 2, and 1.5) and three wing attack angles (α = 10°, 20°, and 30°). The friction factor, f, and the Nusselt number, Nu, were utilized to quantify the pressure loss and heat transmission caused by the CWT insertion. The measured data reveal that utilizing the CWT resulted in a roughly 2.55-4.37 times greater increase in Nu than the smooth tube, whereas the rise in f is approximately 7.36-46.9 times. Raising the α value causes the Nu and f to trend upward, but increasing PR causes them to trend downward. The CWT's maximal thermal performance is approximately 1.58 at α = 10<sup>o</sup> and PR = 1.5. Correlations for f and Nu in the functional form of the CWT parameters have also been established. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Heat transfer augmentation in solar heat exchanger duct with louver-punched V-baffles(2022-12-01); ;Promthaisong, PitakSkullong, SompolA vortex generator's ability to create secondary flow and accelerate rapid fluid mixing allows it to effectively improve thermal performance in a solar heat exchanger duct. A newly created louver-punched V-baffle (LPVB) vortex generator was tested experimentally in the current study and the flow and thermal patterns were also investigated using a three-dimensional CFD simulation. The Realizable k–ε turbulence model was utilized in the simulation and the predictions were verified using experimental data and correlations. By directing the impinging air onto the duct's heated surface, the square louver on the baffle served the primary function of reducing pressure drag. Air was used as the test fluid, flowing at Reynolds numbers (Re) from 5300 to 23,000 into the constant heat-fluxed duct. On the heated wall that was set up by letting the V-apex direct upstream, the LPVBs with a 45° attack angle (α) were repeatedly positioned. There were two aspects to the current investigation. First, the optimal relative baffle pitches (P<inf>R</inf>) and louver angles (β) conditions were determined by looking at the LPVB characteristics, which included four β and three P<inf>R</inf> at a fixed relative louver size (L<inf>R</inf> = 0.5) and baffle height (B<inf>R</inf> = 0.4). Second, three relative louver sizes (L<inf>R</inf> = 0.3–0.9) were investigated at the optimal P<inf>R</inf> and β. According to the results, the solid-baffle friction loss is significantly reduced by the LPVB with β > 0° while the heat transfer is slightly lower. In the first part, the LPVB with P<inf>R</inf> = 1.5, β = 45° has the optimal performance while in the second part, the one with L<inf>R</inf> = 0.9 yields the greatest performance. A numerical flow model was computed to understand the flow and thermal patterns. The findings were verified using the available measurements, and there is close agreement between the experimental and numerical results. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Experimental and numerical heat transfer study of turbulent tube flow through discrete V-winglets(2020-04-01); ;Promthaisong, PitakSkullong, SompolThe article presents an experimental and numerical investigation on heat transfer augmentation in a tubular heat exchanger inserted with discrete-V-winglet (DW) tape. Air entered the DW-inserted tube having a uniform wall heat flux in a turbulent flow regime, Reynolds number from 4200 to 25,800. Two arrangements of DWs: V-tip pointing upstream (V-up) and downstream (V-down) were introduced with three relative winglet heights (R<inf>B</inf>=b/D = 0.1, 0.15 and 0.2) and four relative winglet-pitches (R<inf>P</inf>=P/D = 0.5, 1.0, 1.5 and 2.0), all at a single angle of attack, α = 30°. Effects of those parameters on the heat transfer/Nusselt number (Nu) and friction factor (f) were examined. Also, a novel thermal-performance enhancement factor (TEF) was put forward. The experimental result has shown that at a given R<inf>B</inf>, the smallest pitch length (R<inf>P</inf>=0.5) yields the highest f and Nu. The DW with R<inf>B</inf>=0.2 and R<inf>P</inf>=0.5 has the maximum Nu and f of about 3.8 times and 18.8 times, respectively whereas the one with R<inf>B</inf>=0.15 and R<inf>P</inf>=1.0 gives the highest TEF of about 1.99 and 2.02 for the V-up and V-down, respectively. Moreover, the DW provides higher TEF than the typical V-winglet as expected. To explore the mechanism of heat transfer, a numerical model of the inserted-tube flow was carried out and the numerical result was validated and found in favorable agreement with available measurement. Flow structures and heat transfer patterns from the simulation such as temperature contours and streamlines including the Nusselt number contours were also proposed. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Effect of louvered curved-baffles on thermohydraulic performance in heat exchanger tube(2023-02-01); ; ; ;Promthaisong, PitakSkullong, SompolThe paper presents an experimental study of convection enhancement in a tube heat exchanger using louvered curved-baffle (LCB) vortex generator (VG). The heat transfer and pressure loss of air as a working fluid, flowing in an isothermal-fluxed tube were measured having Reynolds numbers (Re) between 4760 and 29,300. The LCB elements were arrayed on two tape sides in a V-shape with a 30° attack angle. At a fixed baffle height, the LCB had three axial pitch ratios (PR) from 0.5 to 1.5 and six louver angles (θ) from 0° to 90°. Thermal enhancement factor (TEF), Nusselt number (Nu), and friction factor (f) are often utilized to analyze the effect of VG geometrical variables on thermohydraulic performance. The measured results demonstrated that the LCB-inserted tube has a significantly larger Nu and f than a plain tube functioning alone, and that the Nu and f tend to rise when PR and θ decline. Using the LCB increases Nu and f by approximately 2.59-4.66 and 3.8-39.37 times, respectively. The maximal TEF is achieved for the LCB at PR = 1, θ = 45° and lower Re. Empirical correlations for Nu and f were evaluated and found to fit measured data well, with discrepancies by ± 9% and ±10%, respectively. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Numerical heat transfer in a solar air heater duct with punched delta-winglet vortex generators(2021-08-01); ;Promthaisong, PitakSkullong, SompolThe 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%. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Enhanced thermal performance in solar receiver duct with louver-punched V-type winglets: Numerical and experimental study(2025-03-01); ;Sripattanapipat, Somchai ;Promthaisong, Pitak ;Skullong, SompolAn experimental and computational research was performed to explore the augmentation of turbulent convection in a solar receiver channel by utilizing louver-punched V-type winglets (LPVWs) that were fixed to the absorber plate. The simulation utilized the realizable k-ε turbulent model, and the predicated outputs were verified by the relevant measured data. At a fixed attack angle (α) of 45°, the LPVW components were mounted on the absorber with the V-tip facing downstream. Using the LPVW, the newly developed absorber is intended to boost thermal performance by generating multiple flows of longitudinal vortices that induce impinging air streams onto the absorber, thereby enhancing heat transmission. The louvered hole on the winglet serves to reduce pressure loss while preserving the primary vortices. In the current investigation, the winglet parameters consisted of a single relative winglet height (B<inf>R</inf> = 0.4), four louver size ratios (R<inf>L</inf> = e<inf>1</inf>/b = 0.9, 0.7, 0.5, and 0.3), and five louver-flapped angles (β = 90°, 60°, 45°, 30°, and 0°). The LPVW with β > 0° substantially reduced the solid-winglet (β = 0°) friction loss, whereas the heat transmission was slightly declined, as indicated by the results. The solid winglet (β = 0°) exhibited the largest frictional loss and heat transmission, with values approximately 6.3 and 48.2 times the smooth flat duct, respectively. The optimal performance of the LPVW was roughly 2.58, at R<inf>L</inf> = 0.9 and β = 45° Furthermore, empirical correlations for heat transmission and frictional loss were established for this solar receiver duct system. To investigate the heat transmission and flow patterns, a 3-dimensional numerical simulation was implemented, and the predictions were verified against the measured data. The findings were in good accord between the numerical and measured data. For greater thermal performance, the LPVW is reconfigured by altering the locations of the louver holes. The revised LPVW exhibits a peak TEF of 2.7 at β = 35°, l<inf>2</inf>/l<inf>1</inf> = 0.15, l<inf>3</inf>/l<inf>1</inf> = -0.15 and R<inf>L</inf> = 0.9, about 4.65 % superior than the initial analysis. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Numerical Heat Transfer Investigation in a Solar Receiver Heat Exchanger Channel with Punched Elliptical-Winglet Vortex Generators(2021-01-01) ;Promthaisong, Pitak; ;Khanoknaiyakarn, ChitakornSkullong, SompolThermal performance in a solar receiver heat exchanger (SRX) channel with punched elliptical-winglet vortex generator (P-EW) mounted on the absorber plate is numerically examined for Reynolds number (Re) ranging from 4000 to 24,000. In the present simulation, the P-EW characteristics included three ratios of winglet pitches (P<inf>R</inf> = 2.0, 1.5 and 1.0) including four sizes of the perforated-holes (nondimensional hole diameter, d<inf>R</inf>= 0.0, 0.25, 0.417 and 0.583) at one value of the attack angle (α =30°) and relative height (B<inf>R</inf>= 0.48). The computation reveals that employing P-EW generally yields considerably large friction factor (f) and Nusselt number (Nu) than the flat-plate channel alone. The use of smaller hole size causes the rise in Nu and f. It is noticeable that counter-spinning vortices pairs generated by the multiple P-EW can induce the impinging flow onto the absorber plate together with the air jet coming out of the hole, leading to the rise in the heat transfer rate greater than the smooth flat-plate channel. The highest thermal performance of about 1.9 was seen for the one with P<inf>R</inf> = 1.5 and d<inf>R</inf> = 0.417.
