Jet Plate Research Articles

Energy-economic-environmental analysis of bifacial photovoltaic thermal (BPVT) solar air collector with jet impingement

Jet impingement cooling enhances photovoltaic (PV) system efficiency by using high-speed fluid jets to reduce panel temperatures, improving performance and longevity. The effectiveness depends on factors like fluid flow rate, nozzle placement, and distance from the panel. While it boosts energy output, it may increase energy use for fluid circulation and add complexity to the system. This research explores a groundbreaking approach to enhancing the efficiency of bifacial photovoltaic thermal (BPVT) systems by integrating jet impingement technology. A novel design featuring a jet plate reflector is introduced, offering the dual benefit of cooling the PV panels while simultaneously reflecting light to optimize energy capture. The study comprehensively analyses the system’s performance, including energy output and a detailed techno-economic and environmental-economic evaluation. The modelling in this study was validated and reasonably consistent with experimental results. The system's output air temperature and thermal efficiency are 302.07–318.75 K and 33.83–62.28 %, respectively. The temperature and electrical efficiency range for PV systems are 304.39–339.54 K and 9.39–11.22 %. Reduced mass flow rate and increased solar irradiation are the most economically advantageous operating parameters for the proposed system, resulting in lower annual pumping costs and more significant annual energy gains for the system. CBR variations range from 0.1363 to 9.3445, with an average of 2. Additionally, by using BPVT with jet impingement to generate electricity rather than fossil fuels, it is possible to reduce annual carbon dioxide emissions by approximately 1.61 tons and save RM93.51 annually. In general, the proposed method should be used to minimize environmental pollution.

Influence of corrugated jet plates on internal heat transfer and flow dynamics of double-wall cooling: experimental-numerical approach

In the present study, combined experimental and numerical investigations were carried out to analyze the fluid flow dynamics and heat transfer of impinging jets in a corrugated double-wall structure for exhaust nozzle cooling operating at high temperatures. The sinusoidal wavy plate, with multi-jet holes positioned at its trough, served as the jet plate, creating a staggered configuration with respect to the effusion holes. The transient thermochromic liquid crystal (TLC) method was employed to determine the local distribution of the Nusslet number on the flat effusion plate in a wind tunnel at small Reynolds numbers (ranging from 450 to 2700 based on the jet hole diameter (d)). In the numerical part of the study, the k-ω SST turbulence model verified with the TLC data was used to solve the RANS equations. The effects of jet-to-plate spacing (Have/d = 1.6–3.6), corrugated plate amplitude (A/d = 0.2–0.8), effusion hole diameter (de/d = 0.6–1.5), and Reynolds numbers were examined in detail. Our results showed that the introduction of the corrugated structure in the jet plate altered the high-velocity region pattern within the jet hole, leading to a 16 %-81 % reduction in jet core length compared to the flat jet plate. At a relatively high wave amplitude (A/d ≥ 0.5), the vortex structure underwent significant changes, inducing a higher level of turbulence kinetic energy in the near-wall region of the target chamber. This led to enhanced heat transfer near the stagnation and effusion hole regions compared to the flat double-wall cooling. The effusion hole diameter exerted a minimal effect on the overall Nusselt number of the corrugated double-wall cooling. At very low Reynolds numbers (Rej 〈900), the flow and heat transfer characteristics in corrugated double-wall cooling resembled those observed in flat double-wall cooling.

Jet array impingement heat transfer in a rectangular cavity with effusion holes

Various researchers have studied jet array impingement heat transfer in impingement/effusion cooling systems. However, there is a lack of research on impingement/effusion cooling systems installed within rectangular cavities that focus on the impact of the proximity of the jet hole to the cavity sidewalls on cooling performance. The main objective of this study is to investigate the flow and heat transfer characteristics of jet array impingement with effusion holes in a rectangular cavity, considering various spacings between the cavity sidewalls and the outermost jet hole. The design parameters in this study include the ratio of the jet hole pitch to jet hole diameter of 7.1, 10.0, and 16.7, and the ratio of the distance between the jet and impingement plates to jet hole diameter of 2, 6, and 10, with the Reynolds number based on the jet hole diameter ranging from 2500 to 15,000. Heat transfer characteristics in the stagnation region and wall jet region were examined using local Nusselt number distributions on the impingement surface, measured by liquid crystal thermography. The local Nusselt number was high in the stagnation region and decreased radially from the stagnation region as the wall jet region formed. The closer the outermost jet hole is to the sidewall, the higher the Nusselt number on the impingement surface near the sidewall. Moreover, the flow structure in the rectangular cavity was numerically investigated, and the velocity vectors and streamlines showed that primary and secondary vortices were generated in the middle of two neighboring jets and near the sidewall, respectively. This study also assessed previous average Nusselt number correlations. Based on experimentally determined average Nusselt number data with 54 center unit cells and 1296 side unit cells, new correlations to predict the average Nusselt number on the impingement surface in a rectangular cavity with effusion holes were developed.

Integrated Thermal Management System Concept With Combined Jet Plate, High Porosity Aluminum Foam, and Target Plate for Enhanced Heat Transfer

Abstract An experimental investigation was carried out on high porosity metal foams subjected to array jet impingement with an objective to develop enhanced heat transfer configurations. In this study, we propose an integrated thermal management system (TMS) aimed toward leveraging the conjugate heat transfer capabilities of target plate, metal foam, and the jet plate—all made from aluminum and assembled such that a proper contact between them can be established. Steady-state heat transfer experiments were carried out for 10 and 20 pores per inch (PPI) aluminum foams of 0.93 porosity. Both metal foams were 12.7-mm thick. The normalized jet-to-jet spacing was varied from 2 to 12 times the jet diameter, while the jet diameter was fixed. The ratio of the jet plate thickness and jet diameter (nozzle aspect ratio) was 6.35, which ensured proper development of jets inside the nozzles. Experiments were conducted over a wide range of Reynolds number (based on jet diameter) varied from 100 to 5000. The obtained convective heat transfer coefficient for different configuration was evaluated in context with pressure drop. The analysis of experimental results reveal that large open area ratio jets combined with high porosity metal foams provide highly efficient and high-performance cooling for the investigated range of Reynolds numbers.

Analisis Tenaga Pesentakan Jet Aliran Pekeliling Terbalik (PJAPT) Ke Atas Pengumpul Fotovolta Terma Suria (PVT) Modul Dwimuka

Although photovoltaic thermal (PVT) offers ascertain of benefits, it also has its own limitations. The efficiency of PVT is diminished due to heat gain experienced by its photovoltaic module when subjected to solar radiation. Jet impingement has been recognised as a highly successful technique for the purpose of cooling solar modules, particularly in the context of bifacial module applications. An energy analysis of a reversed circular flow jet impingement on a bifacial PVT collector was perform through an indoor experiment utilizing a solar simulator. The jet plate outlet was varied into four different configurations: one hole (1h), three holes (3h), four holes (4h) and five holes (5h) to identify the jet plate outlet configuration that contributes to the best energy efficiency. The experiment was carried out using a constant solar irradiance of 900 W/m2 and mass flow rate between 0.01 kg/s to 0.14 kg/s. The study’s findings indicate that configuration 1h exhibited the best photovoltaic efficiency of 11.09%. Additionally, the highest thermal efficiency recorded was 63.2%. In summary, it can be concluded that configuration 1h exhibits an overall photovoltaic thermal efficiency of 74.28% when subjected to a mass flow rate of 0.14 kg/s. This configuration outperforms other jet plate outlet configuration in terms of energy performance.

Effect of the partial blockage in the exit of the mixing channel on thermo - Hydraulic performance of the multi – Pass jet plate solar air heater

The present experimental work deals with the effect of partial blockage in the exit of the mixing channel on thermo-hydraulic performance of multi-pass jet plate solar air heater. This investigation is performed at IIT(ISM) Dhanbad campus (India) to obtain the results in terms of outlet temperature, collector efficiency, Temperature rise parameter (TRP), thermo - hydraulic performance parameter (THPP) and Nusselt number for double–pass cross and non–cross flow inline holes Jet Plate Solar Air Heater (JPSAH). Results for different ranges of operating and geometrical parameters such as, mass flow rate = 0.10–0.14 kg/s, Reynolds number, Re = 4741–10632, daily average solar flux incident on glass cover, Itavg. = 611–1113 W/m2 and blockage ratio (H/Z2) = 0, 0.33, 0.66 are presented. This work also compares the present results with simple double – pass solar air heater. It is found that the maximum percentage increments in THPP and Nu are 37 % and 79 % respectively at Re = 10247 and 9500 for BR = 0 compared to non-cross flow and simple double pass solar air heater. Based on the experimental data, correlations for the Nusselt number, friction factor and THPP have been developed.

Thermo-hydraulic and exergetic analysis of rectangular channel with integrated jet impingement and roughness

ABSTRACT This experimental study investigates an innovative approach to enhance surface heat transfer efficiency by employing V-pattern protrusions in conjunction with an impinging air jet. The synergy between surface roughness and the air jet induces heightened turbulence, resulting in significantly improved heat transfer performance. Various parameters on a jet plate, such as relative streamwise spacing (X/Dh), relative spanwise spacing (Y/Dh), and relative jet diameter (dJ/Dh), were systematically explored over a Reynolds number range of 4,000 to 18,000, representing the operational range. Optimal thermo-hydraulic efficiency was achieved at specific parameter values: relative streamwise spacing (X/Dh) of 1.7, relative spanwise spacing (Y/Dh) of 0.86, and relative jet diameter (dJ/Dh) of 0.086. Statistical correlations were established based on experimental data for both Nusselt number and friction factor. Furthermore, an exhaustive exergetic analysis was conducted to evaluate the thermal system’s sustainability, potential for waste heat recovery, and avenues for improvement. This study’s significance lies in its pioneering approach to augmenting heat transfer through the novel integration of V-pattern protrusions and impinging air jets. The results not only delineate optimal parameter configurations for enhancing heat transfer but also provide insights into system sustainability, waste heat recovery potential, and broader applications. By amalgamating distinct techniques, this research advances the existing literature by achieving superior thermal performance.

Computational Fluid Dynamics: Flow Analysis on The Effect of Different Jet Orifice Angle Multi Circular Jet for Fuel and Air Mixing

The mixing of fuel and air plays a major role in the spray and flame behavior, hence affecting the combustion performance and emissions of the internal mixing air-assisted atomizers. Air-assisted atomizers are introduced to counter the low-pressure differential of a simplex nozzle, which reduces the atomization quality. The present study aims to determine the effects of Multi Circular Jet (MCJ) plates on the geometrical configurations of internal flows in mixing chamber and the internal flow of plate 3 using different properties of fuel. In this study, the realizable k-ε turbulence model, specifically designed for strongly swirling flows, is validated through numerical simulations. The turbulence model selected is a type of Reynolds averaged Navier-Stokes (RANS) model called the k-ε model. The MCJ plates provide the primary air entrance into the mixing chamber. Additionally, it acts as a turbulence generator and can be adjusted to alter the flow of fuel and air mixtures in a mixing chamber. The study compares several MCJ geometries in terms of pressure, speed, turbulent kinetic energy, and volume fraction and compares the performances of diesel and Crude Palm Oil (CPO) B30 biodiesel fuels. The findings imply that CPO B30 biodiesel has superior atomization and mixing due to its higher density and turbulent kinetic energy. CPO B30 biodiesel was compared to Diesel in terms of maximum pressure, average speed, turbulent kinetic energy per unit mass, and volume fraction. The results indicate that CPO B30 has lower pressure and higher velocity than Diesel, suggesting better fuel atomization and mixing. The higher density of CPO B30 leads to increased turbulent kinetic energy, improving fuel-air mixing inside the combustion chamber. The study demonstrates that the use of MCJ plates can enhance mixing in a mixing chamber. In addition, MCJ plates show the ability to control the spray and atomization. The findings of this study contribute to a better understanding of the relationships between geometry and fuel-air mixing, as well as the characteristics of the internal mixing air-assisted atomizer, which will lead to future burner system improvements.

Acoustic characterization of an installed elliptical jet

This work demonstrates a preliminary acoustic characterization of an installed elliptical jet with an aspect ratio of 2. This configuration is compared against the nominal axisymmetric installed jet case of equivalent diameter. A baseline case for the elliptical and axisymmetric nozzle geometries are obtained in the uninstalled configuration. For all cases, the acoustic Mach number is varied between 0.4 and 1.0, the azimuthal observer angle between 0° and 90°, and the axial distance from the jet exit to the observer between 0 and 30 nozzle equivalent diameters. The latter of these is an analogue for polar angle variation by keeping the radial distance from the jet to the observer constant. A flat metal plate is used for the installed case, creating a jet–plate interaction mimicking that of an aircraft engine’s exhaust and its wing. Using the same variations as the free jet, parameters such as plate height, trailing-edge distance and, for the elliptical jet, nozzle exit rotation angle are investigated to give a broad characterization of the installed elliptical jet and enable direct comparison to the axisymmetric jet case. The key comparison metric for this work is the overall sound pressure level and polar directivity of the acoustic fields.

Heat Transfer and Pressure Loss Correlations for Leading Edge, Jet Impingement Using Racetrack-Shaped Jets With Filleted Edges

Abstract This paper presents an experimental investigation of heat transfer and pressure loss for leading-edge jet impingement using racetrack-shaped jets. The majority of literature for gas turbine cooling applications considers jet impingement using square or sharp-edged orifices. However, the edge of the jet orifices generally has some degree of filleting (or rounding) along the edges, due to casting the airfoils or material wear due to long-term operation. Engineers need data under realistic engine configurations to improve the utilization of coolant while adequately protecting the airfoil. The current experimental study is a parametric investigation of heat transfer and pressure loss for leading-edge jet impingement, where the effects of jet Reynolds number (Re = 10,000–100,000), jet–to–jet spacing (s/d = 2–8), jet–to–target surface spacing (z/d = 2–4), surface curvature (D/d = 2.67–5.33), and jet fillet–to–jet plate thickness (r/l = 0.16–0.5) are each considered. The edge rounding at both the inlet and outlet of the jet plate yields reduced heat transfer compared to the square-edged jets. However, the fillets significantly improve the discharge coefficients associated with the racetrack-shaped orifices. With the extensive testing completed in this study, design correlations have been developed to predict the surface Nusselt number and discharge coefficients, with 10% and 19% deviation from experimental results, respectively. Engine designers can predict the level of heat transfer and pressure loss for leading-edge jet impingement using these correlations.

Exergetic Performance of Jet Impingement Bifacial Photovoltaic-Thermal Solar Air Collector with Different Packing Factors and Jet Distributions

Jet impingement is a promising cooling mechanism to increase the rate of heat transfer in solar air collector. However, the effects of an impinging air jet on the exergetic performance of a bifacial photovoltaic-thermal with different packing factors are entirely unclear. In this research, a jet impingement bifacial photovoltaic-thermal solar air collector was developed and its exergetic performance was assessed. Jet plate reflectors with different geometric configurations are proposed to enhance the cooling and light absorption at the rear part of the bifacial photovoltaic module. Additionally, the link between exergetic performance and each variable’s design and operational characteristics was examined through indoor experiments. The results showed that the maximum exergy efficiency of the bifacial photovoltaic-thermal with packing factor of 0.66 and 36-hole jet plate reflector has 11.88% under solar irradiance of 900 W/m2, and mass flow rate of 0.025 kg/s. The maximum exergy input, exergy destruction, and improvement potential of the proposed system are 402.81 W, 345.62 W, and 304.78 W, respectively.

Experimental analysis of thermal performance of SAH with impinging jet having varying length of perforated jet plate

An experimental setup of an impinging jet solar air heater (IJSAH) was developed to study its thermal and frictional characteristics. Six cases were analysed with the jet holes spanning different lengths across the jet plate. For cases 1 and 2, jet holes spanned 100% and 80% of the length of the jet plate while having jet diameter equal to 3 mm. For cases 3,4, and 5, jet holes were drilled up to 100%, 80%, and 60% of the entire length and the diameter was increased to 6 mm. For case 6, jet holes were drilled up to 100% while keeping jet diameter equal to 9 mm. For each case, variation in Nusselt number, friction factor and temperature rise of the fluid was evaluated for Reynolds number in the range 4913 to 13,103. The efficiency and thermo-hydraulic performance factor with each case were compared. It was concluded that IJSAH with reduced length of drilled section (case 5) developed similar performance to IJSAH having completely perforated jet plate (case 1) while developing significantly lower friction factor. The temperature rise of the fluid and the friction factor developed for case 5 were around 10% and 40% lower than case 1, respectively.

Effect of jet plate thickness on the local heat transfer coefficient with multiple air jet impingement

For designing a multiple jet impingement cooling system, the thickness of jet plate (a passage through which jet comes out) is one of the important parameters. Considering the thermal point of view, the thickness of the plate should be chosen so that it would enhance the heat transfer rate. In this study, the effect of jet plate thickness on the local heat transfer coefficient on a flat plate with multiple impinging air jets is investigated. The thickness ratios (t/d) of 0.5, 1.0 and 2.67 are studied. Reynolds number is varied from 5000 to 20,000 and jet-to-plate distance (z/d) is varied from 1 to 5. Jet diameter (d) is chosen to be 6 mm. The jet-to-jet distance (p/d) is kept constant at 3.Steady-state thin metal foil technique, along with infrared thermography, is used to obtain the temperature distribution and thereby the heat transfer coefficient. Coefficient of discharge for each jet plate, central line velocity decay and pressure distribution on the target surface are measured. These measurements provided new insights to better understand the heat transfer results in this study. For lower jet-to-plate distances (t/d = 0.5 to 1), heat transfer decreases with the increase in the jet plate thickness ratio. However, heat transfer is not affected with the further increase in the jet plate thickness ratio i.e., t/d = 1 to 2.67. Therefore, smaller jet plate thickness ratio is suitable to obtained high heat transfer rate. This study presents a new correlation for the local Nusselt number distribution or different jet plate thickness.

Analysis of Elliptical-Jet Acoustic Directivity and Efficiency Using a Vortex-Sheet-Based Wave-Packet Model

The hydrodynamic characteristics and associated far-field acoustics of installed elliptical jets were studied using linear models based on the Navier–Stokes equations. A compressible elliptical vortex-sheet model predicted that the growth rates of the varicose and wagging modes decreased with the aspect ratio, whereas the growth rate of the flapping mode increased, which was consistent with previous studies using finite-thickness stability models. Using a propagation model adapted from the Lighthill acoustic analogy, it was found that the acoustic efficiency of the “varicose” mode is significantly higher than the “flapping” and “wagging” modes for both free- and installed jets. Increasing the aspect ratio of the elliptical jet produces a slight reduction in sound for the mode, a significant decrease in the mode, and a significant increase for the mode. A similar trend was observed for the installed case. An exponential relationship between the jet–plate distance and scattered sound was found for elliptical jets, as observed for circular jets. Other geometric parameters such as the orientation angle of the ellipse were also analyzed.

Investigation of impingement heat transfer in double-wall cooling structures with corrugated impingement plate at small Reynolds numbers

This study investigated an impingement/effusion cooling scheme with a corrugated jet plate applicable to a high-temperature exhaust cooling nozzle. The primary objective was to evaluate the effect of the corrugated wall jet on the impingement heat transfer and flow loss in a narrow target chamber under a low jet Reynolds number ranging from 450 to 2700. Sinusoidal curves with different wavelengths were employed to model the corrugated jet plate, where impingement holes were located at the trough of the plate. The location of the impingement holes creates a staggering pattern relative to the effusion holes. The corrugated jet plates with relative ripple amplitudes (A/d) considered were 0.2, 0.5 and 0.8, and the results were compared with those of a flat jet plate. Three relative average jet-to-plate spacings, Have/d, were selected for use: 1.6, 2.6, and 3.6. The heat transferred over a smooth target surface by multiple jets was measured using the transient liquid crystal (TLC) method. Results show that the amplitude of the corrugated plate was found to profoundly influence the heat transfer of the target surface. The use of corrugated jet plates yielded a better heat transfer performance at a relatively high Re and low impinging distance. The optimal heat transfer performance was achieved at A/d of 0.5, which was 28 % higher than the flat plate. The discharge coefficient for the corrugated jet plate was 2–9.4 % lower than that of the flat jet plate at all Have/d and Re values, and the minimum discharge coefficient was reached at A/d of 0.2. Furthermore, internal impingement heat transfer and flow resistance characteristics of the corrugated impingement/effusion were correlated according to the experimental data.

Heat transfer enhancement by V-shaped protrusions on jet plate under different crossflow conditions

Heat transfer enhancement by V-shaped protrusions on jet plate under different crossflow conditions

Heat Transfer Enhancement in Tubular Heat Exchanger with Jet Impingement: A Review

Heat exchanger (HE) is a thermal device used to transfer heat from higher fluid temperatures to lower fluid temperatures. There is an increasing need to increase the efficiency of HEs, develop a wide range of investigations to increase heat transfer rate (HTR), and reduce the size and cost of industrial apparatus in accordance. The current work's goal is to review articles that discuss the main types of tubular heat HEs, factors that affect HTR, and jet impingement in tubular HEs, which are considered among the equipment used in various industries. Researchers have proposed several models of tubular HEs. Many industrial processes, cooling technology, refrigeration equipment, sustainable energy applications, and other fields use tubular HEs. Jet impingement cooling is assumed to be a very efficient method for increasing HT rate, and it has many uses in both the scientific and industrial spheres. This paper's goal is to present an overview of various techniques for improving HT in relation to jet impingement cooling and to define the area of potential future research. This study focuses on a variety of experimental and numerical studies to examine the HT and hydrodynamic behaviour of jet impingement over a range of Reynolds numbers, target surface shapes, distances from the jet plate or nozzle to the target plate, extended jet holes, and the use of nanofluids. Both single jet and multiple jet impingements cooling are included in the current work. The summary of jet impingement for various applications keeps the spotlight on new methods for enhancing HT.

Effect of new design of elongated jet hole on thermal efficiency of solar air heater

Effect of new design of elongated jet hole on the thermal efficiency (ηth) of a solar air heater (SAH) has been numerically studied in this paper. Jet impingement technique, which is one of the important active techniques, has been implemented on the absorber plate of the SAH surface to increase the convective heat transfer performance. Several designs of elongated jet hole (EJH) technique (gradually increasing, gradually decreasing along the crossflow direction, and equally extended), which is highly effective application to get rid of cross-flow, has been inserted to the jet plate. The main interest of this paper is to investigate the effect of different EJH configurations on convective heat transfer performance and ηth of the SAH. 15 × 7 array of jets have been mounted on the confinement plate. Results have been compared with the conventional SAH, which has the jet impingement Case1. Numerical computations have been conducted using RNG k-ε turbulence model. Average Nusselt number (Nu) on the absorber plate surface, ηth of the SAH, and performance evaluation criteria (PEC) have been quantitatively investigated comprehensively. As a result of calculations, the Nu and ηth of SAH can be enhanced by 31.80 % and 2.46 %, respectively, using Case4 instead of Case1 at Re = 25000. Besides, the pressure drop of SAH dramatically rises by 10.26 %, when Case4 and Case1 compared with each other at Re = 25000. Despite increment in pressure drop, the PEC value achieves to 1.28. Finally, it is concluded that the equally extended EJH presents well performance compared to gradually increasing and decreasing EJH.

Effect of metal foam thickness on the conduction and convection heat transfer for a flat plate with metal foam impinged by multiple jets

ABSTRACT The influence of metal foam thickness on the convection and conduction heat transfer is studied by measuring the local heat transfer of a smooth flat plate, attached and detached metal foamed flat plate under multiple jet impingement conditions. 27 jets of 3 mm diameter are introduced from a jet plate. These jets impinge on a thin stainless steel foil that serves as a targeted plate. The pitch of the jets is 4d in both the spanwise and streamwise directions. The spent fluid is exiting in all directions. The influence of metal foam thickness is investigated for an open-cell aluminum foam with 4, 8, and 12 mm thickness. The porosity of aluminum metal foam is 0.92. The pore density (pores per inch) is 20 PPI. The local heat transfer is measured using infrared thermography and a thin metal foil technique. A smooth flat plate impinged by multiple jets serves as a reference case. The evaluation of the convection and conduction heat transfer offered by the metal foamed flat plate is obtained with the help of the detached foam configuration. The jet diameter-based Reynolds number ranges from 2500 to 15000. The range of the jet to plate spacing covered is 3d to 6d. Depending on the metal foam thickness, the metal foamed flat plate offers additional hydraulic resistance to the jet flow and conduction effect. The additional hydraulic resistance attenuates the convective heat transfer and is represented by attenuation factor (α). For metal foam having 4, 8, and 12 mm thickness, the attenuation factor is around 1.11, 0.99, and 0.64, respectively. The conduction effect offered by metal foam is responsible for the enhancement of the heat transfer. The conduction effect is represented as an enhancement factor (E). For metal foam having 4, 8, and 12 mm thickness, the enhancement factor is around 1.51, 1.58, and 2.32, respectively. The conduction effect presented in the metal foamed flat plate dominates over the attenuation in the convective heat transfer. The overall enhancement offered by 4, 8, and 12 mm metal foamed flat plate is around 1.67, 1.56, and 1.48, respectively.

Efficiency enhancement of solar air heater collector by modifying jet impingement with v-corrugated absorber plate

The current work involves an experimental investigation of a modified v-corrugated absorber plate to get a better performance of the Solar Air Heater (SAH) collector. The thermal efficiencies of the modified and the normal v-corrugated collector having a jet plate blown systems are compared to present the actions of the modified system. The modified system is named Model-1, whereas the normal system is called Model-2. The experimentation has been done in winter 2021 in Mosul city, Iraq. The results confirm that the thermal efficiency of Model-1 is more efficient than Model-2 by 11.5 %, 14.5 %, 12.3 % and 13.2 % for 0.009 kg/s, 0.018 kg/s, 0.028 kg/s and 0.037 kg/s, respectively. The optimum thermal performance for Model-1 and Model-2 have been obtained for 0.037 kg/s and equal 82.3 % and 69.1 %, respectively. A substantial temperature difference has been found in Model-1 in comparison with Model-2. The highest outlet temperature of Model-2 is always lower than Model-1 for all mass flowrate. The enhancement in the thermal efficiency of Model-1 indicates that the use of the modified model has a considerable effect on the heat exchange efficiency.