Thermal System Research Articles

The Use of Thermal Data for Quality Assurance in the Process of Continuous Ultrasonic Welding of Thermoplastic Composite Materials

Continuous ultrasonic welding (CUW) is a manufacturing process used to join thermoplastic composite materials using high-frequency ultrasonic vibrations. Under pressure and vibration, the welding material heats up, melts and the welding partners are joined while they are cooling down. The development of CUW is getting raised attention over the last decade since the use of thermoplastic composites (TCs) in the production industry and especially the aerospace sector demands for economic and fast joining techniques. In order to establish this welding technique in the industry it is necessary to develop methods which enable to do quality assurance on the produced welding seams. In the experiments described in this paper the potential of thermal measurements for the quality assurance of the ultrasonic welding of TCs is investigated. Different thermal systems are evaluated and it is described how the data of the most promising technique is further processed and fed to an artificial intelligence (AI) algorithm. The here trained networks are created to predict lab-shear-strength values and reach mean absolute error scores of below 1 MPa. The described investigations hint that thermography seem to be a valuable resource to make more reliable quality assurance in the process of CUW of TCs and therefore might help to establish the use of this welding technology further in the industry.

Probabilistic design and optimization of thermal protection system with variable thickness based on non-uniform aerodynamic heating

Thermal Protection System (TPS) is a critical component of space vehicles to protect them from damage by extreme aerothermal heating conditions. The uncertainty of the aerothermal heating conditions, including approaching velocities, atmospheric density, pressure, etc., significantly affects the aerothermal heating imposed on the TPS, vastly changing the initial design conditions. In this study, we developed a new uncertainty quantitative (UQ) analysis method to comprehensively consider all the uncertainty of TPS materials, structures, and aerothermal heating conditions. To address the challenges of a massive amount of input and determined optimization parameters, we first induced the response surface method and Monte Carlo algorithm to produce a large number of analysis samples for Probabilistic Design. Then, the key affecting factors, not all the input design parameters, were chosen for optimization with sequential optimization and reliability assessment (SORA) strategy by a sensitivity analysis. With such improvements, the optimization for UQ analysis becomes practical. We used this new UQ method to analyze the effects of uncertainty of the aerothermal heating conditions on the thermal protection layer. A variable thickness design is proposed to adapt the non-uniform aerothermal heating conditions for the TPS. The results show that significant light-weighting can be achieved without the reliability penalty. The optimized structure also reduces internal temperature gradients and facilitates a more uniform temperature field distribution for the TPS. This study provides a new UQ engineering design approach for the system with many designed parameters.

Role of aloe vera based nanofluids for cool thermal energy storage system: A comparative study

The present experimental investigation incorporates the preparation of aloe vera gel-based phase change nanofluid (NFPCM) for a cool thermal energy storage (CTES) system. Two sets of NFPCMs were produced by adding graphene nanoplatelets (GNP) in deionized water and aloe vera gel (0.20 wt%, 0.40 wt%, and 0.60 wt%). The zeta potential analysis shows that the NFPCM with aloe vera gel is more stable even after 60 days from the preparation (−44 mV). The thermal conductivity of NFPCMs was analyzed through the transient hot wire method and the enhancement of 42 %, and 37.5 % were measured in the ice phase for NFPCMs with aloe vera gel and DI water (0.60 wt%) respectively at the heat transfer fluid temperature of −15 °C. The NFPCMs with aloe vera gel show that the addition of GNP prepended the peak melting temperature from −16 °C to −10.5 °C, which is due to the quick formation of nuclei as compared to NFPCMs with DI water. Additionally, a slight reduction in the latent heat of only 7 % was observed. The charging characteristics of NFPCMs were studied in a single spherical capsule at −8 °C. The maximum reduction in total charging time of 25 % was recorded for the aloe vera gel-based NFPCM with a maximum concentration of GNP (0.60 wt%). The green synthesis of aloe vera gel-based NFPCM exhibited noteworthy enhancements in thermophysical properties. Additionally, it was observed that the long-term stability of the NFPCM was achieved by excluding surfactants during the preparation process. The incorporation of graphene nanoplatelets (GNP) into aloe vera gel as the foundational phase change material (PCM) facilitates the partial charging of the CTES system with a reduced energy input.

Expression of concern for article entitled “Numerical analysis of pressure drop and heat transfer of a non-Newtonian nanofluids in a Li-ion battery thermal management system (BTMS) using bionic geometries”

Expression of concern for article entitled “Numerical analysis of pressure drop and heat transfer of a non-Newtonian nanofluids in a Li-ion battery thermal management system (BTMS) using bionic geometries”

Analysis and design of module-level liquid cooling system for rectangular Li-ion batteries

To promote energy conservation and emission reduction, the electric vehicles (EVs) are developing rapidly. An effective battery thermal management system (BTMS) can extend the service life of batteries and avoid thermal runaway. In this study, a liquid-cooling management system of a Li-ion battery (LIB) pack (Ni-Co-Mn, NCM) is established by CFD simulation. The effects of liquid-cooling plate connections, coolant inlet temperature, and ambient temperature on thermal performance of battery pack are studied under different layouts of the liquid-cooling plate. Then, A new heat dissipation scheme, variable temperature cooling of the inlet coolant, is proposed. Results indicate that connecting two sets of liquid coolant plates in a 3-series, 1-parallel configuration can effectively reduce the maximum temperature of the battery pack from 48.73 ℃ to 30.75 ℃, while controlling the maximum temperature difference to 3.98 ℃ at the end of discharge. Simultaneously, the proposed cooling scheme reduces the maximum temperature difference within the battery pack by 36.09 % at the beginning of the discharge period. This study provides a valuable reference into advancing BTMSs of battery pack-level for EVs.

Influence of hot water consumption patterns on the viability of low-temperature solar thermal systems in the food industry

The thermal demand in agri-food industries is characterised by its considerable variability, hindering the implementation of Solar Water Heating Systems (SWHS). The main objective of the study is to provide an overview of how consumption patterns influence the profitability and energy savings of SWHS in the sector, while also identifying additional key variables that affect their viability. For this purpose, approximately 1,300,000 cases have been examined, considering a wide range of consumption patterns, economic variables, and locations. Demand seasonality, weekly frequency and energy prices exhibit the greatest impact on the feasibility of SWHS. Uniformity of daily demand, location and investment cost are also determinants. Thus, single-day-per-week consumption patterns make SWHS unviable in most scenarios. However, with only three non-consecutive days, feasibility increases significantly, achieving paybacks of less than 5 years and energy savings of over 40% when conditions are highly favourable. In strongly seasonal industries, the viability of SWHS is seriously compromised. The payback in patterns with a peak consumption in the early morning can double the value with uniform one (e.g., from 4 to 8 years in the most favorable scenarios at a price of 0.1 €/kWh). The results tables reflecting payback and energy savings in thousands of different scenarios represent a valuable tool for decision-making in industries. By looking for the scenario with the most similar characteristics, it is possible to estimate the profitability and savings of the SWHS in a given industry, as well as the possible variations when changing the assumed variables.

Assessing the Applicability of Solar Thermal Technologies for Industrial Tea Drying

Most process heat being used for various industrial applications is supplied from fossil fuels. Coal, gas, and wood fuel are the most used heat resources which usually power steam boilers for production of heat used in a wide range of industrial processes. Since economic growth is largely linked to industrial production, it implies that, a shift towards use of clean energy technologies in industries is crucial to meet the rising demand of process heat while, cutting down carbon emissions to mitigate climate change. Solar thermal systems have over the past years shown potential as a practical alternative to fossil fuels for production of heat for several applications including, water and space heating, industrial process heating and electricity generation in thermal power plants. This study seeks to assess the feasibility of employing solar thermal technologies for drying purposes at Tingamira-Tanganda Tea estate in Zimbabwe. Systems advisor model (SAM) was applied to simulate performance of linear Fresnel (LF) and parabolic trough (PT) solar thermal technologies for industrial tea drying. Information on daily heat demand, required process temperatures and current heat sources was obtained to inform the design process of the proposed solar thermal systems. LF system exhibited better techno-economic performance. It requires a smaller collector area (360 m2) with a lower initial capital cost which is about 8% cheaper. Moreover, it produces higher annual energy at lower levelized cost of heat for solar multiples higher than 1. Carbon footprint of the factory would be reduced by about 114 tonnes CO2 annually. Sensible thermal energy storage technology can be considered for back up heat and heat recovery.

AN AI-BASED SURVEILLANCE SYSTEM PROPOSAL FOR THE SECOND LINE OF DEFENSE AGAINST IRREGULAR MIGRATION, SMUGGLING, AND TERRORISM: GENDARME ASSESSMENT

Despite the physical and technological measures in place along the border protected by border forces, a significant number of irregular migrants are being apprehended by gendarmerie (Jandarma) elements in the area designated as the second line of defense. This situation poses a crucial responsibility for the Jandarma in the context of preventing irregular migration movements, curbing smuggling activities, and combating terrorism. Therefore, it is proposed that artificial intelligence-supported technological discovery and surveillance measures be implemented in the Jandarma responsibility area behind the border. It is believed that these technological measures could be beneficial in preventing irregular migration movements, restricting smuggling activities, and enhancing effectiveness in the fight against terrorism. The implementation of these measures could contribute to public safety by increasing security and maintaining order. Within the scope of this study, a thermal camera network system powered by solar energy, featuring wireless communication capabilities, and equipped with artificial intelligence analysis, is described. Additionally, the technical architectural features of the system, installation requirements, and details of the artificial intelligence algorithms to be utilized within the system, along with their capabilities and potential algorithm specifics, are explained. The implementation of the proposed system is anticipated to enhance reconnaissance and surveillance capabilities.

Co-treating flue gas desulfurized effluent and produced water enables novel waste management and recovery of critical minerals

This study reports a novel approach of resource recovery from co-managing two geographically co-located and chemically complementary wastewaters using a pilot-scale treatment process. Designed to treat flue gas desulfurized (FGD) effluent from combustion powerplants and produced water (PW) from energy industries, the process consists of soda-ash softening, nanofiltration (NF), and reverse osmosis (RO). Recovered products are barite, calcite, and low-salinity water. Using field-collected waters, the results show that softening at pH ≈ 8.5 produces calcite (yield: ~30 kg/m3 treated water), a chemical used as SO₂(g) scrubbers. NF treatment under an applied pressure of ~3.5 MPa yields a permeate stream laden with monovalent ions (water recovery ~60 %) and a concentrate stream with a sulfate concentration ~1.8 times of the feedwater concentration. Mixing the NF concentrate and PW at a volumetric ratio of 1.0 precipitates a high-density barite material (4.1 g/cm3, yield: ~7.5 kg/m3 mixture) – a critical mineral commonly used as a weighting agent in drilling. The RO treatment recovers >64 % water as the permeate, which can be readily used as cooling make-up water at the powerplants. The RO concentrate stream can be further processed in a thermal evaporative system for additional water recovery and brine production.

Thermal radiation image recognition camera using target detection techniques with human computer interaction

Backgroundand Purpose: The evolution of object detection methodologies has shifted from conventional approaches to modern deep learning architectures to overcome limitations in handling object variations. The goal was to introduce YOLO, a groundbreaking architecture enabling real-time object detection, leading to the development of an AI camera using YOLO for thermal imaging object recognition. This innovation aimed to precisely identify animals, humans, and plants in thermal images while providing a user-friendly experience. MethodologyTraditional methods' limitations were highlighted, emphasizing YOLO's single-pass architecture and its integration into the AI camera system, aligning with Human-Computer Interaction principles. This AI camera system can detect object between Animals, Humans and plants. Stratified K-Fold Cross-Validation was utilized to refine the AI model, ensuring accuracy and generalization by representing object classes proportionally. ResultsEmploying Stratified K-Fold Cross-Validation achieved an overall 97.55% detection accuracy and 85.75% sensitivity, showcasing the AI model's robustness. Comparative analysis with R-CNNs revealed YOLO's 18% accuracy improvement, affirming its superiority and strategic implementation in the AI camera system. These findings validated YOLO's efficiency in thermal image object detection. ConclusionThe conclusion highlights the profound impact of YOLO, specifically within the domain of thermal image recognition, substantiating its incorporation into the AI camera system in adherence to Human-Computer Interaction (HCI) principles. The commendable precision of YOLO, coupled with its real-time capabilities and user-centric design, has resulted in the development of an advanced thermal image object detection system, representing a notable advancement in the field of object recognition technology.

Target temperature-based simulation method for predicting performance and designing aircraft thermal anti-icing systems

The prevention of ice build-up on aircraft surfaces is crucial for safe operations. Thermal ice protection systems, particularly electro-thermal systems, are commonly employed to mitigate ice formation. However, the weight of electric batteries used in these systems significantly impacts aircraft performance, necessitating the minimization of power load during design. Despite this requirement, effective anti-icing operation mandates a sufficient heat flux to maintain surface temperature above the freezing point and evaporate any runback water film. Previous research has utilized numerical simulation analysis to predict the performance of electro-thermal anti-icing systems. The conjugate heat transfer method has been commonly employed to predict temperature distribution on the protected surface. However, non-isothermal surfaces exhibit distinct local convective heat transfer coefficients that influence local thermal balance, unlike isothermal surfaces that adopt the loosely-coupled method for computational efficiency. In this study, we present a novel target temperature-based anti-icing simulation method that predicts the required heat flux for thermal ice protection systems without employing the conjugate heat transfer method. Our objective was to calculate the necessary heat flux to achieve the desired non-isothermal surface temperature for effective anti-icing. By eliminating the excessive iteration process associated with the coupling method for conjugate heat transfer, we have streamlined the simulation procedure. Through validation, target temperature-based anti-icing simulation method, when compared to the tight coupling method, demonstrated the ability to predict the same surface water flow rates while reducing computation time by up to 90 %. Furthermore, when applied to design problems, our method achieved approximately a 10 % reduction in the required heat capacity for anti-icing compared to experimental values. As a result, target temperature-based anti-icing simulation method offers a more efficient alternative to traditional conjugate heat transfer methods, providing valuable insights for both predicting anti-icing system performance and optimizing aircraft design.

Feasibility and efficacy of single-shot PFA technology for redo procedures after a previous atrial fibrillation ablation procedure

Abstract Introduction Despite significant technological advancements and a better understanding of atrial tachyarrhythmia pathophysiology, a non-negligible percentage of atrial fibrillation (AF) patients undergoing catheter ablation experiences arrhythmia relapse. Repeat procedures have been traditionally performed via thermal energy systems, which carry a certain risk of collateral damage to adjacent tissues. Pulsed Field Ablation (PFA) has emerged as an alternative non-thermal energy source for cardiac ablation. The main advantage is its selectivity to cardiac tissue. FarapulseTM is the first PFA technology to have received regulatory approval and includes a pentaspline PFA catheter. Although designed for pulmonary vein isolation, its use for extrapulmonary vein site ablation has been previously documented. Purpose To evaluate the feasibility and efficacy of the pentaspline FarawaveTM for redo procedures. Methods Patients referred for a redo procedure using FarapulseTM system were enrolled in 3 high-volume European centers. A workflow (Figure 1.A) was established based on rhythm at presentation (Group 1: sinus rhythm; Group 2: AFL; Group 3: AF). Results A total of 117 patients were included (64 in Group 1, 18 in Group 2, and 35 in Group 3). The mean number of previous procedures was 1.26, and 23 patients (19.66%) had already undergone ≥2 procedures. Previous ablation targets included PVI, either alone (46.15%) or in combination with other targets, including posterior mitral line (39.32%), posterior wall (6.84%), or anterior mitral line (2.56%). Electroanatomical mapping (EAM) was adopted in 15.38% of the cases. Specifically, in 27.78% (n=5) of group 2, 15.63% (n=10) of group 1 and 8.57% (n= 3) of group 3 cases. Additional focal radiofrequency ablation was required in 4 patients for CTI line ablation. Lesion sets are depicted in Figure 2. Mean procedural and LA dwelling time were 95.2 ± 38.0 and 50.7 ± 36.7 minutes, respectively. There was a total of one major complication (intracranial haemorrhage) and 5 minor complications (two vascular site related, and three reversible ST segment changes, related to applications on the mitral annulus area). A total of 100 patients completed at least 3 months of follow-up (FU), with a median FU time was 7.55 months (IQR 5.18 – 11.85). The total number of recurrences was 20, including 2 during the blanking period. Survival function (excluding blanking period) was 88.6 (95% CI 79.7 – 93.8) at 6 months and 80.0% (95% CI 67.3 – 88.3) 12 months. Atrial arrhythmia free-survival was higher in patients presenting in sinus rhythm, compared to the other two groups (p = 0.0135), as displayed in Figure 1.B. Conclusion The proposed stepwise approach to repeat AF ablation procedures based on the use of the single-shot PFA system (with or without EAM) was feasible, safe, fast and effective at one year follow-up.Flow chart and Kaplan Meier curveLesion sets

Design and evaluation of an AR-based thermal imaging system for planning reconstructive surgeries.

Thermal imaging can be used for the non-invasive detection of blood vessels of the skin. However, mapping the results to the patient currently lacks user-friendliness. Augmented reality may provide a useful tool to superimpose thermal information on the patient. A system to support planning in reconstructive surgery using a thermal camera was designed. The obtained information was superimposed on the physical object using a Microsoft HoloLens. An RGB, depth, and thermal camera were combined to capture a scene of different modalities and reconstruct a virtual scene in real time. To register the different cameras and the AR device, an active calibration target was developed and evaluated. A Vuforia marker was used to register the hologram in the virtual space. The accuracy of the projected hologram was evaluated in a laboratory setting with participants by measuring the error between the physical object and the hologram. The AR-based system was evaluated by 21 participants in a laboratory setting. The mean projection error is 10.3 ± 9.4mm. The system is able to stream a three-dimensional scene with augmented thermal information in real time at 5 frames per second. The active calibration target can be used independently of the environment. The calibration target provides an easy-to-use method for the registration of cameras capturing the visible to long-infrared spectral range. The inside-out tracking of the HoloLens in combination with a Vuforia marker is not accurate enough for the intended clinical use.

Experimental exploration of nano-phase change material composites for thermal management in Lithium-ion batteries

The present study reports an experimental investigation carried out for the thermal management of cylindrical lithium-ion battery simulator using aluminium oxide (nano particle)-eicosane (phase change material) composites. The experiment involves varying the power input from 4 to 10 W in 2 W increments and adjusting the weight percentage of nanoparticles (wt %) from 0.5 to 0.9 in 0.2 wt % intervals. The examination of battery temperature evolutions in response to heating power, a comprehensive heat transfer analysis incorporating Nusselt number, determination of maximum temperature difference, thermal resistance analysis, and exploration of temperature variations in the absence of Phase Change Material (PCM) are considered. The results show that increase in weight percentage of alumina nanoparticles in phase change material cannot always improve the thermal performance. The results of the present study give a guideline for designing battery thermal management system. The power levels used in the experiment vary from 4 W to 10 W in steps of 2 W. For a power level of 4 W, the heat flux is 1.088 kW/m2, and for a power level of 10 W, the heat flux is 2.72 kW/m2.

Effect of graphene coating on flow boiling in a minichannel at sub-atmospheric pressures

Flow boiling in a mini-channel with graphene-coated sintered porous copper surface was investigated at sub-atmospheric pressures by analyzing bubble motion and flow patterns. A method of surface modification based on graphene coating was presented for thermal management systems operating at lower temperatures. The experiments were carried out at mass fluxes of 60 kg.m–2.s–1 and 120 kg.m–2.s–1 and sub-atmospheric pressures of 48 kPa and 68 kPa in a mini-channel with dimensions of 50 mm × 15 mm × 2 mm using HFE-7100 coolant as the working fluid. At sub-atmospheric pressures, the bubble nucleation site density decreases, and the bubble diameter increases while the bubble release frequency decreases. The existence of porous surfaces and HFE-7100 coolant with lower surface tension leads to the inception of boiling at lower wall superheats. The graphene coating promotes microlayer evaporation and consequently increases the nucleation site density by enhancing the thermal conductivity and wicking rate. Additionally, it provides stable annular flow at high heat fluxes, whereas intermittent-annular flow is observed for the untreated surface under the same condition. This enhancement results in a more pronounced increase in the boiling heat transfer for the graphene-coated surface. As a result, this study provides the high potential of graphene coatings for phase change heat transfer enhancement at sub-atmospheric pressures.

Thermal image processing system to monitor muscle warm-up in students prior to their sports activities

INTRODUCTION: Muscle warm-up plays a fundamental role before developing any physical activity because it allows the body to prepare to perform better in physical activity, being a process that is carried out through a series of moderate intensity exercises that result in an increase gradual reduction of muscle and body temperature, avoiding possible injuries or muscle pain. Therefore, muscle warm-up is an essential activity mainly in those sports where greater force is exerted on the legs, being the part of the body where injuries such as ankle sprains or knee injuries are commonly seen that lead to painful and uncomfortable injuries for students-athletes.OBJECTIVES: Develop a thermal image processing system to monitor the muscle warm-up of students prior to their sports activities to evaluate the state of the muscle warm-up of the leg part and prevent damage or injuries, as well as the indication of requiring another additional muscle warm-up to determine a correct muscle warm-up.METHODS: The proposed method involves the use of thermal images to monitor muscle warm-up before and after physical activity. In addition, the use of MATLAB software to analyze the images and compare the status of muscle warm-up.RESULTS: Through the development of this proposed system, its operation was appreciated with an efficiency of 95.97% in monitoring the muscle warm-up of the students prior to their physical activities achieved through image processing.CONCLUSION: It is concluded that the proposed system is effective in monitoring muscle warm-up and preventing injuries in student-athletes.

Finite difference simulation of natural convection of two-phase hybrid nanofluid along a vertical heated wavy surface

This study employs finite difference modelling to investigate the natural convection of a two-phase hybrid nanofluid consisting of Al 2 O 3 and Cu nanoparticles dispersed in water along a vertically heated wavy surface. The hybrid nanofluid has unique features that influence convective heat transfer. Numerical solutions analyze fluid flow patterns and temperature distributions, providing insights into heat exchange and thermal management. The research highlights the importance of hybrid nanofluids, notably those containing Al 2 O 3 and Cu in a water base, in improving overall heat transfer efficiency. The mathematical model accounts for laminar and incompressible fluid flow with a Prandtl number of Pr = 6.2, Lewis number Le = 10, and maximum 10 % concentration of hybrid nanoparticles. After transforming the governing equations into a non-dimensional form, the implicit finite difference method is used to solve them. The solution employs the in-house FORTRAN 90 code and compares its outcomes with the benchmark results. Various parameters, such as the Schmidt number (Sc = 1 to 10), volume fraction of nanoparticles ( ϕ = 0.0 to 0.1), wavy amplitude (A = 0.0 to 0.3), and N BT = (0.05 to 0.2), are investigated regarding temperature, velocity, local skin friction coefficient ( C f ) , local Nusselt number (Nu), streamlines, and isotherms. Elevated volume fraction generally decreases skin friction, increases temperature, and may reduce velocity. Meanwhile, higher skin friction, temperature, velocity, and local Nusselt numbers often correlate with elevated Schmidt numbers. Changes in amplitude and N BT affect skin friction, temperature, velocity, and local Nusselt numbers, providing information on the dynamics of fluid systems. For example, when the volume fraction (ϕ) increases from 0 to 0.1 at Y = 2, the temperature rises by 75 % , while the velocity gradually decreases by 11.11 % . This is in contrast to findings according to when the N BT rises from 0.05 to 0.2 at Y = 1. In this case, the temperature drops by 18.75 % , followed by a 9.68 % fall in fluid velocity. Understanding these interactions enhances comprehension of heat transfer and fluid dynamics. By investigating these interactions, we not only improve our understanding of heat transfer and fluid dynamics, but also open the door to new strategies for improving thermal systems and manufacturing procedures.

Investigation of thermal effects in bulk oxide chemical mechanical polishing

Bulk oxide polishing occupies a substantial portion of time to achieve surface planarization in semiconductor manufacturing. Recently, thermal management has emerged as a critical issue in the polishing process. Fundamental research on thermal effects in oxide film polishing is essential for optimizing both the thermal management system and the polishing process itself. Experiments indicate that friction force, significantly influenced by wafer and retainer ring pressures as well as slurry species, plays a major role in determining polishing temperature, more so than slurry flow rate. An important finding is the temperature-dependent behavior of slurry particles, which generally reduce in size and concentrate more at higher temperatures, with aggregation starting at around 80 °C. High-temperature slurry deteriorated pad properties but enhance oxide film surface hydrolyzation. During a 60-s polishing process, the slurry temperature exhibited the maximum removal rate at 60 °C for fumed silica polishing, while for calcined ceria, the highest removal rate was observed at 20 °C. Pad B at ambient temperature, having similar hardness to Pad A at 60 °C, reduced the oxide film removal rate by 31.82 % for fumed silica and 40.94 % for calcined ceria. This indicates that pad hardness has a more pronounced effect on polishing with calcined ceria slurry.

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 aimed towards 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 5,000. 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.

Numerical Evaluation and Artificial Neural Network (ANN) Model of the Photovoltaic Thermal (PVT) System with Different Nanofluids

Numerical Evaluation and Artificial Neural Network (ANN) Model of the Photovoltaic Thermal (PVT) System with Different Nanofluids