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Sharmin, Afsana. "EMBEDDED COOLING OF HIGH PERFORMANCE ICS USING NOVEL NANOSTRUCTURED THERMOELECTRICS." OpenSIUC, 2013. https://opensiuc.lib.siu.edu/theses/1308.
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AN ABSTRACT OF THE THESIS OF AFSANA SHARMIN, for the Master of Science degree in Electrical and Computer Engineering, presented on November 1, 2013, at Southern Illinois University Carbondale. TITLE: EMBEDDED COOLING OF HIGH PERFORMANCE ICS USING NOVEL NANOSTRUCTURED THERMOELECTRICS MAJOR PROFESSOR: Dr. Shaikh S. Ahmed Site specific thermoelectric cooling in semiconductor materials is among the most promising approaches for the mitigation of on-chip hot spots resulting from the decreasing feature sizes and faster switching speeds of electronic components. The efficient usage of thermoelectric devices for hotspot cooling requires investigation and appropriate properties such as higher figure of merit, integration of these devices with electronic package, remedy of various obstacles such as parasitic contact resistances. A simulation model has been developed to investigate the effect of steady state operation of nanowire based thermoelectric cooler devices on hot-spot cooling considering the effect of crucial thermal and electrical contact resistances. The results suggest that active hotspot cooling of as much as 23ºC with a high (~1,300W/cm2) heat flux for nanowire based Bi2Te3 thermoelectric cooler. It has been observed from the results that thermal and electrical contact resistances play a very crucial role in the performance of nanowire based thermoelectric cooling devices as high values of these resistances can significantly degrade the effect of Peltier cooling.
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Pieskä, Henrikki. "Performance evaluations of high-temperature cooling systems in Mediterranean climate." Licentiate thesis, KTH, Hållbara byggnader, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-289578.
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Cooling demand in Europe is predicted to grow 25-50% between 2020-2050. Meanwhile, the EU aims to lower the greenhouse gas emissions from its building stock by 60%. Therefore, it is essential to find solutions that can meet the growing cooling demand with less energy and integrate renewable energy sources. The goal of this thesis is to technically evaluatehigh-temperature cooling systems and their contributions to the targets mentioned above. The study was conducted using advanced building energy simulations and developing analytical methods. IDA Indoor Climate and Energy 4.8was selected as the simulation tool. The study is a part of GEOFIT project, and the used building physics and measurement data were based on one of the project pilots. The selected building is a representative office building that is a part of a three-building school complex. The building is located in Sant Cugat near Barcelona, in an area which has a typical Mediterranean climate. The simulated building model was validated using onsite measurement data. Two types of high-temperature cooling systems were studied: a radiant cooling system and an all-air cooling system. For the study, the systems were designed to create equal thermal comfort conditions, so that their energy and exergy use could be compared. In the studied case, the radiant cooling system was found to use 40% less energy and consume 85% less exergy than a conventional low-temperature all-air cooling system. It was also found that a passive geothermal radiant cooling system requires 66% less electricity for pumps and fans than a passive geothermal all-air cooling system. The results demonstrate that radiant cooling systems have the potential to lower exergy consumption in cooling applications thanks to the high supply temperature and that using water as a heat transfer medium is more efficient than using air.Kylningsefterfrågan i Europa förutses att växa 25-50% mellan 2020-2050. Samtidigt strävar EU efter att sänka utsläppen av växthusgaser från sina byggnader med 60%. Det är därför viktigt att hitta lösningar som kan tillgodose det växande kylbehovet med mindre energi och att integrera förnybara energikällor. Målet med denna avhandling är en teknisk evaluering av högtemperatur-kylsystem och deras bidrag till ovan nämnda mål. Studien genomfördes med avancerade simuleringar av byggnadsenergi och utvecklade analytiska metoder. IDA Indoor Climate and Energy 4.8 valdes som simuleringsverktyg. Studien är en del av GEOFIT-projektet och den använda byggnadsfysiken och mätdata baserades på en av projektpiloterna. Den valda byggnaden är en representativ kontorsbyggnad som ingår i ett skolbyggnad med tre byggnader. Byggnaden ligger i Sant Cugat nära Barcelona, i ett område som har ett typiskt medelhavsklimat. Den simulerade byggnadsmodellen validerades med hjälp av mätdata på plats. Två typer av högtemperatur-kylsystem studerades: ett strålande kylsystem och ett luftkylsystem. För studien designades systemen för att skapa lika termiska komfortförhållanden, så att deras energi och exergianvändning kunde jämföras. I det studerade fallet visade sig att det strålande kylsystemet använde 40% mindre energi och förbrukade 85% mindre exergi än ett konventionellt högtemperatur-kylsystem med låg temperatur. Man fann också att ett passivt geotermiskt strålkylsystem kräver 66% mindre el för pumpar och fläktar än ett passivt geotermiskt luftkylsystem. Resultaten visar att strålningskylsystem har potential att sänka exergiförbrukningen i kylapplikationer tack vare den höga framledningstemperaturen och att användning av vatten som värmeöverföringsmedium är effektivare än att använda luft.
QC 210204
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Zheng, Li. "Power distribution network modeling and microfluidic cooling for high-performance computing systems." Diss., Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/54449.
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A silicon interposer platform with microfluidic cooling is proposed for high-performance computing systems. The key components and technologies for the proposed platform, including electrical and fluidic microbumps, microfluidic vias and heat sinks, and simultaneous flip-chip bonding of the electrical and fluidic microbumps, are developed and demonstrated. Fine-pitch electrical microbumps of 25 µm diameter and 50 µm pitch, fluidic vias of 100 µm diameter, and annular-shaped fluidic microbumps of 150 µm inner diameter and 210 µm outer diameter were fabricated and bonded. Electrical and fluidic tests were conducted to verify the bonding results. Moreover, the thermal and signaling benefits of the proposed platform were evaluated based on thermal measurements and simulations, and signaling simulations. Compared to the conventional air cooling, significant reductions in system temperature and thermal coupling are achieved with the proposed platform. Moreover, the signaling performance is improved due to the reduced temperature, especially for long interconnects on the silicon interposer.
A numerical power distribution network (PDN) simulator is developed based on distributed circuit models for on-die power/ground grids, package- and board- level power/ground planes, and the finite difference method. The simulator enables power supply noise simulation, including IR-drop and simultaneous switching noise, for a full chip with multiple blocks of different power, decoupling capacitor, and power/ground pad densities. The distributed circuit model is further extended to include TSVs to enable simulations for 3D PDN. The integration of package- and board- level power/ground planes enables co-simulation of die-package-board PDN and exploration of new PDN configurations.
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JImenez, Lopez Carlos. "Performance analysis and validation of high-temperature cooling panels in passive geothermal system." Thesis, KTH, Hållbara byggnader, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-247915.
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High Temperature Cooling, HTC, is a thermal conditioning strategy, which aims to reducemixing and transfer heat losses. Cooling capacity strongly depends on heat transfer coefficientsand offers a great response and several advantages in terms of efficiency and sustainability.Among the advantages, there is evidence that HTC offers an increment of energy efficiency ofHVAC systems, provision of healthier and more comfortable indoor climate and provide widepotentials for the applications of renewable. This principle leads to a higher energy efficiency ofwater-based radiant cooling systems.This paper intends to focus on the research of the thermal capacity and performance of a newalternative. This is where Cooling Radiant Ceiling Panels, CRCP, becomes a major innovationwithin the sector and begin to take on certain relevance. The cooling capacity curve of thisparticular CRCP panels has been only measured in an idealized room environment according toDIN EN 14240. Thus, further studies of this key parameter through climate chamber testingand Computational Fluid Dynamics simulations, CFD, are necessary. CFD particularly focuseson fluids in motion, their behavior and their influences in complex processes such as heat transfer.The fluid motion can be described through fundamental mathematical equations and it isbecoming widely used within the building sector.Two different cases are going to be investigated. The first case will determine the mostoptimal peripheral gap to enhance cooling performance through Natural Convection, NC. Thisstudy states the existence of a peripheral gap around the panels has proven to be inefficientin terms of enhancing natural convection in the climate chamber. The second case is aboutcalculating the cooling capacity as a function of the internal heat loads. The cooling capacity ofthe CRCP panels followed an expected behavior. The R-squared factor of the linear regressionwas found to be 0.986, hence, it does not affect the performance of the CRCP panels dependingon the inclusion of the IHLs.This thesis provides the necessary information for the implementation of CRCP panels anddifferent possible operating environments, including considerations, limitations and recommendationsfor future implementation of this strategy.
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Ortéga, Benjamin. "HEV thermal management of high voltage battery with indirect air cooling and regarding customer performance." Thesis, KTH, Fordonsdynamik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-293365.
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The automotive environment is quickly evolving due to increasingly stringent environmentalstandards and the gradual reduction of the volume of diesel motorized vehicles. The volumes of electrifiedvehicles are thus constantly growing and are brought to be more and more present in our streets. Thiselectrification of vehicles involves new specifics issues compared to conventional vehicles, depending on thedifferent levels of electrification, which includes notably Hybrid Electric Vehicles.Hybridization in cars is characterized by the addition of a electrical traction and/or electrical generation systemin addition to the conventional thermal engine. However, if the complexity of vehicles with thermal tractioncomes essentially from the internal combustion engine and its efficiency which are sometimes complex tooptimize, the complexity of electric traction is expressed on the other hand at the level of the battery whichsupplies high voltage electricity. Indeed, while an electric machine offers high efficiency and an easy control,the high voltage battery contains many issues linked to a complex chemistry which must be controlled, andcan be subject to overheating.This overheating phenomenon is particularly an issue on HEV, which have smaller batteries than BEV and PHEVapplications for a comparable power demand. The conception of an efficient high-voltage battery coolingsystem is therefore essential in order to avoid any danger of damaging the system or potential fires linked tothe overheating of the battery. The air cooling solution is the most common, but this could change with thenew standard of the Electric Vehicle Safety Global Technical Regulation (EVS-GTR) applicable in 2021prohibiting the rejection of the cooling air that was in contact with the battery cells inside the passengercompartment. Is this solution able to adapt in order to remain competitive with the water or air conditioningcooling solutions? This study's purpose is to bring an answer to this issue.
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Nasir, Shakeel. "Showerhead Film Cooling Performance of a Turbine Vane at High Freestream Turbulence in a Transonic Cascade." Diss., Virginia Tech, 2007. http://hdl.handle.net/10919/28560.
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One way to increase cycle efficiency of a gas turbine engine is to operate at higher turbine inlet temperature (TIT). In most engines, the turbine inlet temperatures have increased to be well above the metallurgical limit of engine components. Film cooling of gas turbine components (blades and vanes) is a widely used technique that allows higher turbine inlet temperatures by maintaining material temperatures within acceptable limits. In this cooling method, air is extracted from the compressor and forced through internal cooling passages within turbine blades and vanes before being ejected through discrete cooling holes on the surfaces of these airfoils. The air leaving these cooling holes forms a film of cool air on the component surface which protects the part from hot gas exiting the combustor.
Design optimization of the airfoil film cooling system on an engine scale is a key as increasing the amount of coolant supplied yields a cooler airfoil that will last longer, but decreases engine core flowâ diminishing overall cycle efficiency. Interestingly, when contemplating the physics of film cooling, optimization is also a key to developing an effective design. The film cooling process is shown to be a complex function of at least two important mechanisms: Increasing the amount of coolant injected reduces the driving temperature (adiabatic wall temperature) of convective heat transferâ reducing heat load to the airfoil, but coolant injection also disturbs boundary layer and augments convective heat transfer coefficient due to local increase in freestream turbulence.
Accurate numerical modeling of airfoil film cooling performance is a challenge as it is complicated by several factors such as film cooling hole shape, coolant-to-freestream blowing ratio, coolant-to-freestream momentum ratio, surface curvature, approaching boundary layer state, Reynolds number, Mach number, combustor-generated high freestream turbulence, turbulence length scale, and secondary flows just to name a few. Until computational methods are able to accurately simulate these factors affecting film cooling performance, experimental studies are required to assist engineers in designing effective film cooling schemes.
The unique contribution of this research work is to experimentally and numerically investigate the effects of coolant injection rate or blowing ratio and exit Reynolds number/Mach number on the film cooling performance of a showerhead film cooled first stage turbine vane at high freestream turbulence (Tu = 16%) and engine representative exit flow conditions. The vane was arranged in a two-dimensional, linear cascade in a heated, transonic, blow-down wind tunnel. The same facility was also used to conduct experimental and numerical study of the effects of freestream turbulence, and Reynolds number on smooth (without film cooling holes) turbine blade and vane heat transfer at engine representative exit flow conditions. The showerhead film cooled vane was instrumented with single-sided platinum thin film gauges to experimentally determine the Nusselt number and film cooling effectiveness distributions over the surface from a single transient-temperature run. Showerhead film cooling was found to augment Nusselt number and reduce adiabatic wall temperature downstream of injection. The adiabatic effectiveness trend on the suction surface was also found to be influenced by a favorable pressure gradient due to Mach number and boundary layer transition region at all blowing ratio and exit Mach number conditions.
The experimental study was also complimented with a 3-D CFD effort to calculate and explain adiabatic film cooling effectiveness and Nusselt number distributions downstream of the showerhead film cooling rows of a turbine vane at high freestream turbulence (Tu = 16%) and engine design exit flow condition (Mex = 0.76). The research work presents a new three-simulations technique to calculate vane surface recovery temperature, adiabatic wall temperature, and surface Nusselt number to completely characterize film cooling performance in a high speed flow. The RANS based v2-f turbulence model was used in all numerical calculations. CFD calculations performed with experiment-matched boundary conditions showed an overall good trend agreement with experimental adiabatic film cooling effectiveness and Nusselt number distributions downstream of the showerhead film cooling rows of the vane.Ph. D.
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Meinert, Jens. "Transport und Speicherung von Energie." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2008. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1200578310250-97598.
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Neben der Umwandlung von Energie gehören deren Transport und Speicherung zu den wichtigsten ingenieurwissenschaftlichen Problemfeldern. Die optimale Ausnutzung beider Mechanismen könnte entscheidend zur Überwindung der häufig existierenden örtlichen und zeitlichen Diskrepanz zwischen Notwendigkeit und Verfügbarkeit energetischer Ressourcen beitragen. Dies steht im Mittelpunkt von Forschungsarbeiten am Graduiertenkolleg Hochleistungsbauteilkühlung und der gleichnamigen Juniorprofessur am Institut für Thermodynamik und Technische Gebäudeausrüstung der TU Dresden. Sie beschäftigen sich zum einen mit der Optimierung von Wärmetransportmechanismen vor allem zur Kühlung und zum anderen mit der Speicherung stoffgebundener Energie. Die notwendigen strömungs- und wärmetechnischen Untersuchungen sind sowohl auf experimentellem als auch auf numerischem Gebiet angesiedeltAlongside energy conversion, the transfer and storage of energy represent two of the most important research areas in the field of engineering sciences. The optimal use of both mechanisms could make a significant contribution to overcoming the frequently encountered local and temporal discrepancy between demand and the availability of energy resources. The research within the graduate college on high-performance cooling at the Institut für Thermodynamik und Technische Gebäudeausrüstung of TU Dresden, together with that of a corresponding junior professorship, is focussed on the optimisation of heat transfer processes for cooling purposes and for the storage of thermal energy. The necessary investigations of flow and heat transfer are based on experimental as well as numerical methods
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Mohammed, Awaizulla Shareef. "Investigation of Immersion Cooled ARM-Based Computer Clusters for Low-Cost, High-Performance Computing." Thesis, University of North Texas, 2017. https://digital.library.unt.edu/ark:/67531/metadc1011866/.
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This study aimed to investigate performance of ARM-based computer clusters using two-phase immersion cooling approach, and demonstrate its potential benefits over the air-based natural and forced convection approaches. ARM-based clusters were created using Raspberry Pi model 2 and 3, a commodity-level, single-board computer. Immersion cooling mode utilized two types of dielectric liquids, HFE-7000 and HFE-7100. Experiments involved running benchmarking tests Sysbench high performance linpack (HPL), and the combination of both in order to quantify the key parameters of device junction temperature, frequency, execution time, computing performance, and energy consumption. Results indicated that the device core temperature has direct effects on the computing performance and energy consumption. In the reference, natural convection cooling mode, as the temperature raised, the cluster started to decease its operating frequency to save the internal cores from damage. This resulted in decline of computing performance and increase of execution time, further leading to increase of energy consumption. In more extreme cases, performance of the cluster dropped by 4X, while the energy consumption increased by 220%. This study therefore demonstrated that two-phase immersion cooling method with its near-isothermal, high heat transfer capability would enable fast, energy efficient, and reliable operation, particularly benefiting high performance computing applications where conventional air-based cooling methods would fail.
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Newman, Andrew Samuel. "Performance of a Showerhead and Shaped Hole Film Cooled Vane at High Freestream Turbulence and Transonic Conditions." Thesis, Virginia Tech, 2010. http://hdl.handle.net/10919/76778.
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An experimental study was performed to measure surface Nusselt number and film cooling effectiveness on a film cooled first stage nozzle guide vane using a transient thin film gauge (TFG) technique. The information presented attempts to further characterize the performance of shaped hole film cooling by taking measurements on a row of shaped holes downstream of leading edge showerhead injection on both the pressure and suction surfaces (hereafter PS and SS) of a 1st stage NGV. Tests were performed at engine representative Mach and Reynolds numbers and high inlet turbulence intensity and large length scale at the Virginia Tech Transonic Cascade facility. Three exit Mach/Reynolds number conditions were tested: 1.0/1,400,000; 0.85/1,150,000; and 0.60/850,000 where Reynolds number is based on exit conditions and vane chord. At Mach/Reynolds numbers of 1.0/1,450,000 and 0.85/1,150,000 three blowing ratio conditions were tested: BR = 1.0, 1.5, and 2.0. At a Mach/Reynolds number of 0.60/850,000, two blowing ratio conditions were tested: BR = 1.5 and 2.0. All tests were performed at inlet turbulence intensity of 12% and length scale normalized by leading edge diameter of 0.28. Film cooling effectiveness and heat transfer results compared well with previously published data, showing a marked effectiveness improvement (up to 2.5x) over the showerhead only NGV and agreement with published showerhead-shaped hole data. NHFR was shown to increase substantially (average 2.6x increase) with the addition of shaped holes, with only a small increase (average 1.6x increase) in required coolant mass flow. Heat transfer and effectiveness augmentation with increasing blowing ratio was shown on the pressure side, however the suction side was shown to be less sensitive to changing blowing ratio. Boundary layer transition location was shown to be within a consistent region on the suction side regardless of blowing ratio and exit Mach number.Master of Science
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Franceschelli, Luca. "Cooling Performance Analysis and Design of an Instrumented Radiator in a MotoGP Wind Tunnel Model." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.
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The present thesis work was developed in collaboration with the Ducati Corse Aerodynamic Department. It is focused on the measurement system employed on the MotoGP Wind Tunnel model in order to evaluate the cooling performances at the radiators.
As first, an analysis of the current methodology is conducted. Based on the arrangement of hybrid-Kiel probes behind the radiators, it was observed that an improvement in the calibration procedure is required in order to account for inter-probe and support frame interference. Furthermore, a correlation process with the CFD simulation was carried out. A good agreement in trend with CFD results was displayed, despite a low accuracy. The need for higher spatial resolution was stated.
In order to update the CFD implementation of the actual water radiator, the latter has been characterized in terms of pressure drop on a dedicate radiator test bench, provided by Dallara Automobili. A suitable convergent frame has been designed for the purpose.
Finally, a new methodology for cooling performance evaluation was developed and calibrated. The method exploits a set of static and Kiel probes in a dummy radiator core. An honeycomb structure and a perforated plate are implemented to reproduce the real radiator behaviour.
Experiments have been performed with half-radiator equipped with the new set up and the other half instrumented with Pitot tubes, showing good agreement between the two probe-types.
A set of plates have been characterized. It allowed also to highlight the relevance of the solid part distribution - and related holes' diameter - on the pressure drop and the effect on the measured pressures from the probes.
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Steiert, Christoph, Juliane Weber, Alexander Galant, Janine Glänzel, and Jürgen Weber. "Fluid-thermal co-simulation for a high performance concrete machine frame." Technische Universität Dresden, 2020. https://tud.qucosa.de/id/qucosa%3A71161.
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Thermo-elastic errors are one of the main drivers for reduced quality of workpieces in machining. Cooling systems can prevent these errors and improve quality. The paper describes a simulation method that takes into account both the temperature field of a machine tool frame and the fluid cooling system. Such simulations can help to improve the thermal stability of the machine tool frame.
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Kendrick, John Thomas. "Design of High-Performance, Dual-Motor Liquid-Cooled, Linear Series Elastic Actuators for a Self-Balancing Exoskeleton." Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/83236.
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As a valuable asset in human augmentation and medical rehabilitation, exoskeletons have become a major area for research and development. They have shown themselves to be effective tools for training and rehabilitation of individuals suffering from limited mobility. However, most exoskeletons are not capable of balancing without the assistance of crutches from the user. Leveraging technology and techniques developed for force controlled humanoid robots, a project was undertaken to develop a fully self-balancing, compliant lower-body robotic exoskeleton. Due to their many beneficial features, series elastic actuators were utilized to power the joints on the exoskeleton. This thesis details the development of four linear series elastic actuators (LSEA) as part of this project. All 12-degrees of freedom will be powered by one of these four LSEA's. Actuator requirements were developed by examining human gait data and three robot-walking simulations. These four walking scenarios were synthesized into one set of power requirements for actuator development. Using these requirements, analytical models were developed to perform component trade studies and predict the performance of the actuator. These actuators utilize high-efficacy components, parallel electric motors, and liquid cooling to attain high power-to-weight ratios, while maintaining a small lightweight design. These analyses and trade studies have resulted in the design of a dual-motor liquid-cooled actuator capable of producing a peak force 8500N with a maximum travel speed of 0.267m/s, and three different single-motor actuators capable of producing forces up to 2450N continuously, with a maximum travel speeds up to 0.767m/s.Master of Science
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O'Dowd, Devin Owen. "Aero-thermal performance of transonic high-pressure turbine blade tips." Thesis, University of Oxford, 2010. http://ora.ox.ac.uk/objects/uuid:e7b8e7d0-4973-4757-b4df-415723e7562f.
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Bazile, Alban. "Formulation éléments finis variationnelle adaptative et calcul massivement parallèle pour l’aérothermique industrielle." Thesis, Paris Sciences et Lettres (ComUE), 2019. http://www.theses.fr/2019PSLEM008/document.
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Considérant les récents progrès dans le domaine du Calcul Haute Performance, le but ultime des constructeurs aéronautiques tels que Safran Aircraft Engines (SAE) sera de simuler un moteur d'avion complet, à l'échelle 1, utilisant la mécanique des fluides numérique d'ici 2030. Le but de cette thèse de doctorat est donc de donner une contribution scientifique à ce projet. En effet, ce travail est consacré au développement d'une méthode élément finis variationnelle adaptative visant à améliorer la simulation aérothermique du refroidissement des aubes de turbine. Plus précisément, notre objectif est de développer une nouvelle méthode d'adaptation de maillage multi-échelle adaptée à la résolution des transferts thermiques hautement convectifs dans les écoulements turbulents. Pour cela, nous proposons un contrôle hiérarchique des erreurs, basé sur des estimateurs d'erreur sous-échelle de type VMS. La première contribution de ce travail est de proposer une nouvelle méthode d'adaptation de maillage isotrope basée sur ces estimateurs d'erreur sous-échelle. La seconde contribution est de combiner (i) un indicateur d'erreur d'interpolation anisotrope avec (ii) un estimateur d'erreur sous-échelle pour l'adaptation anisotrope de maillage. Les résultats sur des cas analytiques 2D et 3D montrent que la méthode d'adaptation de maillage multi-échelle proposée nous permet d'obtenir des solutions hautement précises utilisant moins d'éléments, en comparaison avec les méthodes d'adaptation de maillage traditionnelles. Enfin, nous proposons dans cette thèse une description des méthodes de calcul parallèle dans Cimlib-CFD. Ensuite, nous présentons les deux systèmes de calcul utilisés pendant le doctorat. L'un d'eux est, en particulier, le super-calculateur GENCI Occigen II qui nous a permit de produire des résultats numériques sur un cas d'aube de turbine complète composé de 39 trous en utilisant des calculs massivement parallèlesBy 2030, considering the progress of HPC, aerospace manufacturers like Safran Aircraft Engines (SAE), hope to be able to simulate a whole aircraft engine, at full scale, using Computational Fluid Dynamic (CFD). The goal of this PhD thesis is to bring a scientific contribution to this research framework. Indeed, the present work is devoted to the development of a variational adaptive finite element method allowing to improve the aerothermal simulations related to the turbine blade cooling. More precisely, our goal is to develop a new multiscale mesh adaptation technique, well suited to the resolution of highly convective heat transfers in turbulent flows. To do so, we propose a hierarchical control of errors based on recently developed subscales VMS error estimators. The first contribution of this work is then to propose a new isotropic mesh adaptation technique based on the previous error estimates. The second contribution is to combine both (i) the coarse scales interpolation error indicator and (ii) the subscales error estimator for anisotropic mesh adaptation. The results on analytic 2D and 3D benchmarks show that the proposed multiscale mesh adaptation technique allows obtaining highly precise solutions with much less elements in comparison with other mesh adaptation techniques. Finally, we propose in this thesis a description of the parallel software capabilities of Cimlib-CFD. Then, we present the two hardware systems used during this PhD thesis. The first one is the lab's cluster allowing the development of numerical methods. The second one however, is the GENCI Occigen II supercomputer which allows producing numerical results using massively parallel computations. In particular, we present a more realistic industrial concerning the cooling of a complete turbine vane composed by 39 holes
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Virdi, Amandeep Singh. "Aero-thermal performance and enhanced internal cooling of unshrouded turbine blade tips." Thesis, University of Oxford, 2015. https://ora.ox.ac.uk/objects/uuid:62c3e94a-a1ff-47a8-bb81-e870b0013f11.
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The tips of unshrouded, high-pressure turbine blades are prone to significantly high heat loads. The gap between the tip and over-tip casing is the root cause of undesirable over-tip leakage flow that is directly responsible for high thermal material degradation and is a major source of aerodynamic loss within a turbine. Both must be minimised for the safe working and improved performance of future gas-turbines. A joint experimental and numerical study is presented to understand and characterise the heat transfer and aerodynamics of unshrouded blade tips. The investigation is undertaken with the use of a squealer or cavity tip design, known for offering the best overall compromise between the tip aerodynamics, heat transfer and mechanical stress. Since there is a lack of understanding of these tips at engine-realistic conditions, the present study comprises of a detailed analysis using a high-speed linear cascade and computational simulations. The aero-thermal performance is studied to provide a better insight into the behaviour of squealer tips, the effects of casing movement and tip cooling. The linear cascade environment has proved beneficial for its offering of spatially-resolved data maps and its ability to validate computational results. Due to the unknown tip gap height within an entire engine cycle, the effects of gap height are assessed. The squealer's aero-thermal performance has been shown to be linked with the gap height, and qualitative different trends in heat transfer are established between low-speed and high-speed tip flow regimes. To the author's knowledge, the present work is the first of its kind, providing comprehensive aero-thermal experimental research and a dataset for a squealer tip at engine-representative transonic conditions. It is also unique in terms of conducting direct and systematic validations of a major industrial computational fluid dynamics method for aero-thermal performance prediction of squealer tips at enginerepresentative transonic conditions. Finally, after recognising the highest heat loads are found on the squealer rims, a novel shaped squealer tip has been investigated to help improve the thermal performance of the squealer with a goal to improve its durability. It has been discovered that a seven percent reduction in tip temperature can be achieved through incorporating a shaped squealer and maximising the internal cooling performance.
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Crosatti, Lorenzo. "Experimental and numerical investigation of the thermal performance of gas-cooled divertor modules." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/24717.
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Thesis (Ph.D.)--Mechanical Engineering, Georgia Institute of Technology, 2008.Committee Co-Chair: Minami Yoda, Co-Advisor; Committee Co-Chair: Said I. Abdel-Khalik; Committee Member: Donald R. Webster; Committee Member: Narayanan M. Komerath; Committee Member: S. Mostafa Ghiaasiaan; Committee Member: Yogendra Joshi
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Villafañe, Roca Laura. "Experimental Aerothermal Performance of Turbofan Bypass Flow Heat Exchangers." Doctoral thesis, Universitat Politècnica de València, 2014. http://hdl.handle.net/10251/34774.
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The path to future aero-engines with more efficient engine architectures requires advanced
thermal management technologies to handle the demand of refrigeration and lubrication. Oil
systems, holding a double function as lubricant and coolant circuits, require supplemental
cooling sources to the conventional fuel based cooling systems as the current oil thermal
capacity becomes saturated with future engine developments. The present research focuses on
air/oil coolers, which geometrical characteristics and location are designed to minimize
aerodynamic effects while maximizing the thermal exchange. The heat exchangers composed
of parallel fins are integrated at the inner wall of the secondary duct of a turbofan. The
analysis of the interaction between the three-dimensional high velocity bypass flow and the
heat exchangers is essential to evaluate and optimize the aero-thermodynamic performances,
and to provide data for engine modeling. The objectives of this research are the development
of engine testing methods alternative to flight testing, and the characterization of the
aerothermal behavior of different finned heat exchanger configurations.
A new blow-down wind tunnel test facility was specifically designed to replicate the engine
bypass flow in the region of the splitter. The annular sector type test section consists on a
complex 3D geometry, as a result of three dimensional numerical flow simulations. The flow
evolves over the splitter duplicated at real scale, guided by helicoidally shaped lateral walls.
The development of measurement techniques for the present application involved the design
of instrumentation, testing procedures and data reduction methods. Detailed studies were
focused on multi-hole and fine wire thermocouple probes.
Two types of test campaigns were performed dedicated to: flow measurements along the test
section for different test configurations, i.e. in the absence of heat exchangers and in the
presence of different heat exchanger geometries, and heat transfer measurements on the heat
exchanger. As a result contours of flow velocity, angular distributions, total and static
pressures, temperatures and turbulence intensities, at different bypass duct axial positions, as
well as wall pressures along the test section, were obtained. The analysis of the flow
development along the test section allowed the understanding of the different flow behaviors
for each test configuration. Comparison of flow variables at each measurement plane
permitted quantifying and contrasting the different flow disturbances. Detailed analyses of the
flow downstream of the heat exchangers were assessed to characterize the flow in the fins¿
wake region. The aerodynamic performance of each heat exchanger configuration was
evaluated in terms of non dimensional pressure losses. Fins convective heat transfer
characteristics were derived from the infrared fin surface temperature measurements through a
new methodology based on inverse heat transfer methods coupled with conductive heat flux
models. The experimental characterization permitted to evaluate the cooling capacity of the
investigated type of heat exchangers for the design operational conditions. Finally, the
thermal efficiency of the heat exchanger at different points of the flight envelope during a
typical commercial mission was estimated by extrapolating the convective properties of the
flow to flight conditions.Villafañe Roca, L. (2013). Experimental Aerothermal Performance of Turbofan Bypass Flow Heat Exchangers [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/34774
TESIS
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Shih, Yu-Li, and 施雨利. "Rapid-ventilation energy-saving high- performance heating/cooling air conditioner." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/40396048691090530443.
Full textAbstract:
碩士崑山科技大學
機械工程研究所
101
Conventional cold/hot-function heat-pump air conditioners have been used four-way valve to generate cooling or heating effect by changing the refrigerant flow-directions. The heat exchanger of indoor or outdoor is used as a condenser or evaporator. The surface-area of the condenser must equal to about 1.3 times to that of evaporator to match energy balance. Thus, while the air conditioner is designed mainly in cold function, the outdoor heat exchanger must be greater than the indoor heat exchanger; the machine will be with good cold-function efficient in hot days, but not for the hot-function efficient in cold days. On the contrary, while the air conditioner is designed mainly in hot function, the outdoor heat exchanger must be less than the indoor heat exchanger; the machine will be with good hot-function efficient in cold days, but not for the cold-function efficient in hot days. Moreover, if one wants to change the cold/hot function into hot/cold function during the machine in operation, the pressure difference on both sides of the four-way valve is about more than 10 times the atmospheric, the cold/hot function switch has been frequently damaged by excessive force.Furthermore, the ventilation-function of window-type air conditioner is very poor. For energy saving, all the windows and doors are always closed when air conditioner is in use. It will lead to poor indoor air quality, especially while there are many people in a classroom or office. The year 2012 master thesis "variable damper multi-function heat-pump type air conditioner" completed by senior Te-Kuo Chang, pinpointed the above shortcomings, it used variable damper to generate high-performance heating/cooling functions. It also can be timed for a few minutes using the rapid ventilation to maintain the health of people, is a revolutionary creative works. It is pity lack of enough time to let the damper transformation to reach reliable action, it is easy to fault. This thesis “Rapid-ventilation high-performance energy-saving hot/cold air conditioner” takes over Te-Kuo Chang’s great ideas and the completion by using a reliable two-way conversion motor, steel chain and contactor chain stopper to control the dampers actions, and the upper and lower dampers are controlled at different locations to achieve various functions by a reliable chip controller. The various functions includes:（1） high-performance cooling function （2） a few minutes per hour timing ventilation during the operation of cooling function （3） high performance of heating function （4） a few minutes per hour timing ventilation during the operation of heating function （5） in situation of outside air temperature with 20 ~ 25 ℃ stopping the compressor and only using fan ventilation to reach energy-saving more than 93% （6） in situation of outside air temperature with 20 ~ 25 ℃ stopping the compressor and only using a single-fan quiet ventilation to reach energy-saving more than 96% （7） in situation of temperature-difference between outside air and evaporator is below 8 ℃, the heat-pump heating function is not suitable applied, an electric heater is installed in front of or behind the condenser; in such situation, the compressor and evaporator fan are switched off, and the electric heater and condenser fan are switched on to produce electric heating in very cold weather( 8 ) a few minutes per hour timing ventilation during the operation of electrical heating function .There is no any more energy-saving effect in above situation, but let machine become an all-weather one, thus it can be suitable for most region of the world. Therefore, the idle rate of this design will be very low, and it should be widely welcomed by users around the world. From this, the cold air is ever generated by the smaller evaporator and hot air is ever generated by the larger condenser. Thus, both hot and cold functions are with high performances. Thus, with these outstanding features beyond the current cold/hot-function heat-pump air conditioners, and with about the same cost as present air conditioner, this product has the market potential to replace all the present window-type air conditioners after its commercialization by technology transfer domestic well-known appliance maker. It is very optimistic about the prospects.
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Kao, Jian-Wei, and 高健維. "Performance improvement of cooling systems for high precision machine tools." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/91439394082690351537.
Full textAbstract:
碩士國立勤益科技大學
冷凍空調系
98
Precise-manufacturing facilies, which emphasize accurate and stable machining of the working components cannot function properly without appropriate and precise cooling. The dramatic variation of heat load during high-accuracy and high-speed need a critical control of coolant temperature and energy-saving control strategy as well. In this study, the performance of a machine tool cooler system was evaluated by first law and second law of thermodynamics to identify the possible improvement for system components. Besides, the investigation of hot-gas by-pass control scheme with different delay time for control valves were conducted to examine the temperature control control accuracy. Another PID and Smith control algorithm along with system identification approach were also compared to examine the temperature control accuracy and the power consumption of the system as well. The experimental results revealed the machine tool cooler system with DC inverter driven and Smith control algorithm would lead to better temperature accuracy under different loading and ambient conditions. The comprehensive studies on improving the system performance, tempereature accuracy and energy-saving potential will stimulate the robust investigation for a cooler system specific for high-speed machining application.
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Liu, Yi-Feng, and 劉毅鋒. "Numerical Study of Cooling Performance of High Power LED Fish-Lamp." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/59533798890584956598.
Full textAbstract:
碩士國立臺灣海洋大學
機械與機電工程學系
103
In the lights fishery, the ship energy consumes a proportion to has the mainest of equipment for gather a fish light, the tradition gathers the fish lamp existence purple outside and only, surface heat and high energy-consuming problem, as adoption high the power give out light diode(LED) to improve the weakness of traditional lamp. The tradition gathers a fish lamp the center shine on a degree about is a 2500~3000 Lux, in the bright degree of not lost all lamp, Certanly will adopt Gao power LED light to reach it illuminates of need, but will spread out LED over the hot etc. problem. This research aims at higher - first power LED eliminate heat hot system field analysis, by computing fluid mechanics software Icepak imitate the analysis. The applied limited physical volume method(Finite-volume method) will dominate the equation exploitation control physical volume integral method(Control Volume Integration Approach) and differ the equation convert of the dominating of integral type to divide into a method for the finite, will be partial to the differential equation discrete to turn to solve the problems, such as field and thermal conduction...etc. of the 3D steady state, streaming and imitate its streaming field variety and temperature to distribute the condition. Try to calculate by average illumination formula again, with actual illumination compare to after, change its angle and irradiation area, observation change LED to gather a fish lamp can reach the illumination of gathering the fish lamp need. Analyze the result to know while analyzing in the single module, effectively change higher - power LED chip to carry the board, electric circuit substrate and heat dissipation interface material, again match to eliminate heat a fin slice to down suggest a little bit as a result with traditional LED light, the chip temperature can descend 32.7% around. For saving cost expense and weight of lamp, this research adopts high power LED of modularity to gather a fish lamp and carries on the single module many mold alignments and lamp to open the hole test and display to adopt 15 modes that module lamp opens the hole B as effect of the best emulations as a result, chip's maximum temperature the degree is just in 78.5 ℃ . Adopt this LED to gather a fish lamp it the total wattage is a 225 Watts, gather a fish lamp to try to calculate its illumination by 6 LEDs, center's biggest illumination can reach to a 2500 Lux, be able to replace the tradition to gather a fish lamp.
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Lu, Tsung-wei, and 呂宗蔚. "Experimental Analysis of Heat Transform and Thermal Performance for High Power LED Cooling System." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/83810085883343242504.
Full textAbstract:
碩士國立成功大學
工程科學系碩博士班
95
High power LED is an illuminating light source of environmental protection, which can save more power and have longer life than the traditional light source. However, the LED is a lighting component of high heat generation, producing much larger heat than the traditional LED under high illumination. Based on the conversion efficiency, the incandescent light bulb of 100 W has 12% heat dissipation, 83% infrared radiation and 5 % visible light. The LED has 15%~30% visible light and heat generated from the remainder. Because of the small LED package and the mold-filling plastic effect, the heat produced by lighting the LED is accumulated around the PN junction, which leads to the decreases of luminance and life, the drift of wavelength and too high temperature. Due to uneven thermal expansion coefficients in the LED, large enough thermal stresses caused by the high temperature result in the LED damage. Consequently, how to improve the heat dissipation becomes an important issue in increasing the efficiency of the LED. In this experimental study, the Taguchi design method is used to investigate the effects of the operating variables of heat dissipation modules applied to the 1W, 3W and 5W high power LEDs, incorporated with the efficiencies of heat dissipation and illumination. It is expected that the results of this work can reach a certain level of statistical analysis and obtain the optimum designed parameters of the heat dissipation module. The results can help us to further understand the heat-dissipated performance of high power LED. It is also anticipated that the conclusions of this study can assist in solving the problem of high heat generation of the current and future LEDs.
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Chen, Zhi-Yu, and 陳治宇. "A Study on Cutting Performance under Different Cooling/Lubrication Conditions for Glass-Substrate High-Speed Milling." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/72c632.
Full textAbstract:
碩士國立虎尾科技大學
機械與電腦輔助工程系碩士班
101
In the recent year, the glass substrate has become gradually the most important material of the development in the information technology enterprise, its demanding quantity is increasing higher and higher, the quality of various processing have been requested more severer. For the time being, the enterprise of glass processing is mainly on cutting and edge seaming, the process flow is complicated and the cost is higher, therefore , the important topics of the current processing technology are seeking for the breakthrough of short process and the efficient cost saving . Because the glass possesses the quality of high intensity, high stiffness and low thermal conductivity, it is easy to make the cutting tool have the fast abrasion in the processing period and have imperfections like cracks and edge/corner collapse on the processing surface. To improve the above problems, the high rotation speed and low cutting depth and cooling fluild are employed in this study, also collocates the suitable feed rate and proceed the side milling/cutting, control the tough and brittle milling/cutting transformation model hopefully, thus, improve the processing efficiency of the glass substrate. The study employs large and medium water- soluble cutting fluid and green Production technique MQL and uses the diamond Tungsten Carbide (WC) cutting tool to proceed the milling/cutting experiment of the glass substrate. During the milling/cutting experiment, dynamometer and spectrum analyzer are employed to monitor the cutting force and vibration quantity, respectively. Also, observing the quality of edge surface of glass and the abrasion of cutting tool under different experiment parameters by tool-microscope off-line. The experimental data are analyzed under numerical analysis. Results show that the comparison between the traditional medium quantity of pouring wet milling/cutting and MQL, large quantity of pouring wet milling/cutting provide a good quenching effect on processing zone, thus, reduce the abrasion of the cutting tool and contribute to lower the cutting force. Observing from the cutting dynamic vibration quantity reveals that adding the water- soluble cutting fluid will contribute to improve and lower the cutting vibration and provide the stable action of cutting. Another observing from the damage of the raw material edge reveals that the better surface quality of the glass edge is obtained under high cutting speed, low feed rate and shallow path cutting. Adding the water- soluble cutting fluid can lower effectively the large amount of heat which is generated in the processing period of the glass surface. The high temperature difference between the surface and the inner layer of the glass is avoided, thus, the internal stress of the glass increases and over the limited intensity of the glass itself, then, leads to the break of the glass. Observing from the abrasion quantity of the cutting tool reveals that adding the water- soluble cutting fluid in the milling/cutting period, when increasing the cutting depth, the apparent dent damage will appear on the abdomen part of the cutting tool as the feed rate is increasing. Applying the MQL processing will make the cutting tool collapse the edge and shell off on its front end. Making a comprehensive survey of all the performance of milling/cutting, raising the cutting speed, lowering both of the cutting depth and the feed rate will reduce the occurrence of damage of glass substrate edge effectively, upgrade the cutting tool life and obtain the better quality of edge surface.
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Lin, Shin-yi, and 林欣怡. "A study for the heat sink parameters on the cooling performance of a high power LED projector." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/38367280307708901166.
Full textAbstract:
碩士國立中山大學
機械與機電工程學系研究所
99
Current high power LEDs are used popularly, energy saving can be achieved if the heat transfer performance of a high power LED is increased. Numerical analysis is carried out herein to study the parameters effect on the cooling performance for the heat sinks of the LED projector. The parameters include fin spacing, fin depth, fin thickness, base thickness and flow speed. The numerical results reveal that the parameters of the heat sinks significantly affects the average Nusselt Number. The results of this study can provide design references for LED projector.
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Chen, Kuan-Cheng, and 陳冠丞. "Experimental studies on High Power Modules for the improvement of the thermal performance using liquid cooling methods." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/45476664971759285061.
Full textAbstract:
碩士國立交通大學
機械工程系所
102
In this study, the performance of liquid heat sinks using the copper foams and macrochannel applicable for electrical car for enhanced heat transfer is investigated experimentally. A total of 3 different pore density copper foams are made and arranged in a water-cooled cold plate. Test results indicate that with the presence of copper foam may lead to an appreciable increase in the pressure drop but it also provides a considerable heat transfer augmentation due to its unique dispersion characteristics. By placing high pore density copper foams at the inlet, the water velocity profile becomes uniform so that temperature distribution is better. This is because the high pore density copper foams have high resistance to spread the working fluid evenly. Seven distinctive test sections have been examined. The results reveal that the arrangements which followed by medium and low density pore density foams with high pore density copper foams can facilitate a more uniform temperature distribution of the cold plate. The experimentally measured results show that the thermal resistances of copper foams heat sinks are better than plate heat sinks about 44%-62%. A total of 4 different macrochannel heat sinks are arranged in a water-cooled cold plate, including a general parallel plate design, separated for sectional design, a block arrangement and a trapezoidal macrochannel heat sink. The pressure drop of separated for sectional design, block and a trapezoidal type are lower than the general parallel type. Under the same pumping power, the block type has the lowest thermal resistance which is about 30%-39% lower than plate heat sink.
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Zochowski, Thomas. "Effect of hand cooling on thermal and psychophysical strain and performance during high intensity intermittent training of elite swimmers." Thesis, 2006. http://hdl.handle.net/1828/2097.
Full textAbstract:
The purpose of the present study was to determine the effects of using intermittent hand cooling during high intensity, intermittent training on measures of thermoregulatory, performance and psychophysical variables in elite level swimmers in warm pools (30.50.5°C). Following a standard warm-up, ten male swimmers (20.3±3.2 yrs) were instructed to maintain the fastest average 100m time for an 8x 100m freestyle swimming set separated in a cool pool (CP), warm pool with cooling (WPC), and warm pool with no-cooling (WPNC). Time at 50m and 100m, core temperature (Tc), and heart rate (HR), as well as the rate of perceived exertion (RPE), thermal comfort (ThC) and thermal sensation (ThS) were recorded following each repetition. Participants were cooled during the 90 second rest interval between repetitions using the Rapid Thermal Exchange (RTX) [AVAcore Technologies Inc., Ann Arbor, MI]. There was a significant increase in performance when comparing the second 50m split time (1.16 ± 1.58s ) and 100m time (1.50 ± 1.98s) for the final repetition in the WPC condition compared to the final repetition in the WPNC condition (p<0.05). FIR, ThC and ThS were lower in the CP condition than the WPC and WPNC conditions (p<0.05). There was no significant difference in Tc and RPE between conditions. It was concluded that the results may be due to a placebo effect and at this time there appears no physiological or psychophysical advantage in using the RTX during high intensity, intermittent training of elite swimmers.
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Udakeri, Ravi. "Comparison of cooling performance of overhead and underfloor supply with rear door heat exchanger in high density data center clusters." 2008. http://hdl.handle.net/10106/1082.
Full text
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Shen, Yi-tang, and 沈邑蓎. "Practicing “Cooling Conflict” Plan in the Performance Art Class of Junior High School－Focusing on Conflict and Bullying in schools." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/35907636267373092171.
Full textAbstract:
碩士國立臺南大學
戲劇創作與應用學系碩士班
97
The research implemented the “Cooling Conflict” action plan on the performance arts courses. The plan applied drama strategies and peer teaching to the issue of bullying and conflict in schools. Moreover the students would learn more about conflict management and reduce the ability of bullying. The purpose of the research was to explore three stages of the teaching process and the strategies applied to teaching. The research used action research on two classes of 9th graders in the junior high school. The duration was sixteen weeks and twice a week, forty-five minutes each time. The researcher analyzed the data from the observations, reflection journals, homework, feedback of students and teachers and other documents. As the research found, students gained useful knowledge in “Learning about drama”, “Learning the issue of conflict and bullying through drama” and “Learning about yourself through drama”. According to the results, the suggestions are as follows: First, the correct definition of bullying and conflict is necessary before the plan of “Cooling Conflict” and the issues of “Peer Teaching” should be chosen carefully. In order to reduce the difficulty of the play, the limitation of the script on schooling conflict is recommended. Second, using strategy of “discover the truth of fact” in scripting process could arise the conflict. Third, the elements of drama should be brought into the plays to fulfill the idea of "learning by playing" in rehearsal stage. The teacher can use questions to expand student’s life experience and integrate drama techniques into the plays in this stage. Finally, the difference between imagination and fact could be used in the “Peer Teaching” to enhance the tension of the play. Meanwhile, sufficient time for discussion is important for students after the play. In additional, the teacher couhld use drama techniques in the “Cooling Conflict” to lead students to explore the issues.
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Ozemoya, Augustine. "Controlling a photovoltaic module's surface temperature to ensure high conversion efficiency." Thesis, 2015. http://hdl.handle.net/10352/301.
Full textAbstract:
M. Tech. (Engineering, Electrical, Department Electronic Engineering, Faculty of Engineering and Technology), Vaal University of TechnologyIn order to facilitate sustainable development, it is necessary to further improve and increase the energy efficiency and use of renewable energy and its related technologies. The main limiting factors to the extensive use of photovoltaic (PV) modules include the high initial investment cost and the relatively low conversion efficiency. However, other factors, such as an increase in ambient temperature, exert a considerable negative influence on PV modules, with cell efficiencies decreasing as the cell’s operating temperature increases. Higher PV module surface temperatures mean lower output voltages and subsequent lower output power. Therefore, this dissertation focuses on optimizing the available output power from a PV module by investigating and controlling the effect that the PV module’s surface temperature exerts on the amount of electrical energy produced. A pilot study was conducted by using a PV module set to three different tilt angles with an orientation angle and temperature sensors placed at different points. This was done to determine temperature distribution on the PV module surfaces as well as identify which tilt angle produces the highest PV module surface temperature. The main study was designed to investigate the electrical performance of a PV module with different cooling systems (water and forced air) as against a referenced measurement (no cooling). The cooling systems will be switched on and off at specific time intervals with the help of an electronic timer circuit incorporating a PIC microcontroller. The pilot study was conducted for a 50 week period where the results indicated a direct correlation between temperature rise and voltage decrease. The PV module’s temperature is highest at a tilt angle of 16° during the day and lowest at night time. It further reveals that the PV module’s front and back surface temperature can be distinctly different, with the highest recorded values occurring at the back of the PV module. The main study was conducted for a period of 15 weeks with results indicating that the water cooling system resulted in an average higher output power of 49.6% when compared to the reference system (no cooling system). Recommendations are made that sufficient space should be included between the module frames and mounting structure to reduce high operating temperatures owing to poor air circulation.