Bir şalter sistemi için termal analiz

Energies, 2021

The manuscript presents advanced coupled analysis: Maxwell 3D, Transient Thermal and Fluent CFD, at the time of a rated current occurring on the main busbars in the low-voltage switchgear. The simulations were procured in order to aid the design process of such enclosures. The analysis presented the rated current flow in the switchgear busbars, which allowed determining their temperature values. The main assumption of the simulation was measurements of temperature rise during rated current conditions. Simulating such conditions is a valuable asset in order to design better solutions for energy distribution gear. The simulation model was a precise repre-sentation of the actual prototype of the switchgear. Simulations results were validated by ex-perimental research. The heat dissipation in busbars and switchgear housing through air con-vection was presented. The temperature distribution for the insulators in the rail bridge made of fireproof material was considered: halogen-free polyester. The results obtained during the sim-ulation allowed for a detailed analysis of switchgear design and proper conclusions in practical and theoretical aspects. That helped in introducing structural changes in the prepared prototype of the switchgear at the design and construction stages. Deep analysis of the simulation results allowed for the development concerning the final prototype of the switchgear, which could be subjected to the full type tests. Additionally, short-circuit current simulations were procured and presented.

International Journal of Advanced Science and Engineering, 2024

This study examines different types of heat sinks and their structures and how rectifier diode resistance affects heat production, as shown by transient and stability analyses. Overheating of electronic components, particularly switching devices and the inability of heat sinks to effectively manage thermal effects are common issues in electrical design. Properly designing heat sink environments can improve the overall design of electrical components. The transient and stability analyses show that surface temperature fluctuates, causing inconsistent heat dissipation, particularly on the plate and rib surfaces. Long radiators, in particular, exhibit significant temperature variations, with their upper sections cooling less effectively and absorbing less heat. To address these issues, a range of heat sink types were designed and analyzed using Matlab/Simulink, focusing on composition, shape, and structure. The study modeled steady-state and transient behavior, and the findings demonstrate that optimizing heat sink design and material selection can significantly improve heat dissipation, enhancing the reliability and longevity of switching devices in high-power applications.

SpringerNature, 2020

Thermal management of power electronics (PE) systems is a long-lasting challenge in their industrial applications. It is important to provide a uniform temperature distribution on the surface of the insulated gate bipolar transistors and diodes. The thermal management of a PE module is the main objective of the present study. The flow characteristics and the effects of the constructal theory on the heat transfer performance of the cooling system have been numerically investigated. The governing equations have been discretized using the finite volume method, and validation has been done to make sure the results are reliable. The effects of different channels configurations on decreasing the chips' temperature and uniform temperature distribution on the chips' surface have been studied. The flow characteristics and heat transfer performance at different mass flow rates for different channel configurations have been studied by presenting the results of the average chips' temperature, Nusselt (Nu) number, pressure loss, and standard temperature deviation. Moreover, different temperature distribution contours have been presented to show the performance of different configurations. The results revealed that by changing the channels' configuration from the conventional straight channel to leaf-inspired channels (case B and C), the cooling performance is improved. It is known that thermal management is a long-lasting challenge in electronics-related industries such as power electronics (PE) systems, battery, and wearable electronics 1-5. The applications of PE systems, which use for controlling and converting electrical energy, have been rapidly grown during the last decades. The trend of PE systems is continuing towards miniaturization and, as a result, high-performance thermal management systems are demanding, especially for insulated gate bipolar transistors (IGBTs). The most important factors affecting the technical progress and development of IGBTs are operating temperature, dimension, reliability, efficiency, and cost. With the development of IGBTs over the last thirty years, their power density has been lifted from 35 kW/cm 2 (in the early beginning) to 250 kW/cm 2 expected by 2020s. Because of high voltage, current, and miniaturization, the total heat dissipation of IGBTs follows an increasing trend. For example, the generated heat flux of IGBTs used in hybrid electric vehicles (HEV) is between 100 and 200 W/cm 2 during normal operation and is expected to reach 500 W/cm 2 in the next generation of IGBTs 6,7. Generating high heat fluxes by IGBTs results in facing higher and non-uniform temperature on IGBT chips, which results in considerable degradation of the device performance and system reliability. Thus it is highly demanding to have an effective cooling system to cool down the IGBTs. Moreover, it is known that an effective cooling solution results in enhancing the reliability of the device 8-10. One of the most important factors in thermal management of PE systems is to provide uniform temperature distribution on IGBT chips 11,12. Although increasing the heat transfer rate leads to decreasing the IGBT's temperature , it has no considerable effect on the temperature distribution of the IGBT surface. Thus having a cooling system that can cool down the IGBT chips below the maximum junction temperature (125 °C for silicon-based IGBT and 200 °C for silicon carbide-based IGBT) by providing a uniform temperature distribution on the IGBT chips surface is highly desirable in thermal management of PE systems. Researchers tried to tackle this problem by introducing the constructal theory. The constructal theory is the view that the generation of flow configuration is a physics phenomenon that can be based on physics principles 13. This theory pays attention to the geometry and arrangement of the system structure and, by optimizing the geometry and structure, maximizes the performance and efficiency of the system 14. Bejan was the first to apply structural theory in 1996 13. One of the samples of the Constructal theory is network structures, which were first used to cool electronic components 13,15,16. It can provide a more uniform temperature distribution compared to conventional MCHSs.

International Journal of Engineering Sciences & Research Technology, 2014

Thermal design and thermal analysis is necessary to effectively and efficiently cool electronic components for its best operation. This cooling method is known as electronic cooling. In the present work a finned heat sink for Electronic Unit (EU) of an Air Vehicle (AV) has been designed using the empirical heat transfer correlations by considering natural convection and radiation heat transfer modes[1] for given heat load. The preliminary calculations indicated that plane surface was inadequate to dissipate the heat, thus necessitating fins to augment the heat dissipation to the ambient. Heat transfer calculations were carried out for finned surface to find out the maximum surface temperature, which is well below the maximum permissible temperature. Further fin space optimization has been made by using empirical correlation for given heat sink to bring down the surface temperature further below.3D modelling of all the parts of the electronic unit was carried out in SolidWorks2012.Using Flo.EFD software the CFD model is generated and analysed to obtain the total thermal mapping of the above electronic unit. The CFD results were used to validate the results obtained through the excel spread sheet program developed based on the empirical correlations available in the literature.

2015 IEEE 24th International Symposium on Industrial Electronics (ISIE), 2015

Finding a global optimum of power converters requires models of all its parts (semiconductors, filters and cooling system), rules to describe the interactions between the different parts, an optimality criterion and optimization routines to converge towards the best design. In this paper we implement a model of forced-air cooling system to be used in such a design process. Heat exchange between fins and forced air is described, and fluid mechanics are used to account for the interactions between the fan and the heat sink. Using these descriptions, it is shown how a given performance index can be maximized using optimization routines. The developed model is experimentally verified in the case of a custom heat sink designed with this process. Finally, we investigate the influence of different parameters such as the fan power and characteristic, base plate, heat sink dimensions and materials.

This paper deals with the comparative study of heat sink having fins with shield of various profiles namely Trapezoidal with curved and plane inclination and slope shield as heat sinks are the commonly used devices for enhancing heat transfer in electronic components. For the purpose of study heat sink is modeled by using the optimal geometric parameter such as fin height, fin thickness, base height, fin pitch as 48 mm, 1.6 mm, 8mm, 4mm and after that simulation is done at heat load of 75W and with a air velocity of 4.7171m/s and air inlet temperature is taken as 295 K. The simulation is carried out with a commercial package provided by fluent incorporation. The result obtained taking into consideration only the thermal performance. As per the current era of the technological development everything is needed to be compact; whether it is a normal computer or laptop or the rack server we need everything that can be placed in a small space, so here the space constraint plays an major role as you cannot install a large heat sink for your device as it increases the size and the cost. So in this paper the pitch of fin is kept 4mm and heat load of 75w.

The present focus is to optimize thermal aspects for low cost effective CFD solutions of the analysis of the reasonably high-quality design. Although the method adopted for the current study is a well-known idea that is described order reduction techniques based on the transitional approach of POD and SVD to evaluate the thermal cooling aspects of circuits. The model was done on ten Watt power source IC system mounting and manufactured for an automobile application. A proper Computational Fluid Dynamics simulation was shaped to optimize the most crucial piece of the board and a valid and appropriate result has been entered. Based on the MOR techniques that are applied to the obtained results of the simulation were compared and included into the design, the modified order reduction method successfully able to approximate and standardize the cooling load and design constraints of the selected board.

Microelectronics Reliability, 2009

This paper compares four assembly solutions for power converters operating in sealed enclosures with tight temperature specifications. The specific application of interest is one of the DC/DC converters of a power supply system to be used in high-energy-physics experiments: the sealed case must not significantly alter the temperature of the surrounding components (detectors and their electronics). The comparison is made using 3D Finite Element thermal modeling. The standard FR4 board solution is shown not to be viable under these tight temperature specs; we therefore explore alternative assemblies for the stack connecting the active devices to the heat-sink.

2000

The objective of the present study is to perform thermal analysis for the design of a complex electronic cabinet used as a high speed Internet subscriber device. The novelty of the paper lies in the approach used for analysis of the flow distribution in the system of interest. It utilizes Flow Network Modeling (FNM) and Computational Fluid Dynamics (CFD) in complementary and interactive manner for quick and accurate thermal analysis of the entire system. The enclosure consists of thirteen PCB's and two axial fans. In the analysis of the flow distribution, the flow through the passages formed by adjacent PCBs along with the inlet region is analyzed using the CFD technique to generate flow impedance characteristics. A flow network model of the entire system is then constructed by interconnecting the various components of the system in a manner that represents the paths followed by the air as it moves through the system. The CFD-based impedance characteristics in combination with the loss characteristics available from handbooks are ascribed to individual components in the network model. The FNM-based analysis of the entire system accounts for the interaction of the fan curve and the flow impedances to predict the flow distribution of air throughout the system. These results are, in turn, used to provide boundary conditions in the CFD analysis for the prediction of detailed flow distribution in individual card passages in order to obtain a thermal map of the PCBs. The predicted flow rates through the individual card passages are within 10% of the experimentally measured values. The analysis approach couples the power of CFD with the speed and flexibility of the FNM technique to enable accurate prediction of the flow distribution throughout the system in the most efficient manner. Further, the modularity of the proposed approach allows quick and scientific examination of the design changes such as use of different filters, screens, or fans and easy identification of performance-limiting components. The complementary use of CFD and FNM reduces the time required for thermal analysis by an order of magnitude over the approach that uses only the CFD technique

2007

This is to certify that thesis entitled, "CFD ANALYSIS OF ELECTRONICS CHIP COOLING" submitted by Mr. SAROJ KUMAR PATRA in partial fulfillment of the requirements for the award of Master of Technology Degree in Mechanical Engineering with specialization in "Thermal Engineering" at National Institute of Technology, Rourkela (Deemed University) is an authentic work carried out by him under my supervision and guidance. To the best of my knowledge, the matter embodied in this thesis has not been submitted to any other university/ institute for award of any Degree or Diploma.