首页期刊导航|Thermal science and engineering progress
期刊信息/Journal information
Thermal science and engineering progress
Elsevier Ltd.
Thermal science and engineering progress

Elsevier Ltd.

2451-9049

Thermal science and engineering progress/Journal Thermal science and engineering progressSCI
正式出版
收录年代

    A technology overview of thermal management of integrated motor drives-Electrical Machines

    Wrobel, Rafal
    14页
    查看更多>>摘要：This paper provides a technology overview of integrated motor drives (IMDs), with a focus on thermal management of high-specific-output and high-efficiency electrical machines. The early examples of integrating electronics with electrical machines were introduced in the 1960's. Here, both passive and active cooling techniques were employed to provide compact and robust electronics-motor systems, predominantly for automotive and aerospace applications. The latest examples of IMDs share the same generic concepts of thermal management, where dedicated or shared cooling of the individual IMD subsystems is used. However, the modern IMDs illustrate a more comprehensive integration approach, where the complete power electronics inverter and electrical machine are frequently accompanied by other subsystems, e.g. mechanical transmission, suspension, clutching, braking and others. Again, the automotive and aerospace industries have been paving the way towards high-specific-output and high-efficiency IMDs, but it is important to note that the low-power applications, e.g. consumers electronics, health and beauty goods, home appliances, garden and power tools, personal mobility vehicles and many others have been adopting the IMDs for decades now. Interestingly, some of the generic concepts first successfully introduced in low-power devices found their use in more demanding high-power applications.In general, thermal management of electrical machines in IMDs is analogous to that used in discrete motor drives (DMDs). The continuous drive towards high-specific-output and high-efficiency electrical machines have been imposing ever more demanding challenges associated with effective heat removal from the machine composite structure, with multiple localised and non-homogenous heat sources. It is important to note that balancing both generated power losses (heat), and available heat removal is essential for successful implementation of a specific machine design. The existing examples of advanced motor cooling offer a more targeted approach for removing heat directly or indirectly from the individual heat sources, e.g. direct winding oil spray cooling, forced air rotor cooling, and indirect stator-winding heat exchanger cooling, stator-winding heat guide transport. Some of the concepts originate from high-power and high-efficiency electrical machines for power generation, others are enabled by the developments in new materials and manufacturing techniques. It is evident that a more focused thermal management aiming at specific heat sources is the most effective. Here, the use of additive manufacturing, highly integrated heat exchangers, multi-functional composite materials and phase change heat transport and heat storage are some of the solutions, which have already shown a great promise for the next generation of IMDs.
      原文链接:
    • NSTL
    • Elsevier

    Heat pipe-based waste heat recovery systems: Background and applications

    Olabi, A. G.Abdelkareem, Mohammad AliMaghrabie, Hussein M.Sayed, Enas Taha...
    26页
    查看更多>>摘要：Heat pipes are becoming gradually more popular as a passive heat transfer technology due to their effective performance. The heat pipe heat exchanger (HPHE) is an effective tool in recovering waste heat. The present paper provides a comprehensive review of the state-of-the-art background of heat pipe for various waste heat recovery systems (WHRSs). Furthermore, the present paper focuses on a number of the most prevalent applications of utilizing heat pipe for WHR such as heating ventilating and air conditioning (HVAC) systems, solar photovoltaic, water desalination, ceramic kiln industry, steel industry, internal combustion engines, generators, and electronic components in which the heat pipe introduces several benefits. The waste heat resource, type and description of the employed heat pipe, and the working fluid for each application are studied comprehensively. Internal and external thermal modeling techniques, theories, and methodologies are presented for various applications. Based on the energy efficiency improvement, economic investment, and environmental impacts, the employing of HPHE in different applications is a successful and promising technology. Finally, the current challenges and future perspectives related to the use of the heat pipe for WHR in various applications are introduced.
      原文链接:
    • NSTL
    • Elsevier

    Effect of beta angle and contact conductances on the temperature distribution of a 3U CubeSat

    Garzon, AlejandroTami, John A.Campos-Julca, Cristhiam D.Acero-Nino, Ignacio F....
    16页
    查看更多>>摘要：Contact conductances are a significant factor in the thermal analysis aimed at assuring safe on-orbit temperatures for a nanosatellite. In this work, the effect of the thermal contact conductances and the beta angle on the temperature of the components of a realistic 3U CubeSat model is investigated theoretically. As part of the explanation of the methodology used, Python scripts are provided that compute the temperature of a simplified multinodal model. When beta = 0 degrees, the subsystems of the realistic satellite model present temperatures within their operating ranges for contact conductance variations spanning an order of magnitude. Reduction of the contact conductances yields dissimilar effects on the internal and external components: the amplitudes and average values of the temperature oscillation of external components, like the solar cells, increase; in contrast, the oscillation amplitudes of internal components decrease and insignificant changes are observed in their average temperature. Increase of beta from 0 degrees to 75 degrees produces a raise of the average temperature, but a decrement of the oscillation amplitude, for all subsystems. All components stay inside their operating ranges, for beta from 0 degrees to 15 degrees. The results suggest that, if the payload (camera) is insulated, this domain could be extended up to beta = 45 degrees. We expect that our results will guide the design of CubeSat missions.
      原文链接:
    • NSTL
    • Elsevier

    A critical review of parameters governing the boiling characteristics of tube bundle on shell side of two-phase shell and tube heat exchangers

    Moharana, SubhakantaBhattacharya, AnirbanDas, Mihir Kumar
    28页
    查看更多>>摘要：Heat transfer by the process of boiling is advantageous due to the high heat transfer coefficient associated with the process. In many heat transfer applications, boiling on tubes and tube bundles are encountered. Tube bundle studies are important as these are an integral part of shell and tube heat exchangers, reboilers, evaporators used commercially both in industrial and non-industrial applications. Similarly, tube bundles with vertical configuration are integral part of nuclear reactors. In this review, the effects of different parameters affecting heat transfer in tube bundles on the shell side of two-phase shell and tube heat exchangers are analysed based on available literature. The studies included are subdivided into effect of performance parameters for flow boiling and for pool boiling. The pool boiling heat transfer devices do not require any active flow equipment, whereas in case of flow boiling active flow equipment is essential for continuously supplying the working fluid. In order to design an effective heat exchanging device having tube bundles the combined effect of parameters such as heat flux, mass flux, quality, tube geometry, spacing etc. need to be considered. This article highlights various critical parameters, considered by studies available in the open literature, which affect the heat transfer in two-phase flow heat exchanging devices.
      原文链接:
    • NSTL
    • Elsevier

    Study of hydrothermal transport phenomena and performance characteristics for a flow through a diamond (diverging-converging) microchannel

    Agrawal, AmitGoli, SandeepSaha, Sandip K.
    19页
    查看更多>>摘要：A three-dimensional computational module is undertaken to assimilate the hydrothermal transport phenomena and performance characteristics of a single-phase laminar flow through a diamond (diverging-converging) microchannel. The fluid flow and heat transfer characteristics are investigated as a function of divergenceconvergence angle, width ratio (ratio of bigger width to smaller width), and Reynolds number. The results are explained with the help of velocity and temperature profiles. The present study also utilizes thermal enhancement factor, pressure penalty factor, performance evaluation index, frictional and thermal entropy generation, Bejan number, and augmented entropy generation number to analyze the hydrothermal and thermodynamic performance characteristics of a diamond microchannel. The Nusselt number is found to be a direct function of the divergence-convergence angle, while it varies inversely with the width ratio. The varying divergenceconvergence angle effectively constrains the rise in the overall temperature gradient, while the width ratio has a weak but opposite effect on the temperature gradients. The results also indicate that the diamond microchannel exhibits better hydrothermal and thermodynamic performance than the uniform microchannel. For a given range of parameters, the maximum value of the performance evaluation index is 1.42, and the maximum reduction in entropy generation is 28% relative to a uniform microchannel. These results would serve as a valuable guide for designing and optimizing microchannels with diverging-converging profiles required in several heat transfer applications.
      原文链接:
    • NSTL
    • Elsevier

    Modification of the DRTA probes geometry for an environment with a high proportion of the radiant heat flux

    Schmirler, MichalSlama, Pavel
    7页
    查看更多>>摘要：The Recovery Temperature Anemometry (RTA) is a method for determining the flow field velocity of a compressible fluid by measuring temperatures, in which the temperature rendered by temperature probes positioned within an airflow is determined by the thermodynamic temperature, the external flow velocity, the fluid's specific heat, and the probe's recovery factor. There is one drawback to employing a single temperature probe in the RTA approach. Even if the probe's recovery factor and isobaric heat capacity are known, the external flow velocity for the evaluation of the thermodynamic temperature or the thermodynamic temperature for the evaluation of the flow velocity must be known as well. The Double Probe Recovery Temperature Anemometry (DRTA) method, which uses two or more temperature probes with different recovery factors, has overcome this problem. The geometry of a previously proposed DRTA probe, which was originally sensitive to ambient heat radiation, was improved in this research. The qualities were improved by using a shield for both temperature sensors while maintaining their separate recovery factors. The alteration of the geometry of the original probe and experimental verification of its parameters are described in this paper.
      原文链接:
    • NSTL
    • Elsevier

    Effect of wall heat transfer on the dynamics of premixed spherical expanding flames

    Mouze-Mornettas, A.Keck, H.Wang, Y.Chen, Z....
    9页
    查看更多>>摘要：Premixed laminar flame speed determination is a crucial point since its values are used for the sizing of every combustion systems. In order to measure this parameter, an isochoric combustion method can be used. It consists in measuring the pressure (and possibly other parameters) for a spherical expanding flame. This method allows to get flame speed data for a large scope of important pressures and temperatures supposing an isentropic compression. However, the entirety of the flame propagation process cannot be used to compute the flame speed as heat losses will start to appear as the flame come close the wall, making the isentropic compression assumption invalid. In order to precisely determine when significative heat losses occur, a criterion based on the evolution of the flame preheat zone thickness is described in this paper. The evaluation of this new method is performed using Direct Numerical Simulations for different mixtures (methane with various diluents) at different equivalence ratios and thermodynamic conditions. Finally, the criterion is compared to already existing methods, showing a relatively good accuracy to describe wall heat losses effect on the flame dynamics at high pressure.
      原文链接:
    • NSTL
    • Elsevier

    Optimal interstage pressures of multistage compression with intercooling processes

    Jarungthammachote, Sompop
    13页
    查看更多>>摘要：This study develops a method to determine the optimal interstage pressures for two-stage and three-stage compressions with intercoolers. The developed method can also be applied using multi-loop calculation for compression involving more than three stages. The developed relationship is expressed in terms of temperatures, densities and the derivative of entropy with respect to pressure. The properties used in this study are calculated from the multiparameter equations of state. Equations of optimal interstage pressures for the nonequal inlet temperature of compressors based on the ideal gas assumption, called an ideal gas model, are found and investigated. The study results show that for the high pressure and low temperature region, the ideal gas model cannot predict the interstage pressure that minimizes the total specific compression work. High pressure and low temperature are considered by comparing the critical pressure and temperature of the considered gas. The developed model can provide the optimal interstage pressure which causes minimum total compression work even if the compressions are conducted in a high pressure and low temperature region. For two-stage compression of CO2 from 6.25 MPa, 305 K to 20 MPa with isentropic efficiencies of 0.9, the developed method can save 16.63% of specific compression work, comparing to the ideal gas model. For the developed method, if the isentropic efficiency of the stage compressor increases, the calculated optimal interstage pressure raised by that stage also increases. The increase in outlet temperature of the intercooler causes increasing optimal value of interstage pressure raised by the previous compression stage.
      原文链接:
    • NSTL
    • Elsevier