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Thermal and Electro-thermal System Simulation 2020

A special issue of Energies (ISSN 1996-1073). This special issue belongs to the section "J: Thermal Management".

Deadline for manuscript submissions: closed (15 July 2020) | Viewed by 56997

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Guest Editor
Department of Electron Devices, Budapest University of Technology and Economics, H-1117 Budapest, Hungary
Interests: thermal investigation of ICs and MEMS; thermal sensors; thermal testing; thermal simulation; thermal model generation; electro-thermal simulation; CPS systems
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Guest Editor
Department of Electronics, Information and Bioengineering, Politecnico di Milano, 20133 Milan, Italy
Interests: electric engineering; electro-thermal circuit modeling and simulation; electromagnetic simulation
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Guest Editor
Department of Electron Devices, Budapest University of Technology and Economics; Magyar tudósok körútja 2, bldg. Q, 1117 Budapest, Hungary
Interests: LED testing; thermal simulation; electro-thermal simulation; logi-thermal simulation; multi-domain modeling
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

As a follow-up to the 25th THERMINIC Workshop, held in Lecco in September 2019, a Special Issue of energies about thermal and multi-physical investigations electronics systems will be edited by Prof. Marta Rencz, Prof. Lorenzo Codecasa and Prof. Andras Poppe.

This Special Issue will target the presentation of the newest research results of thermal effects in electronics today, from characterization to through multi-physics simulation to cooling solutions and reliability assessment.

This special issue is not only collecting papers from the 25th THERMINIC Workshop, but also will containing papers from other scholars who interested in this topic. Papers that were presented at THERMINIC must be revised and contain at least 60% new material that has never been presented before.

Prof. Márta Rencz
Prof. Lorenzo Codecasa
Prof. Andras Poppe
Guest Editors

Manuscript Submission Information

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Keywords

  • multi physics simulation and field coupling
  • thermal modelling and investigation of packages
  • thermal interface materials and their characterization
  • thermal management and characterization of electronic components and systems
  • high temperature electronics
  • thermal issues in power electronics
  • thermal issues in solid state lighting
  • CFD modelling and benchmarking
  • thermal performance of interconnects
  • electro-thermal interactions
  • temperature mapping
  • 3D integration and cooling concepts
  • thermo-mechanical reliability
  • lifetime modelling and prediction
  • prognostics and health monitoring

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Published Papers (14 papers)

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19 pages, 9090 KiB  
Article
Digital Luminaire Design Using LED Digital Twins—Accuracy and Reduced Computation Time: A Delphi4LED Methodology
by Marc van der Schans, Joan Yu and Genevieve Martin
Energies 2020, 13(18), 4979; https://doi.org/10.3390/en13184979 - 22 Sep 2020
Cited by 12 | Viewed by 2894
Abstract
Light-emitting diode (LED) digital twins enable the implementation of fast digital design flows for LED-based products as the lighting industry moves towards Industry 4.0. The LED digital twin developed in the European project Delphi4LED mimics the thermal-electrical-optical behavior of a physical LED. It [...] Read more.
Light-emitting diode (LED) digital twins enable the implementation of fast digital design flows for LED-based products as the lighting industry moves towards Industry 4.0. The LED digital twin developed in the European project Delphi4LED mimics the thermal-electrical-optical behavior of a physical LED. It consists of two parts: a package-level LED compact thermal model (CTM), coupled to a chip-level multi-domain model. In this paper, the accuracy and computation time reductions achieved by using LED CTMs, compared to LED detailed thermal models, in 3D system-level models with a large number of LEDs are investigated. This is done up to luminaire-level, where all heat transfer mechanisms are accounted for, and up to 60 LEDs. First, we characterize a physical phosphor-converted white high-power LED and apply LED-level modelling to produce an LED detailed model and an LED CTM following the Delphi4LED methodology. It is shown that the steady-state junction temperature errors of the LED CTM, compared to the detailed model, are smaller than 2% on LED-level. To assess the accuracy and the reduction of computation time that can be realized in a 3D system-level model with a large number of LEDs, two use cases are considered: (1) an LED module-level model, and (2) an LED luminaire-level model. In the LED module-level model, the LED CTMs predict junction temperatures within about 6% of the LED detailed models, and reduce the calculation time by up to nearly a factor 13. In the LED luminaire-level model, the LED CTMs predict junctions temperatures within about 1% of LED detailed models and reduce the calculation time by about a factor of 4. This shows that the achievable computation time reduction depends on the complexity of the 3D model environment. Nevertheless, the results demonstrate that using LED CTMs has the potential to significantly decrease computation times in 3D system-level models with large numbers of LEDs, while maintaining junction temperature accuracy. Full article
(This article belongs to the Special Issue Thermal and Electro-thermal System Simulation 2020)
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22 pages, 4983 KiB  
Article
Investigation and Modeling of the Magnetic Nanoparticle Aggregation with a Two-Phase CFD Model
by Péter Pálovics, Márton Németh and Márta Rencz
Energies 2020, 13(18), 4871; https://doi.org/10.3390/en13184871 - 17 Sep 2020
Cited by 11 | Viewed by 2869
Abstract
In this paper the magnetic nanoparticle aggregation procedure in a microchannel in the presence of external magnetic field is investigated. The main goal of the work was to establish a numerical model, capable of predicting the shape of the nanoparticle aggregate in a [...] Read more.
In this paper the magnetic nanoparticle aggregation procedure in a microchannel in the presence of external magnetic field is investigated. The main goal of the work was to establish a numerical model, capable of predicting the shape of the nanoparticle aggregate in a magnetic field without extreme computational demands. To that end, a specialized two-phase CFD model and solver has been created with the open source CFD software OpenFOAM. The model relies on the supposed microstucture of the aggregate consisting of particle chains parallel to the magnetic field. First, the microstructure was investigated with a micro-domain model. Based on the theoretical model of the particle chain and the results of the micro-domain model, a two-phase CFD model and solver were created. After this, the nanoparticle aggregation in a microchannel in the field of a magnet was modeled with the solver at different flow rates. Measurements with a microfluidic device were performed to verify the simulation results. The impact of the aggregate on the channel heat transfer was also investigated. Full article
(This article belongs to the Special Issue Thermal and Electro-thermal System Simulation 2020)
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39 pages, 14646 KiB  
Article
Mixed Detailed and Compact Multi-Domain Modeling to Describe CoB LEDs
by László Pohl, Gusztáv Hantos, János Hegedüs, Márton Németh, Zsolt Kohári and András Poppe
Energies 2020, 13(16), 4051; https://doi.org/10.3390/en13164051 - 5 Aug 2020
Cited by 9 | Viewed by 3240
Abstract
Large area multi-chip LED devices, such as chip-on-board (CoB) LEDs, require the combined use of chip-level multi-domain compact LED models (Spice-like compact models) and the proper description of distributed nature of the thermal environment (the CoB substrate and phosphor) of the LED chips. [...] Read more.
Large area multi-chip LED devices, such as chip-on-board (CoB) LEDs, require the combined use of chip-level multi-domain compact LED models (Spice-like compact models) and the proper description of distributed nature of the thermal environment (the CoB substrate and phosphor) of the LED chips. In this paper, we describe such a new numerical solver that was specifically developed for this purpose. For chip-level, the multi-domain compact modeling approach of the Delphi4LED project is used. This chip-level model is coupled to a finite difference scheme based numerical solver that is used to simulate the thermal phenomena in the substrate and in the phosphor (heat transfer and heat generation). Besides solving the 3D heat-conduction problem, this new numerical simulator also tracks the propagation and absorption of the blue light emitted by the LED chips, as well as the propagation and absorption of the longer wavelength light that is converted by the phosphor from blue. Heat generation in the phosphor, due to conversion loss (Stokes shift), is also modeled. To validate our proposed multi-domain model of the phosphor, dedicated phosphor and LED package samples with known resin—phosphor powder ratios and known geometry were created. These samples were partly used to identify the nature of the temperature dependence of phosphor-conversion efficiency and were also used as simple test cases to “calibrate” and test the new numerical solver. With the models developed, combined simulation of the LED chip and the CoB substrate + phosphor for a known CoB LED device is shown, and the simulation results are compared to measurement results. Full article
(This article belongs to the Special Issue Thermal and Electro-thermal System Simulation 2020)
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13 pages, 3732 KiB  
Article
Influence of a Thermal Pad on Selected Parameters of Power LEDs
by Krzysztof Górecki, Przemysław Ptak, Tomasz Torzewicz and Marcin Janicki
Energies 2020, 13(14), 3732; https://doi.org/10.3390/en13143732 - 20 Jul 2020
Cited by 9 | Viewed by 2877
Abstract
This paper is devoted to the analysis of the influence of thermal pads on electric, optical, and thermal parameters of power LEDs. Measurements of parameters, such as thermal resistance, optical efficiency, and optical power, were performed for selected types of power LEDs operating [...] Read more.
This paper is devoted to the analysis of the influence of thermal pads on electric, optical, and thermal parameters of power LEDs. Measurements of parameters, such as thermal resistance, optical efficiency, and optical power, were performed for selected types of power LEDs operating with a thermal pad and without it at different values of the diode forward current and temperature of the cold plate. First, the measurement set-up used in the paper is described in detail. Then, the measurement results obtained for both considered manners of power LED assembly are compared. Some characteristics that illustrate the influence of forward current and temperature of the cold plate on electric, thermal, and optical properties of the tested devices are presented and discussed. It is shown that the use of the thermal pad makes it possible to achieve more advantageous values of operating parameters of the considered semiconductor devices at lower values of their junction temperature, which guarantees an increase in their lifetime. Full article
(This article belongs to the Special Issue Thermal and Electro-thermal System Simulation 2020)
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15 pages, 1280 KiB  
Article
Electro-Thermal Simulation of Vertical VO2 Thermal-Electronic Circuit Elements
by Mahmoud Darwish, Péter Neumann, János Mizsei and László Pohl
Energies 2020, 13(13), 3447; https://doi.org/10.3390/en13133447 - 3 Jul 2020
Cited by 6 | Viewed by 3725
Abstract
Advancement of classical silicon-based circuit technology is approaching maturity and saturation. The worldwide research is now focusing wide range of potential technologies for the “More than Moore” era. One of these technologies is thermal-electronic logic circuits based on the semiconductor-to-metal phase transition of [...] Read more.
Advancement of classical silicon-based circuit technology is approaching maturity and saturation. The worldwide research is now focusing wide range of potential technologies for the “More than Moore” era. One of these technologies is thermal-electronic logic circuits based on the semiconductor-to-metal phase transition of vanadium dioxide, a possible future logic circuits to replace the conventional circuits. In thermal-electronic circuits, information flows in a combination of thermal and electronic signals. Design of these circuits will be possible once appropriate device models become available. Characteristics of vanadium dioxide are under research by preparing structures in laboratory and their validation by simulation models. Modeling and simulation of these devices is challenging due to several nonlinearities, discussed in this article. Introduction of custom finite volumes method simulator has however improved handling of special properties of vanadium dioxide. This paper presents modeling and electro-thermal simulation of vertically structured devices of different dimensions, 10 nm to 300 nm layer thicknesses and 200 nm to 30 μm radii. Results of this research will facilitate determination of sample sizes in the next phase of device modeling. Full article
(This article belongs to the Special Issue Thermal and Electro-thermal System Simulation 2020)
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30 pages, 6315 KiB  
Article
Lifetime Modelling Issues of Power Light Emitting Diodes
by János Hegedüs, Gusztáv Hantos and András Poppe
Energies 2020, 13(13), 3370; https://doi.org/10.3390/en13133370 - 1 Jul 2020
Cited by 20 | Viewed by 4315
Abstract
The advantages of light emitting diodes (LEDs) over previous light sources and their continuous spread in lighting applications is now indisputable. Still, proper modelling of their lifespan offers additional design possibilities, enhanced reliability, and additional energy-saving opportunities. Accurate and rapid multi-physics system level [...] Read more.
The advantages of light emitting diodes (LEDs) over previous light sources and their continuous spread in lighting applications is now indisputable. Still, proper modelling of their lifespan offers additional design possibilities, enhanced reliability, and additional energy-saving opportunities. Accurate and rapid multi-physics system level simulations could be performed in Spice compatible environments, revealing the optical, electrical and even the thermal operating parameters, provided, that the compact thermal model of the prevailing luminaire and the appropriate elapsed lifetime dependent multi-domain models of the applied LEDs are available. The work described in this article takes steps in this direction in by extending an existing multi-domain LED model in order to simulate the major effect of the elapsed operating time of LEDs used. Our approach is based on the LM-80-08 testing method, supplemented by additional specific thermal measurements. A detailed description of the TM-21-11 type extrapolation method is provided in this paper along with an extensive overview of the possible aging models that could be used for practice-oriented LED lifetime estimations. Full article
(This article belongs to the Special Issue Thermal and Electro-thermal System Simulation 2020)
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23 pages, 670 KiB  
Article
A Novel Method for Thermal Modelling of Photovoltaic Modules/Cells under Varying Environmental Conditions
by Ali Kareem Abdulrazzaq, Balázs Plesz and György Bognár
Energies 2020, 13(13), 3318; https://doi.org/10.3390/en13133318 - 29 Jun 2020
Cited by 12 | Viewed by 2813
Abstract
Temperature has a significant effect on the photovoltaic module output power and mechanical properties. Measuring the temperature for such a stacked layers structure is impractical to be carried out, especially when we talk about a high number of modules in power plants. This [...] Read more.
Temperature has a significant effect on the photovoltaic module output power and mechanical properties. Measuring the temperature for such a stacked layers structure is impractical to be carried out, especially when we talk about a high number of modules in power plants. This paper introduces a novel thermal model to estimate the temperature of the embedded electronic junction in modules/cells as well as their front and back surface temperatures. The novelty of this paper can be realized through different aspects. First, the model includes a novel coefficient, which we define as the forced convection adjustment coefficient to imitate the module tilt angle effect on the forced convection heat transfer mechanism. Second, the new combination of effective sub-models found in literature producing a unique and reliable method for estimating the temperature of the PV modules/cells by incorporating the new coefficient. In addition, the paper presents a comprehensive review of the existing PV thermal sub-models and the determination expressions of the related parameters, which all have been tested to find the best combination. The heat balance equation has been employed to construct the thermal model. The validation phase shows that the estimation of the module temperature has significantly improved by introducing the novel forced convection adjustment coefficient. Measurements of polycrystalline and amorphous modules have been used to verify the proposed model. Multiple error indication parameters have been used to validate the model and verify it by comparing the obtained results to those reported in recent and most accurate literature. Full article
(This article belongs to the Special Issue Thermal and Electro-thermal System Simulation 2020)
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17 pages, 7616 KiB  
Article
Thermo-Fluidic Characterizations of Multi-Port Compact Thermal Model of Ball-Grid-Array Electronic Package
by Valentin Bissuel, Frédéric Joly, Eric Monier-Vinard, Alain Neveu and Olivier Daniel
Energies 2020, 13(11), 2968; https://doi.org/10.3390/en13112968 - 9 Jun 2020
Cited by 2 | Viewed by 2515
Abstract
The concept of a single-input/multi-output thermal network was proposed by the Development of Libraries of Physical models for an Integrated design environment (DELPHI) consortium more than twenty years ago. The present work highlights the recent improvements made to efficiently derive a low-computing-effort model [...] Read more.
The concept of a single-input/multi-output thermal network was proposed by the Development of Libraries of Physical models for an Integrated design environment (DELPHI) consortium more than twenty years ago. The present work highlights the recent improvements made to efficiently derive a low-computing-effort model from a fully detailed numerical model and to characterize its performances. The temperature predictions of a deduced ball-grid-array (BGA) dynamic compact thermal model are compared to those of a realistic three-dimensional representation, including the large set of internal copper traces, as well as its board structure, which has been validated by experiment. The current study discloses a method for creating an amalgam reduced-order modal model (AROMM) for that electronic component family that allows the preservation of the geometry integrity and shortening scenarios computation. Typically, the AROMM method reduces by a factor of 600 the computation time needed to obtain the solution while keeping the error on the maximum temperature below 2%. Then, a meta-heuristic optimization is run to derive a more practical low-order resistor capacitor model that enables a thermo-fluidic analysis at the board level. Based on the calibrated numerical model, a novel AROMM method was investigated in order to address the chip behavior submitted to multiple heat sources. The first results highlight the capability to enforce a non-uniform power distribution on the upper surface of the silicon chip. Thus, the chip design layout can be analyzed and optimized to prevent thermal and reliability issues. Full article
(This article belongs to the Special Issue Thermal and Electro-thermal System Simulation 2020)
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17 pages, 8031 KiB  
Article
Compact Thermal Model of the Pulse Transformer Taking into Account Nonlinearity of Heat Transfer
by Krzysztof Górecki, Kalina Detka and Krzysztof Górski
Energies 2020, 13(11), 2766; https://doi.org/10.3390/en13112766 - 1 Jun 2020
Cited by 27 | Viewed by 2581
Abstract
This paper presents a compact nonlinear thermal model of pulse transformers. The proposed model takes into account differentiation in values of the temperatures of a ferromagnetic core and each winding. The model is formulated in the form of an electric network realising electrothermal [...] Read more.
This paper presents a compact nonlinear thermal model of pulse transformers. The proposed model takes into account differentiation in values of the temperatures of a ferromagnetic core and each winding. The model is formulated in the form of an electric network realising electrothermal analogy. It consists of current sources representing power dissipated in the core and in each of the windings, capacitors representing thermal capacitances and controlled current sources modelling the influence of dissipated power on the thermal resistances in the proposed model. Both self-heating phenomena in each component of the transformer and mutual thermal couplings between each pair of these components are taken into account. A description of the elaborated model is presented, and the process to estimate the model parameters is proposed. The proposed model was verified experimentally for different transformers. Good agreement between the calculated and measured waveforms of each component temperature of the tested pulse transformers was obtained. Differences between the results of measurements and calculations did not exceed 9% for transformers with a toroidal core and 13% for planar transformers. Full article
(This article belongs to the Special Issue Thermal and Electro-thermal System Simulation 2020)
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17 pages, 3209 KiB  
Article
Thermal Characterization and Modelling of AlGaN-GaN Multilayer Structures for HEMT Applications
by Lisa Mitterhuber, René Hammer, Thomas Dengg and Jürgen Spitaler
Energies 2020, 13(9), 2363; https://doi.org/10.3390/en13092363 - 9 May 2020
Cited by 29 | Viewed by 5365
Abstract
To optimize the thermal design of AlGaN-GaN high-electron-mobility transistors (HEMTs), which incorporate high power densities, an accurate prediction of the underlying thermal transport mechanisms is crucial. Here, a HEMT-structure (Al0.17Ga0.83N, GaN, Al0.32Ga0.68N and AlN on [...] Read more.
To optimize the thermal design of AlGaN-GaN high-electron-mobility transistors (HEMTs), which incorporate high power densities, an accurate prediction of the underlying thermal transport mechanisms is crucial. Here, a HEMT-structure (Al0.17Ga0.83N, GaN, Al0.32Ga0.68N and AlN on a Si substrate) was investigated using a time-domain thermoreflectance (TDTR) setup. The different scattering contributions were investigated in the framework of phonon transport models (Callaway, Holland and Born-von-Karman). The thermal conductivities of all layers were found to decrease with a temperature between 300 K and 773 K, due to Umklapp scattering. The measurement showed that the AlN and GaN thermal conductivities were a magnitude higher than the thermal conductivity of Al0.32Ga0.68N and Al0.17Ga0.83N due to defect scattering. The layer thicknesses of the HEMT structure are in the length scale of the phonon mean free path, causing a reduction of their intrinsic thermal conductivity. The size-effect of the cross-plane thermal conductivity was investigated, which showed that the phonon transport model is a critical factor. At 300 K, we obtained a thermal conductivity of (130 ± 38) Wm−1K−1 for the (167 ± 7) nm thick AlN, (220 ± 38) Wm−1K−1 for the (1065 ± 7) nm thick GaN, (11.2 ± 0.7) Wm−1K−1 for the (423 ± 5) nm thick Al0.32Ga0.68N, and (9.7 ± 0.6) Wm−1K−1 for the (65 ± 5) nm thick Al0.17Ga0.83N. Respectively, these conductivity values were found to be 24%, 90%, 28% and 16% of the bulk values, using the Born-von-Karman model together with the Hua–Minnich suppression function approach. The thermal interface conductance as extracted from the TDTR measurements was compared to results given by the diffuse mismatch model and the phonon radiation limit, suggesting contributions from inelastic phonon-scattering processes at the interface. The knowledge of the individual thermal transport mechanisms is essential for understanding the thermal characteristics of the HEMT, and it is useful for improving the thermal management of HEMTs and their reliability. Full article
(This article belongs to the Special Issue Thermal and Electro-thermal System Simulation 2020)
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16 pages, 4449 KiB  
Article
TRIC: A Thermal Resistance and Impedance Calculator for Electronic Packages
by Lorenzo Codecasa, Francesca De Viti, Vincenzo d’Alessandro, Donata Gualandris, Arianna Morelli and Claudio Maria Villa
Energies 2020, 13(9), 2252; https://doi.org/10.3390/en13092252 - 4 May 2020
Cited by 5 | Viewed by 2715
Abstract
This paper presents the Thermal Resistance and Impedance Calculator (TRIC) tool devised for the automatic extraction of thermal metrics of package families of electronic components in both static and transient conditions. TRIC relies on a solution algorithm based on a novel projection-based approach, [...] Read more.
This paper presents the Thermal Resistance and Impedance Calculator (TRIC) tool devised for the automatic extraction of thermal metrics of package families of electronic components in both static and transient conditions. TRIC relies on a solution algorithm based on a novel projection-based approach, which—unlike previous techniques—allows (i) dealing with parametric detailed thermal models (pDTMs) of package families that exhibit generic non-Manhattan variations of geometries and meshes, and (ii) transforming such pDTMs into compact thermal models that can be solved in short times. Thermal models of several package families are available, and dies with multiple active areas can be handled. It is shown that transient thermal responses of chosen packages can be obtained in a CPU (central processing unit) time much shorter than that required by a widely used software relying on the finite-volume method without sacrificing accuracy. Full article
(This article belongs to the Special Issue Thermal and Electro-thermal System Simulation 2020)
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18 pages, 7636 KiB  
Article
Compact Thermal Modelling Tool for Fast Design Space Exploration of 3D ICs with Integrated Microchannels
by Piotr Zając
Energies 2020, 13(9), 2217; https://doi.org/10.3390/en13092217 - 2 May 2020
Cited by 5 | Viewed by 2636
Abstract
Integrated microchannel cooling is a very promising concept for thermal management of 3D ICs, because it offers much higher cooling performance than conventional forced-air convection. The thermo-fluidic simulations of such chips are usually performed using a computational fluid dynamics (CFD) approach. However, due [...] Read more.
Integrated microchannel cooling is a very promising concept for thermal management of 3D ICs, because it offers much higher cooling performance than conventional forced-air convection. The thermo-fluidic simulations of such chips are usually performed using a computational fluid dynamics (CFD) approach. However, due to the complexity of the fluid flow modelling, such simulations are typically very long and faster models are therefore considered. This paper demonstrates the advantages of TIMiTIC—a compact thermal simulator for chips with liquid cooling—and shows its practical usefulness in design space exploration of 3D ICs with integrated microchannels. Moreover, thermal simulations of a 3D processor model using the proposed tool are used to estimate the optimal power dissipation profile in the chip and to prove that such an optimal profile allows for a very significant (more than 10 °C) peak temperature reduction. Finally, a custom correlation metric is introduced which allows the comparison of the power distribution profiles in terms of the peak chip temperature that they produce. Statistical analysis of the simulation results demonstrates that this metric is very accurate and can be used for example in thermal-aware task scheduling or dynamic voltage and frequency scaling (DVFS) algorithms. Full article
(This article belongs to the Special Issue Thermal and Electro-thermal System Simulation 2020)
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29 pages, 7148 KiB  
Article
On the Reproducibility of Thermal Measurements and of Related Thermal Metrics in Static and Transient Tests of Power Devices
by Gabor Farkas, Dirk Schweitzer, Zoltan Sarkany and Marta Rencz
Energies 2020, 13(3), 557; https://doi.org/10.3390/en13030557 - 23 Jan 2020
Cited by 10 | Viewed by 3874
Abstract
Traditionally the thermal behavior of power devices is characterized by temperature measurements at the junction and at accessible external points. In large modules composed of thin chips and materials of high thermal conductivity the shape and distribution of the heat trajectories are influenced [...] Read more.
Traditionally the thermal behavior of power devices is characterized by temperature measurements at the junction and at accessible external points. In large modules composed of thin chips and materials of high thermal conductivity the shape and distribution of the heat trajectories are influenced by the external boundary represented by the cooling mount. This causes mediocre repeatability of the characteristic RthJC junction to case thermal resistance even in measurements at the same laboratory and causes very poor reproducibility among sites using dissimilar instrumentation. The Transient Dual Interface Methodology (TDIM) is based on the comparison of measured structure functions. With this method high repeatability can be achieved although introducing severe changes into the measurement environment is the essence of this test scheme. There is a systematic difference between thermal data measured with TDIM method and that measured with temperature probes, but we found that this difference was smaller than the scatter of the latter method. For checking production stability, we propose the use of a structure function-based Rth@Cth thermal metric, which is the thermal resistance value reached at the thermal capacitance belonging to the mass of the package base. This metric condenses the consistency of internal structural elements into a single number. Full article
(This article belongs to the Special Issue Thermal and Electro-thermal System Simulation 2020)
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18 pages, 2978 KiB  
Article
Thermal Modelling of a Prismatic Lithium-Ion Cell in a Battery Electric Vehicle Environment: Influences of the Experimental Validation Setup
by Jan Kleiner, Lidiya Komsiyska, Gordon Elger and Christian Endisch
Energies 2020, 13(1), 62; https://doi.org/10.3390/en13010062 - 20 Dec 2019
Cited by 29 | Viewed by 13649
Abstract
In electric vehicles with lithium-ion battery systems, the temperature of the battery cells has a great impact on performance, safety, and lifetime. Therefore, developing thermal models of lithium-ion batteries to predict and investigate the temperature development and its impact is crucial. Commonly, models [...] Read more.
In electric vehicles with lithium-ion battery systems, the temperature of the battery cells has a great impact on performance, safety, and lifetime. Therefore, developing thermal models of lithium-ion batteries to predict and investigate the temperature development and its impact is crucial. Commonly, models are validated with experimental data to ensure correct model behaviour. However, influences of experimental setups or comprehensive validation concepts are often not considered, especially for the use case of prismatic cells in a battery electric vehicle. In this work, a 3D electro–thermal model is developed and experimentally validated to predict the cell’s temperature behaviour for a single prismatic cell under battery electric vehicle (BEV) boundary conditions. One focus is on the development of a single cell’s experimental setup and the investigation of the commonly neglected influences of an experimental setup on the cell’s thermal behaviour. Furthermore, a detailed validation is performed for the laboratory BEV scenario for spatially resolved temperatures and heat generation. For validation, static and dynamic loads are considered as well as the detected experimental influences. The validated model is used to predict the temperature within the cell in the BEV application for constant current and Worldwide harmonized Light vehicles Test Procedure (WLTP) load profile. Full article
(This article belongs to the Special Issue Thermal and Electro-thermal System Simulation 2020)
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