Automatic Thermal Modeling for System Level Design of Electronic Equipment

2003 ◽  
Author(s):  
Kenichiro Aoki ◽  
Koichi Shimizu ◽  
Akira Ueda ◽  
Akira Tamura ◽  
Masanori Motegi
Keyword(s):  
Model Building ◽  
Software Tool ◽  
System Level ◽  
Analysis Model ◽  
Accurate Analysis ◽  
Fluid Analysis ◽  
Analytical Accuracy ◽  
Thermal Fluid Analysis ◽  
Short Time ◽  
Large Investment

The development of hardware needs cost reduction by shortening a development period and reducing experimental man-hour. In order to satisfy these demands, thermal fluid analysis with higher accuracy in short time is indispensable for product development. At present, thermal fluid analyses are conducted using different software tools. Each software tool requires model building and meshing for simulations using its own format. That leads to a large investment in time, and therefore cost. VPS/Simulation-Hub software Fujitsu developed is able to convert data from various CADs. It has the features to create a data fitting to numerical analysis software, create an accurate analysis model, and delete unnecessary components. With these main features, VPS/Simulation-Hub greatly contributes to the man-hour reduction for model building and the improvement of analytical accuracy. In this paper, VPS/Simulation-Hub is introduced with the detail explanation of the above 3 main features.

scholarly journals Architecture choices for high-temperature synchronous machines

Open Physics ◽  
2020 ◽  
Vol 18 (1) ◽  
pp. 683-700
Author(s):  
Ewa Napieralska Juszczak ◽  
Daniel Roger ◽  
Krzysztof Komeza ◽  
Marcin Lefik ◽  
Piotr Napieralski
Keyword(s):  
Temperature Limit ◽  
Synchronous Machines ◽  
Permanent Magnet Synchronous Machine ◽  
Analysis Model ◽  
Synchronous Reluctance Machine ◽  
Fluid Analysis ◽  
Reluctance Machine ◽  
Electromagnetic Fluid ◽  
Simulation Results ◽  
Thermal Fluid Analysis

AbstractThe article proposes an analysis of the possible architectures of synchronous machines with an ability to operate at high temperatures of over 200°C in their environment. Two machine principles have been considered: the permanent magnet synchronous machine and the synchronous reluctance machine. The numerical analyses are carried out with 3D-coupled electromagnetic-fluid-thermal models; the electromagnetic one provides the local losses that give the input data to the coupled thermal-fluid analysis model for computing the temperatures inside the machines. The simulation results are used for estimating the temperature limit of each machine architecture, considering the characteristics of their critical parts.

scholarly journals DEVELOPMENT OF PIN-LEVEL NEUTRONICS/THERMAL-FLUID ANALYSIS COUPLED CODE SYSTEM FOR A BLOCK-TYPE HTGR CORE

2021 ◽  
Vol 247 ◽  
pp. 02041
Author(s):  
Yuk Seungsu ◽  
Tak Nam-il ◽  
Chang Jo Keun
Keyword(s):  
Power Distribution ◽  
Large Change ◽  
Maximum Temperature ◽  
Distribution Data ◽  
Block Type ◽  
High Fidelity ◽  
Code System ◽  
Accurate Analysis ◽  
Fluid Analysis ◽  
Thermal Fluid Analysis

Recently, the coupling between computer codes that simulate different physical phenomena has attracted for more accurate analysis. In the case of high-temperature gas-cooled reactor (HTGR), the coupling between neutronics and thermal-fluid analysis is necessary because of large change of temperature in the reactor core. Korea Atomic Energy Research Institute (KAERI) has developed the coupled code system between a reactor physics analysis code CAPP and a thermal-fluid system safety analysis code GAMMA+ for a block-type HTGR. The CAPP/GAMMA+ coupled code system provides more accurate block-wise distribution data than CAPP or GAMMA+ stand-alone analysis. However, the block-wise distribution data has the limitation in order to predict safety parameters such as the maximum temperature of the nuclear fuel. It is necessary to calculate refined distribution, for example, pin-level (fuel compact level) distribution. In this study, we tried to solve this problem by coupling CAPP and a high-fidelity thermal-fluid analysis code CORONA. CORONA can perform a high-fidelity thermal-fluid analysis of Computational Fluid Dynamics (CFD) level by dividing a block-type HTGR core into small lattices. On the other hand, CAPP can provide a pin power distribution. It is expected that the refined, more accurate distribution data for a block-type HTGR can be obtained by coupling these two codes. This paper presents the development of coupled code system between CAPP and CORONA, and then it is tested on a simple HTGR column problem with encouraging results.

scholarly journals Testing algorithm for heat transfer performance of nanofluid-filled heat pipe based on neural network

Open Physics ◽  
2020 ◽  
Vol 18 (1) ◽  
pp. 751-760
Author(s):  
Lei Lei
Keyword(s):  
Neural Network ◽  
Heat Transfer ◽  
Heat Pipe ◽  
Heat Transfer Performance ◽  
Volume Fraction ◽  
Heat Pipes ◽  
Transfer Performance ◽  
Analysis Model ◽  
Accurate Analysis ◽  
Testing Algorithm

AbstractTraditional testing algorithm based on pattern matching is impossible to effectively analyze the heat transfer performance of heat pipes filled with different concentrations of nanofluids, so the testing algorithm for heat transfer performance of a nanofluidic heat pipe based on neural network is proposed. Nanofluids are obtained by weighing, preparing, stirring, standing and shaking using dichotomy. Based on this, the heat transfer performance analysis model of the nanofluidic heat pipe based on artificial neural network is constructed, which is applied to the analysis of heat transfer performance of nanofluidic heat pipes to achieve accurate analysis. The experimental results show that the proposed algorithm can effectively analyze the heat transfer performance of heat pipes under different concentrations of nanofluids, and the heat transfer performance of heat pipes is best when the volume fraction of nanofluids is 0.15%.

scholarly journals AERIAL PHOTOGRAPHIC WATERLINE SURVEY OF AN ESTUARY

1974 ◽  
Vol 1 (14) ◽  
pp. 148
Author(s):  
J. SIndern ◽  
G.E. Schroder
Keyword(s):  
Tide Gauge ◽  
High Water ◽  
Aerial Photographs ◽  
Northern Germany ◽  
Tide Gauge Records ◽  
Time Intervals ◽  
Accurate Analysis ◽  
Contour Lines ◽  
Short Time ◽  
Reference Markers

The project of a "barrage across an estuary in Northern Germany was accompanied by a programme to monitor the hydrologic and morphologic situation. This became necessary in order to avoid dangers resulting from the sensitivity of the shallow wadden area to human interference. Various methods to record the morphology were tested. The aerial photographic waterline survey proved superior as it supplies a complete and economic record and allows accurate analysis of the topography. The principle consists in taking aerial photographs at short time intervals between low water and high water, each photo showing a different waterline. The scale chosen was 1:18000, corresponding to a flight altitude of 2700 metres. Rectification of the distorted photos requires reference markers to be distributed over the survey area which measures about 140 km^. By using simultaneous tide gauge records, contour lines can be constructed from the photographed waterlines. This morphologic record is supplemented by submarine survey of the estuary. It is expected that details of sediment transport and of tidal prism changes may be revealed. Predicted and actual effects of the barrage will be compared, which might lead to a better understanding of such coasts.

scholarly journals A Coupled, Semi-Numerical Model for Thermal Analysis of Medium Frequency Transformer

Energies ◽  
2019 ◽  
Vol 12 (2) ◽  
pp. 328 ◽  
Author(s):  
Haonan Tian ◽  
Zhongbao Wei ◽  
Sriram Vaisambhayana ◽  
Madasamy Thevar ◽  
Anshuman Tripathi ◽  
...  
Keyword(s):  
Numerical Model ◽  
Analytical Model ◽  
Electromagnetic Analysis ◽  
Medium Frequency ◽  
Fluid Analysis ◽  
Fluid Behavior ◽  
Proposed Model ◽  
Computational Fluid Dynamics Cfd ◽  
Cfd Method ◽  
Thermal Fluid Analysis

Medium-frequency (MF) transformer has gained much popularity in power conversion systems. Temperature control is a paramount concern, as the unexpected high temperature declines the safety and life expectancy of transformer. The scrutiny of losses and thermal-fluid behavior are thereby critical for the design of MF transformers. This paper proposes a coupled, semi-numerical model for electromagnetic and thermal-fluid analysis of MF oil natural air natural (ONAN) transformer. An analytical model that is based on spatial distribution of flux density and AC factor is exploited to calculate the system losses, while the thermal-hydraulic behavior is modelled numerically leveraging the computational fluid dynamics (CFD) method. A close-loop iterative framework is formulated by coupling the analytical model-based electromagnetic analysis and CFD-based thermal-fluid analysis to address the temperature dependence. Experiments are performed on two transformer prototypes with different conductor types and physical geometries for validation purpose. Results suggest that the proposed model can accurately model the AC effects, losses, and the temperature rises at different system components. The proposed model is computationally more efficient than the full numerical method but it reserves accurate thermal-hydraulic characterization, thus it is promising for engineering utilization.

scholarly journals Investigating system-level drivers of obesity with adolescents: a group model-building exercise

The Lancet ◽  
2019 ◽  
Vol 394 ◽  
pp. S83
Author(s):  
Natalie Savona ◽  
Cécile Knai ◽  
Talia Macauley
Keyword(s):  
Model Building ◽  
System Level ◽  
Group Model ◽  
Group Model Building

scholarly journals Developing Data Mining-Based Prognostic Models for CF-18 Aircraft

2010 ◽  
Author(s):  
Marvin Zaluski ◽  
Sylvain Le´tourneau ◽  
Jeff Bird ◽  
Chunsheng Yang
Keyword(s):  
Data Mining ◽  
Model Building ◽  
Health Management ◽  
Model Development ◽  
Data Gathering ◽  
Software Tool ◽  
Prognostic Models ◽  
Canadian Forces ◽  
Fusion Data ◽  
Operating Organization

The CF-18 aircraft is a complex system for which a variety of data are systematically being recorded: operational flight data from sensors and Built-In Test Equipment (BITE) and maintenance activities recorded by personnel. These data resources are stored and used within the operating organization but new analytical and statistical techniques and tools are being developed that could be applied to these data to benefit the organization. This paper investigates the utility of readily available CF-18 data to develop data mining-based models for prognostics and health management (PHM) systems. We introduce a generic data mining methodology developed to build prognostic models from operational and maintenance data and elaborate on challenges specific to the use of CF-18 data from the Canadian Forces. We focus on a number of key data mining tasks including: data gathering, information fusion, data pre-processing, model building, and evaluation. The solutions developed to address these tasks are described. A software tool developed to automate the model development process is also presented. Finally, the paper discusses preliminary results on the creation of models to predict F404 No. 4 Bearing and MFC (Main Fuel Control) failures on the CF-18.

Software tool for simulation of vehicle – road interaction

2017 ◽  
Vol 34 (5) ◽  
pp. 1501-1526 ◽  
Author(s):  
Francisco Duarte ◽  
Adelino Ferreira ◽  
Paulo Fael
Keyword(s):  
Great Influence ◽  
Software Tool ◽  
Energy Harvest ◽  
Energetic Efficiency ◽  
Analysis Model ◽  
Content Type ◽  
Speed Reduction ◽  
The Road ◽  
Car Model ◽  
Road Pavement

Purpose This paper aims to deal with the development of a software tool to simulate and study vehicle – road interaction (VRI) to quantify the forces induced and energy released from vehicles to the road pavement, in different vehicle motion scenarios, and the energy absorbed by the road surface, speed reducers or a specific energy harvester surface or device. The software tool also enables users to quantify the energetic efficiency of the process. Design/methodology/approach Existing software tools were analysed and its limitations were identified in terms of performing energetic analysis on the interaction between the vehicle and the road pavement elements, such as speed reducers or energy harvest devices. The software tool presented in this paper intends to overcome those limitations and precisely quantify the energy transfer. Findings Different vehicle models and VRI models were evaluated, allowing to conclude about each model precision: bicycle car model has a 60 per cent higher precision when compared with quarter-car model, and contact patch analysis model has a 67 per cent higher precision than single force analysis model. Also, a technical study was performed for different equipment surface shapes and displacements, concluding that these variables have a great influence on the energy released by the vehicle and on the energy harvested by the equipment surface. Originality/value The developed software tool allows to study VRI with a higher precision than existing tools, especially when energetic analyses are performed and when speed reduction or energy harvesting devices are applied on the pavement.

Sign in / Sign up

Export Citation Format

Share Document