Exergoeconomic analysis of a Peltier effect air cooler using experimental data

This paper develops a model to simulate wire-to-sheet lapped resistance microwelding (RMW) process. The model employs a coupled thermal–electrical–mechanical analysis and accounts for temperature-dependent thermophysical properties of materials, contact resistance and the Peltier effect. Results show the interface temperature between the molybdenum electrode and copper wire is higher than the faying surface. The predicted thermal distributes agree well with the experimental data. The proposed model can be applied to predict the effects of the welding parameters.

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A mathematical modelling of frost growth dynamics on a surface of fin-and-tube air cooler

MATEC Web of Conferences ◽

10.1051/matecconf/202032402005 ◽

2020 ◽

Vol 324 ◽

pp. 02005

Author(s):

Boris T. Marinyuk ◽

Sergei V. Belukov ◽

Igor A. Korolev

Keyword(s):

Heat Transfer ◽

Experimental Data ◽

Heat Transfer Coefficient ◽

Transfer Coefficient ◽

Aerodynamic Resistance ◽

Growth Dynamics ◽

Cooling Capacity ◽

Operating Conditions ◽

Overall Heat Transfer Coefficient ◽

Air Cooler

A mathematical model was developed to predict the performance characteristics of fin-and-tube air coolers with plane fins, taking into account the temperature and humidity conditions, non-uniform thickness of the frost layer along the heat exchanger core, flow-pressure characteristics of the fans and the refrigerant superheat zone. The model was verified on the experimental data of air cooler performance in frosting conditions obtained by the authors in air temperature range from minus 6 to minus 20 ° C, and experimental data from independent researchers. The presented model predicts the cooling capacity and the overall heat transfer coefficient in the evaporator with error not exceeded 15%. It was found that during dry operating conditions of the air cooler, the refrigerant boiling temperature descent by 10 °C leads to a decrease in the overall heat transfer coefficient by 35%. The main reason of that is double decrease of the refrigerant mass velocity and the refrigerant-side heat transfer coefficient by 75%. The process of frost grow leads to an increase in overall thermal resistance in the studied air cooler by 30%, more than double increase in the aerodynamic resistance and decrease in cooling capacity by 15%.

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Microdiffraction Patterns of Small Metallic Particles II; Theoretical Analysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100055680 ◽

1982 ◽

Vol 40 ◽

pp. 668-669

Author(s):

A. Gómez ◽

P. Schabes-Retchkiman ◽

M. José-Yacamán ◽

T. Ocaña

Keyword(s):

Experimental Data ◽

Electron Diffraction ◽

Theoretical Analysis ◽

Size Range ◽

Dynamical Theory ◽

Metallic Particles ◽

Splitting Effect

The splitting effect that is observed in microdiffraction pat-terns of small metallic particles in the size range 50-500 Å can be understood using the dynamical theory of electron diffraction for the case of a crystal containing a finite wedge. For the experimental data we refer to part I of this work in these proceedings.

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Evidence for ordered Fe3Ni

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100125981 ◽

1987 ◽

Vol 45 ◽

pp. 216-217

Author(s):

K.B. Reuter ◽

D.B. Williams ◽

J.I. Goldstein

Keyword(s):

Experimental Data ◽

Martensitic Transformation ◽

Electron Diffraction ◽

Room Temperature ◽

Direct Evidence ◽

Transformation Product ◽

Iron Meteorites ◽

X Ray ◽

Ni Content ◽

Temperature Transformation

In the Fe-Ni system, although ordered FeNi and ordered Ni3Fe are experimentally well established, direct evidence for ordered Fe3Ni is unconvincing. Little experimental data for Fe3Ni exists because diffusion is sluggish at temperatures below 400°C and because alloys containing less than 29 wt% Ni undergo a martensitic transformation at room temperature. Fe-Ni phases in iron meteorites were examined in this study because iron meteorites have cooled at slow rates of about 10°C/106 years, allowing phase transformations below 400°C to occur. One low temperature transformation product, called clear taenite 2 (CT2), was of particular interest because it contains less than 30 wtZ Ni and is not martensitic. Because CT2 is only a few microns in size, the structure and Ni content were determined through electron diffraction and x-ray microanalysis. A Philips EM400T operated at 120 kV, equipped with a Tracor Northern 2000 multichannel analyzer, was used.

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EELS white line intensities calculated for the 3d and 4d metals

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100153919 ◽

1989 ◽

Vol 47 ◽

pp. 388-389

Author(s):

C. C. Ahn ◽

D. H. Pearson ◽

P. Rez ◽

B. Fultz

Keyword(s):

Experimental Data ◽

Line Intensity ◽

Transition Probabilities ◽

Initial Increase ◽

White Line ◽

Hartree Fock ◽

Line Intensities ◽

Integrated Intensity ◽

X Ray Absorption ◽

The Continuum

Previous experimental measurements of the total white line intensities from L2,3 energy loss spectra of 3d transition metals reported a linear dependence of the white line intensity on 3d occupancy. These results are inconsistent, however, with behavior inferred from relativistic one electron Dirac-Fock calculations, which show an initial increase followed by a decrease of total white line intensity across the 3d series. This inconsistency with experimental data is especially puzzling in light of work by Thole, et al., which successfully calculates x-ray absorption spectra of the lanthanide M4,5 white lines by employing a less rigorous Hartree-Fock calculation with relativistic corrections based on the work of Cowan. When restricted to transitions allowed by dipole selection rules, the calculated spectra of the lanthanide M4,5 white lines show a decreasing intensity as a function of Z that was consistent with the available experimental data.Here we report the results of Dirac-Fock calculations of the L2,3 white lines of the 3d and 4d elements, and compare the results to the experimental work of Pearson et al. In a previous study, similar calculations helped to account for the non-statistical behavior of L3/L2 ratios of the 3d metals. We assumed that all metals had a single 4s electron. Because these calculations provide absolute transition probabilities, to compare the calculated white line intensities to the experimental data, we normalized the calculated intensities to the intensity of the continuum above the L3 edges. The continuum intensity was obtained by Hartree-Slater calculations, and the normalization factor for the white line intensities was the integrated intensity in an energy window of fixed width and position above the L3 edge of each element.

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On the Meta-Analysis of Nonrandom, Quasi-Experimental Data

PsycEXTRA Dataset ◽

10.1037/e518392013-139 ◽

2010 ◽

Author(s):

Richard N. Landers

Keyword(s):

Experimental Data ◽

Meta Analysis ◽

Quasi Experimental

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A fuzzy neural network approach for modeling the growth kinetics of FeB and Fe2B layers during the boronizing process

Matériaux & Techniques ◽

10.1051/mattech/2019002 ◽

2018 ◽

Vol 106 (6) ◽

pp. 603 ◽

Cited By ~ 2

Author(s):

Bendaoud Mebarek ◽

Mourad Keddam

Keyword(s):

Neural Network ◽

Experimental Data ◽

Fuzzy Neural Network ◽

Treatment Time ◽

Calculation Model ◽

Average Error ◽

Network Approach ◽

Neural Network Approach ◽

Fuzzy Neural ◽

Kinetics Of

In this paper, we develop a boronizing process simulation model based on fuzzy neural network (FNN) approach for estimating the thickness of the FeB and Fe2B layers. The model represents a synthesis of two artificial intelligence techniques; the fuzzy logic and the neural network. Characteristics of the fuzzy neural network approach for the modelling of boronizing process are presented in this study. In order to validate the results of our calculation model, we have used the learning base of experimental data of the powder-pack boronizing of Fe-15Cr alloy in the temperature range from 800 to 1050 °C and for a treatment time ranging from 0.5 to 12 h. The obtained results show that it is possible to estimate the influence of different process parameters. Comparing the results obtained by the artificial neural network to experimental data, the average error generated from the fuzzy neural network was 3% for the FeB layer and 3.5% for the Fe2B layer. The results obtained from the fuzzy neural network approach are in agreement with the experimental data. Finally, the utilization of fuzzy neural network approach is well adapted for the boronizing kinetics of Fe-15Cr alloy.

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Use of Posterior Probabilities to Evaluate Methods of Discriminant Analysis

Methods of Information in Medicine ◽

10.1055/s-0038-1635316 ◽

1981 ◽

Vol 20 (04) ◽

pp. 207-212 ◽

Cited By ~ 6

Author(s):

J. Hermans ◽

B. van Zomeren ◽

J. W. Raatgever ◽

P. J. Sterk ◽

J. D. F. Habbema

Keyword(s):

Experimental Data ◽

Discriminant Analysis ◽

Posterior Probabilities

By means of a case study the choice between several methods of discriminant analysis is presented. Experimental data of a two-groups problem with one or two variables is analysed. The different methods are compared according to posterior probabilities which can be computed for each subject and which are the basis of discriminant analysis. These posterior probabilities are analysed graphically as well as numerically.

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Analysis of athletes’ stadium stress source based on improved layered K-means algorithm

Journal of Intelligent & Fuzzy Systems ◽

10.3233/jifs-189065 ◽

2020 ◽

Vol 39 (4) ◽

pp. 5905-5914

Author(s):

Chen Gong

Keyword(s):

Experimental Data ◽

Machine Learning Algorithms ◽

User Preference ◽

Experimental Comparison ◽

Actual Situation ◽

Medical Field ◽

Pressure Source ◽

Preference Model ◽

Related Research ◽

Analysis System

Most of the research on stressors is in the medical field, and there are few analysis of athletes’ stressors, so it can not provide reference for the analysis of athletes’ stressors. Based on this, this study combines machine learning algorithms to analyze the pressure source of athletes’ stadium. In terms of data collection, it is mainly obtained through questionnaire survey and interview form, and it is used as experimental data after passing the test. In order to improve the performance of the algorithm, this paper combines the known K-Means algorithm with the layering algorithm to form a new improved layered K-Means algorithm. At the same time, this paper analyzes the performance of the improved hierarchical K-Means algorithm through experimental comparison and compares the clustering results. In addition, the analysis system corresponding to the algorithm is constructed based on the actual situation, the algorithm is applied to practice, and the user preference model is constructed. Finally, this article helps athletes find stressors and find ways to reduce stressors through personalized recommendations. The research shows that the algorithm of this study is reliable and has certain practical effects and can provide theoretical reference for subsequent related research.

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Exergoeconomic analysis of renewable multi-generation system

WEENTECH Proceedings in Energy ◽

10.32438/wpe.1920 ◽

2020 ◽

pp. 99-111

Author(s):

Vontas Alfenny Nahan ◽

Audrius Bagdanavicius ◽

Andrew McMullan

Keyword(s):

Capital Investment ◽

Combined Cycle ◽

Asian Countries ◽

Generation System ◽

Integrated Gasification Combined Cycle ◽

Heating And Cooling ◽

Integrated Gasification ◽

Exergoeconomic Analysis ◽

Main Components ◽

The Cost

In this study a new multi-generation system which generates power (electricity), thermal energy (heating and cooling) and ash for agricultural needs has been developed and analysed. The system consists of a Biomass Integrated Gasification Combined Cycle (BIGCC) and an absorption chiller system. The system generates about 3.4 MW electricity, 4.9 MW of heat, 88 kW of cooling and 90 kg/h of ash. The multi-generation system has been modelled using Cycle Tempo and EES. Energy, exergy and exergoeconomic analysis of this system had been conducted and exergy costs have been calculated. The exergoeconomic study shows that gasifier, combustor, and Heat Recovery Steam Generator are the main components where the total cost rates are the highest. Exergoeconomic variables such as relative cost difference (r) and exergoeconomic factor (f) have also been calculated. Exergoeconomic factor of evaporator, combustor and condenser are 1.3%, 0.7% and 0.9%, respectively, which is considered very low, indicates that the capital cost rates are much lower than the exergy destruction cost rates. It implies that the improvement of these components could be achieved by increasing the capital investment. The exergy cost of electricity produced in the gas turbine and steam turbine is 0.1050 £/kWh and 0.1627 £/kWh, respectively. The cost of ash is 0.0031 £/kg. In some Asian countries, such as Indonesia, ash could be used as fertilizer for agriculture. Heat exergy cost is 0.0619 £/kWh for gasifier and 0.3972 £/kWh for condenser in the BIGCC system. In the AC system, the exergy cost of the heat in the condenser and absorber is about 0.2956 £/kWh and 0.5636 £/kWh, respectively. The exergy cost of cooling in the AC system is 0.4706 £/kWh. This study shows that exergoeconomic analysis is powerful tool for assessing the costs of products.

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