Thermo-chemical model of the Pierce-Smith copper converter

A thermo-chemical model of the Pierce-Smith copper converter has been developed to predict the melt temperature. The primary assumption of the model was that all the matte, the slag, and the gaseous phases in the converter were in thermal and chemical equilibrium. In this model, the matte components considered were copper, iron, and sulphur elements. In the slag-making stage, all the reacted iron was converted to fayalite. On the basis of the model prediction and comparison with the plant data, the reaction rates of iron and oxygen in the slag-making stage and sulphur and oxygen in the blowing copper stage were assumed to be mixing controlled. The converter temperature was calculated by heat balance over time. The model was validated by detailed comparisons with measured industrial data. Good agreements between predicted and measured data were obtained. The results of parametric studies show that the melt temperature in the converter depends on the process parameters such as oxygen efficiency, melt emissivity, and oxygen enrichment. The results of this research can be used for process automation and optimizing.

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A Computer Model for Thermofluid Analysis of Vehicle Cooling Systems

ASME 1992 International Computers in Engineering Conference: Volume 1 — Artificial Intelligence; Expert Systems; CAD/CAM/CAE; Computers in Fluid Mechanics/Thermal Systems ◽

10.1115/cie1992-0063 ◽

1992 ◽

Author(s):

Alireza Veshagh ◽

Changyou Chen ◽

Richard Moffatt

Keyword(s):

Computer Model ◽

Individual Component ◽

Measured Data ◽

Test Cases ◽

Vehicle Model ◽

Cooling Systems ◽

Heating And Cooling ◽

Model Predictions ◽

Parametric Studies ◽

The Individual

Abstract This paper describes a computer model developed for analysing the thermofluid performance of vehicle cooling systems. The model has a modular structure which links various system submodels. The individual component submodels can be extended and modified in order to conduct parametric studies to examine the effects of various design and operating parameters on performance. The model can predict the overall thermal performance of the vehicle heating and cooling systems, providing useful information at the early stages of the design and development. In this paper, details of each submodel are described together with the overall structure of the vehicle model. The model predictions are compared with measured data and the application of the model is illustrated by several test cases.

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Application of Multiscale Crystal Plasticity Models to Forming Limit Diagrams

Journal of Engineering Materials and Technology ◽

10.1115/1.1753264 ◽

2004 ◽

Vol 126 (3) ◽

pp. 285-291 ◽

Cited By ~ 28

Author(s):

Robert D. McGinty ◽

David L. McDowell

Keyword(s):

Texture Evolution ◽

Sheet Thickness ◽

Rate Sensitivity ◽

Measured Data ◽

Forming Limit ◽

Initial Thickness ◽

Forming Limit Diagrams ◽

Polycrystal Plasticity ◽

Parametric Studies ◽

Initial Texture

A polycrystal plasticity model is used to conduct parametric studies of forming limit diagrams (FLD) and to compare with experimental data. The Marcinak and Kuczynski [13] method is applied. It is confirmed that the onset of necking is retarded by increases in the ratio of initial band to sheet thickness and material strain rate sensitivity. It was also demonstrated that initial texture plays an important role in FLD response, as has been shown in other recent studies [6,26,7]. It is shown that a texture resulting from plane strain compression to one-tenth of the initial thickness gives a predicted FLD that more closely matches measured data than that based on an initially isotropic texture. The influence of a relatively softer response in terms of effective stress in torsional shear than in compression (i.e., shear softening) on FLDs is investigated with the aid of a hardening surface formulation along with the polycrystal plasticity texture evolution model. It is shown that necking behavior can be significantly affected by shear softening, particularly for initially textured sheets. It is also demonstrated that the hardening surface formulation provides additional flexibility in modeling FLD behavior beyond that afforded by classical polycrystal plasticity.

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Verification of MPACT for the APR1400 Benchmark

Energies ◽

10.3390/en14133831 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3831

Author(s):

Kaitlyn Elizabeth Barr ◽

Sooyoung Choi ◽

Junsu Kang ◽

Brendan Kochunas

Keyword(s):

Nuclear Reactor ◽

Energy Systems ◽

Measured Data ◽

High Fidelity ◽

Monte Carlo Code ◽

Power Cycle ◽

Fuel Pin ◽

Parametric Studies ◽

Full Power ◽

Good Agreement

This paper describes benchmark calculations for the APR1400 nuclear reactor performed using the high-fidelity deterministic whole-core simulator MPACT compared to reference solutions generated by the Monte Carlo code McCARD. The methodology presented in this paper is a common approach in the field of nuclear reactor analysis, when measured data are not available for comparison, and may be more broadly applied in other simulation applications of energy systems. The benchmark consists of several problems that span the complexity of single pins to a hot full power cycle depletion. Overall, MPACT shows excellent agreement compared to the reference solutions. MPACT effectively predicts the reactivity for different geometries and several temperature and boron conditions. The largest deviation from McCARD occurs for cold zero conditions in which the fuel, moderator, and cladding are all 300 K. Possible reasons for this are discussed. Excluding these cases, the ρ reactivity difference from McCARD is consistently below 100 pcm. For single fuel pin problems, the highest error of 151 pcm occurs for the lowest fuel enrichment of 1.71 wt.% UO2, indicating possible, albeit small, enrichment bias in MPACT’s cross-section library. Furthermore, MOC and spatial mesh parametric studies indicate that default meshing parameters and options yield results comparable to finely meshed cases. Additionally, there is very good agreement of the radial and axial power distributions. RMS radial pin and assembly power differences for all cases are at or below 0.75%, and all RMS axial power differences are below 1.65%. These results are comparable to previous results from the VERA progression problems benchmark and meet generally accepted accuracy criteria for whole-core transport codes.

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RELAP5/MOD3.3 Analysis of the Loss of External Power Event with Safety Injection Actuation

Science and Technology of Nuclear Installations ◽

10.1155/2018/6964946 ◽

2018 ◽

Vol 2018 ◽

pp. 1-14

Author(s):

Andrej Prošek ◽

Marko Matkovič

Keyword(s):

Deep Understanding ◽

Simulated Data ◽

Computer Code ◽

Measured Data ◽

Plant Response ◽

Light Water Reactors ◽

External Power ◽

Plant Data ◽

Water Reactors ◽

Available Information

The code assessment typically comprises basic tests cases, separate effects test, and integral effects tests. On the other hand, the thermal hydraulic system codes like RELAP5/MOD3.3 are primarily intended for simulation of transients and accidents in light water reactors. The plant measured data come mostly from startup tests and operational events. Also, for operational events the measured plant data may not be sufficient to explain all details of the event. The purpose of this study was therefore besides code assessment to demonstrate that simulations can be very beneficial for deep understanding of the plant response and further corrective measures. The abnormal event with reactor trip and safety injection signal actuation was simulated with the latest RELAP5/MOD3.3 Patch 05 best-estimate thermal hydraulic computer code. The measured and simulated data agree well considering the major plant system responses and operator actions. This suggests that the RELAP5 code simulation is good representative of the plant response and can complement not available information from plant measured data. In such a way, an event can be better understood.

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RELAP5/MOD3.3 Code Validation with Plant Abnormal Event

Science and Technology of Nuclear Installations ◽

10.1155/2008/745178 ◽

2008 ◽

Vol 2008 ◽

pp. 1-10 ◽

Cited By ~ 2

Author(s):

Andrej Prošek ◽

Borut Mavko

Keyword(s):

Nuclear Power ◽

Calculated Data ◽

Computer Code ◽

Measured Data ◽

Power Reduction ◽

Code Validation ◽

Periodic Testing ◽

Plant Data ◽

Input Model

Measured plant data from various abnormal events are of great importance for code validation. The purpose of the study was to validate the RELAP5/MOD3.3 Patch 03 computer code with the abnormal event which occurred at Krško Nuclear Power Plant (NPP) on April 10, 2005. The event analyzed was a malfunction, which occurred during a power reduction sequence when regular periodic testing of the turbine valves was performed. Unexpected turbine valve closing caused safety injection signal, followed by reactor trip. The RELAP5 input model delivered by Krško NPP was used. In short term, the calculation agrees very well with the plant measured data. In the long term, this is also true when operator actions and special plant systems are modeled. In the opposite, the transient would progress quite differently. Finally, the calculated data may be supplemental to plant measured data when the information is missing or the measurement is questionable.

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RELAP5-3D Code Validation for RBMK-1500 Reactors

12th International Conference on Nuclear Engineering, Volume 3 ◽

10.1115/icone12-49122 ◽

2004 ◽

Cited By ~ 2

Author(s):

Evaldas Bubelis ◽

Algirdas Kaliatka ◽

Eugenijus Uspuras

Keyword(s):

Reasonable Agreement ◽

3D Model ◽

Reactor Core ◽

Measured Data ◽

Primary Circuit ◽

Hydraulic Parameters ◽

Physical Processes ◽

Code Validation ◽

Calculation Results ◽

Plant Data

This paper deals with RELAP5-3D code validation through the modeling of RBMK-1500 specific transients taking place at Ignalina NPP. A successful best estimate RELAP5-3D model of the INPP RBMK-1500 reactor has been developed and validated against real plant data. The obtained calculation results demonstrate reasonable agreement with Ignalina NPP measured data. Behaviors of the separate MCC thermal-hydraulic parameters as well as physical processes are predicted reasonably well to the real processes, occurring in the primary circuit of RBMK-1500 reactor. The calculated reactivity and the total reactor core power behavior in time are also in reasonable agreement with the measured plant data, which demonstrates the correct modeling of the neutronic processes taking place in RBMK-1500 reactor core. The performed validation of RELAP5-3D model of Ignalina NPP RBMK-1500 reactor allowed to improve the model, which in the future would be used for the safety substantiation calculations of RBMK-1500 reactors.

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SEM analysis of the change in the reaction rates with deposit structures in the copper-iron cementation system

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100109422 ◽

1978 ◽

Vol 36 (1) ◽

pp. 456-457

Author(s):

V. Annamalai ◽

L.E. Murr

Keyword(s):

Structural Characteristics ◽

Secondary Electron Emission ◽

Copper Deposit ◽

Reaction Rates ◽

Sem Analysis ◽

Experimental Conditions ◽

Major Drawback ◽

Emission Mode ◽

Scrap Iron ◽

Image Position

Economical recovery of copper metal from leach liquors has been carried out by the simple process of cementing copper onto a suitable substrate metal, such as scrap-iron, since the 16th century. The process has, however, a major drawback of consuming more iron than stoichiometrically needed by the reaction.Therefore, many research groups started looking into the process more closely. Though it is accepted that the structural characteristics of the resultant copper deposit cause changes in reaction rates for various experimental conditions, not many systems have been systematically investigated. This paper examines the deposit structures and the kinetic data, and explains the correlations between them.A simple cementation cell along with rotating discs of pure iron (99.9%) were employed in this study to obtain the kinetic results The resultant copper deposits were studied in a Hitachi Perkin-Elmer HHS-2R scanning electron microscope operated at 25kV in the secondary electron emission mode.

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Dynamic studies of silicide-mediated crystallization of amorphous silicon

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100131395 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1352-1353

Author(s):

C. Hayzelden ◽

J. L. Batstone

Keyword(s):

Ion Implantation ◽

Solid Phase ◽

Metallic Phase ◽

Single Crystal Substrate ◽

Free Electrons ◽

Melt Temperature ◽

Transmission Electron ◽

Crystal Substrate ◽

High Resolution Tem

Epitaxial reordering of amorphous Si(a-Si) on an underlying single-crystal substrate occurs well below the melt temperature by the process of solid phase epitaxial growth (SPEG). Growth of crystalline Si(c-Si) is known to be enhanced by the presence of small amounts of a metallic phase, presumably due to an interaction of the free electrons of the metal with the covalent Si bonds near the growing interface. Ion implantation of Ni was shown to lower the crystallization temperature of an a-Si thin film by approximately 200°C. Using in situ transmission electron microscopy (TEM), precipitates of NiSi2 formed within the a-Si film during annealing, were observed to migrate, leaving a trail of epitaxial c-Si. High resolution TEM revealed an epitaxial NiSi2/Si(l11) interface which was Type A. We discuss here the enhanced nucleation of c-Si and subsequent silicide-mediated SPEG of Ni-implanted a-Si.Thin films of a-Si, 950 Å thick, were deposited onto Si(100) wafers capped with 1000Å of a-SiO2. Ion implantation produced sharply peaked Ni concentrations of 4×l020 and 2×l021 ions cm−3, in the center of the films.

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