scholarly journals Analysis of Errors in Simulation Modeling

2021 ◽  
Author(s):  
Hiram Martinez Muñoz
Keyword(s):  
Heat Treatment ◽  
Induction Heating ◽  
Induction Hardening ◽  
Physical Parameters ◽  
Single Shot ◽  
Finite Elements Analysis ◽  
Heavy Load ◽  
Simulation Tools ◽  
Half Loop ◽  
Set Up

Abstract Nowadays, the use of technologies to increase productivity, reduce time, as well as reduce the possibilities of errors, has become indispensable. All processes have opportunities for improvement, and this can be done based on calculations that with the support of computational systems can be reduced considerably in time. In the heat treatment industry and more specifically in the electromagnetic induction heat treatment industry is no exception. Today we have numerous tools to optimize the design process of inductors used in heat treatment of metals. These tools can show us, in a virtual way, the results that we can obtain before having to manufacture the inductors, all this based on FEA (Finite Elements Analysis) simulations that performing calculations considering physical parameters approximate us to what we would have as a result. Computer based simulation programs for induction heating and resulting metallurgy are extremely useful in developing tooling and process for induction heating. Induction hardening simulation brings elements of inductor design, steel properties such as time-temperature-transformation curves, both thermal and magnetic properties at various temperatures and cooling rates based on the phase of the quench media on cooling. A common method in place hardening (static hardening) knows as single shot hardening. In this process, the inductor is designed with a top and bottom half loop connected by heating rails. The length of heating is determined by the length of the rails and percentage height of the width of the half loops. Accurately predicting the length of the heating pattern in this 3D modeling approach is computationally a heavy load on the modeling pre-requisites. Commonly the inductor is modeled and then tested with the actual results showing a different length than what was predicted. It is important to consider that like any system, these simulation tools are not infallible and have several factors that can affect the accuracy of the simulation results. This paper reaches into the analysis of why the predicted length may differ prom the test results discussing what factors constitute the largest variance from the predicted outcome. Inductor design and the reliance on set up will be discussed.

scholarly journals A 2-D model for Intermediate Temperature Solid Oxide Fuel Cells Preliminarily Validated on Local Values

Catalysts ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 36 ◽  
Author(s):  
Bruno Conti ◽  
Barbara Bosio ◽  
Stephen John McPhail ◽  
Francesca Santoni ◽  
Davide Pumiglia ◽  
...  
Keyword(s):  
Fuel Cells ◽  
Operating Conditions ◽  
Solid Oxide ◽  
Intermediate Temperature ◽  
Physical Parameters ◽  
Local Concentration ◽  
Oxide Fuel ◽  
Molten Carbonate ◽  
Experimental Apparatus ◽  
Set Up

Intermediate Temperature Solid Oxide Fuel Cell (IT-SOFC) technology offers interesting opportunities in the panorama of a larger penetration of renewable and distributed power generation, namely high electrical efficiency at manageable scales for both remote and industrial applications. In order to optimize the performance and the operating conditions of such a pre-commercial technology, an effective synergy between experimentation and simulation is fundamental. For this purpose, starting from the SIMFC (SIMulation of Fuel Cells) code set-up and successfully validated for Molten Carbonate Fuel Cells, a new version of the code has been developed for IT-SOFCs. The new release of the code allows the calculation of the maps of the main electrical, chemical, and physical parameters on the cell plane of planar IT-SOFCs fed in co-flow. A semi-empirical kinetic formulation has been set-up, identifying the related parameters thanks to a devoted series of experiments, and integrated in SIMFC. Thanks to a multi-sampling innovative experimental apparatus the simultaneous measurement of temperature and gas composition on the cell plane was possible, so that a preliminary validation of the model on local values was carried out. A good agreement between experimental and simulated data was achieved in terms of cell voltages and local temperatures, but also, for the first time, in terms of local concentration on the cell plane, encouraging further developments. This numerical tool is proposed for a better interpretation of the phenomena occurring in IT-SOFCs and a consequential optimization of their performance.

Application of Tailored Heat Treated Blanks under Quasi Series Conditions

2007 ◽  
Vol 344 ◽  
pp. 383-390 ◽  
Author(s):  
Marion Merklein ◽  
Uwe Vogt
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Local Heat ◽  
Strength Distribution ◽  
Process Window ◽  
Short Term ◽  
Forming Process ◽  
Heat Treated ◽  
Set Up ◽  
The Impact

Tailored Heat Treated Blanks (THTB) are blanks that exhibit locally different strength specifically optimized for the succeeding forming process. The strength distribution is set by a local, short-term heat treatment modifying the mechanical properties of the material. Hence, THTB allow enhancing forming limits significantly leading to shorter and more robust manufacture process chains. In order to qualify the use of THTB under quasi series conditions, the interdependencies of the blank’s local heat treatment and the entire process chain of the car body manufacture have to be analyzed. In this respect, the impact of a short-term heat treatment on the mechanical properties of AA6181PX, a commonly used aluminum alloy in today’s car bodies, was studied. Also the influence of a short-term heat treatment on the coil lubricant, usually already applied by the material supplier, was given a closer look. Based on these experiments process restrictions for the application of THTB in an industrial automotive environment were derived and a process window for the THTB design was set up. In conclusion, strategies were defined how to enhance the found process boundaries leading to a more robust process window.

Advantages of Induction Heat Treatment in the Application of Self-Fluxing Alloy to Boiler Tubes

1998 ◽  
Author(s):  
A. Tomiguchi ◽  
Y. Sochi ◽  
Y. Matsubara
Keyword(s):  
Heat Treatment ◽  
Service Life ◽  
Induction Heating ◽  
Corrosion And Wear ◽  
Hard Coatings ◽  
Heating Process ◽  
Induction Heat ◽  
Induction Heat Treatment ◽  
Boiler Tubes ◽  
Bent Pipe

Abstract This study focuses on two major advantages of induction heating over flame heating in the treatment of coated boiler tubes. In both cases the induction heating process is simple, fast and effective. Firstly, we will show how the the use of induction heating results in exceptionally thick and hard coatings with low porosity. Having high corrosion and wear resistant properties, the products can satisfy industry's needs for reliable coatings with a long service life. Next, the study will detail how a pipe with the coating already applied can be simultaneously bent by induction heating while the coating is melted and fused to the pipe. The result is a thicker, more even and reliable coating than that accomplished by the flame sprayed method on a bent pipe. The process is not only less cumbersome, but again provides a superior product for the market.

scholarly journals A Study of the Stability of a Plate-Like Load Towed beneath a Helicopter

1971 ◽  
Vol 13 (5) ◽  
pp. 330-343 ◽  
Author(s):  
D. F. Sheldon
Keyword(s):  
Equations Of Motion ◽  
Physical Parameters ◽  
Recent Experience ◽  
Wind Tunnel Testing ◽  
Stability Derivatives ◽  
Direct Indication ◽  
Metric Dimensions ◽  
Set Up ◽  
The Stability ◽  
Derivative Information

Recent experience has shown that a plate-like load suspended beneath a helicopter moving in horizontal forward flight has unstable characteristics at both low and high forward speeds. These findings have prompted a theoretical analysis to determine the longitudinal and lateral dynamic stability of a suspended pallet. Only the longitudinal stability is considered here. Although it is strictly a non-linear problem, the usual assumptions have been made to obtain linearized equations of motion. The aerodynamic derivative data required for these equations have been obtained, where possible, for the appropriate ranges of Reynolds and Strouhal number by means of static and dynamic wind tunnel testing. The resulting stability equations (with full aerodynamic derivative information) have been set up and solved, on a digital computer, to give direct indication of a stable or unstable system for a combination of physical parameters. These results have indicated a longitudinal unstable mode for all practical forward speeds. Simultaneously the important stability derivatives were found for this instability and modifications were made subsequently in the suspension system to eliminate the instabilities in the longitudinal sense. Throughout this paper, all metric dimensions are given approximately.

Alternative edge illumination set-up for single-shot X-ray phase contrast imaging

2018 ◽  
Vol 124 (16) ◽  
pp. 164906 ◽  
Author(s):  
Cui Zhang ◽  
Xiaodong Pan ◽  
Hongjie Shang ◽  
Gongping Li
Keyword(s):  
Phase Contrast ◽  
Phase Contrast Imaging ◽  
Single Shot ◽  
Contrast Imaging ◽  
X Ray ◽  
Set Up

An Analysis of the Effects Causing an Asymmetric Behavior of the Lateral Lubricating Films of External Spur Gear Machines

2021 ◽  
Author(s):  
Kaeul Lim ◽  
Federico Zappaterra ◽  
Swarnava Mukherjee ◽  
Andrea Vacca
Keyword(s):  
Spur Gear ◽  
Common Assumption ◽  
Simulation Tools ◽  
Positive Displacement ◽  
Asymmetric Behavior ◽  
External Gear Pumps ◽  
Pressure Development ◽  
Gear Pumps ◽  
Set Up ◽  
Lateral Gaps

Abstract The torque efficiency and flow efficiency of positive displacement machines for fluid power applications are determined by the behavior of their internal lubricating interfaces. This aspect has motivated the development of tribological simulation tools for the analysis of these interfaces. The level of details these tools can provide allows explaining some counterintuitive aspects that occur in these interfaces. This paper focuses on a significant example, which is the high asymmetric behavior of the lubricating films occurring in pressure compensated external gear pumps. These units are often designed with a symmetric axial balancing compensation system. Notwithstanding, there are differences between the lateral gaps that can be explained only considering the mutual effects of the pressure development in the film and the material deformation. To study this problem, this paper utilizes the tool Multics-HYGESim developed by the authors’ research team. Two analyses are performed: the first one imposing axial symmetry in the behavior of the gap, which is the common assumption discussed in literature; the second one (referred to as “full configuration”), which holds the asymmetric behavior of the gap. An experimental set-up is used to validate the modeling assumptions based on the measurements of the drain leakage and volumetric efficiency. The main paper findings are on the uneven distribution of these leakages, which indicates an asymmetric behavior of the gap films in the unit.

Heat Treatment

2013 ◽  
pp. 271-324
Keyword(s):  
Heat Treatment ◽  
Surface Hardening ◽  
Precipitation Hardening ◽  
Temper Embrittlement ◽  
Induction Hardening ◽  
Heat Treatments ◽  
Metals And Alloys ◽  
Continuous Cooling Transformation Diagrams ◽  
Transformation Diagrams ◽  
Carbon System

Abstract This chapter discusses the processes used in manufacturing to thermally alter the properties of metals and alloys. It begins with a review of the iron-carbon system, the factors that affect hardenability, and the use of continuous cooling transformation diagrams. It then explains how various steels respond to heat treatments, such as annealing, normalizing, spheroidizing, tempering, and direct and interrupted quenching, and surface-hardening processes, such as flame and induction hardening, carburizing, nitriding, and carbonitriding. It also addresses the issue of temper embrittlement and discusses the effect of precipitation hardening on aluminum and other alloys.

Improving Mechanical Properties of Twin-Roll Cast AZ31 by Wire Rolling

2021 ◽  
Vol 1016 ◽  
pp. 957-963
Author(s):  
Marie Moses ◽  
Madlen Ullmann ◽  
Rudolf Kawalla ◽  
Ulrich Prahl
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Rolling Texture ◽  
Total Elongation ◽  
Roll Casting ◽  
Heat Treated ◽  
Heat Treated Condition ◽  
Set Up ◽  
Twin Roll Cast ◽  
Twin Roll

Since 2018, the institute of metal forming has been studying the novel twin-roll casting (TRC) of magnesium wire at the pilot research plant set up specifically for this purpose. Light microscopic and scanning electronic investigations were carried out within this work and show the unique microstructure of twin-roll cast AZ31 magnesium alloy with grain sizes of about 10 μm ± 4 μm in centre and 39 μm ± 26 μm near the surface of the sample. By means of a short heat treatment (460 °C/15 min), segregations can be dissolved and grain size changes in centre to 19 μm ± 12 μm (increase) and near the surface to 12 μm ± 7 μm (decrease). Further, the mechanical properties of the twin-roll cast and heat-treated wire were analysed by tensile testing at room temperature. By heat treatment, the total elongation could be increased by a third whereas the strength decreases slightly. In heat-treated state, no preferred orientation is evident. In addition to the twin-roll cast and the heat-treated condition, the rolled state was analysed. For this purpose, the twin-roll cast wire was hot rolled using an oval-square calibration. After hot rolling, a dynamic recrystallization and grain refinement of the twin-roll cast wire could be achieved. It can be seen, that an increase in strength as well as in total elongation occur after wire rolling. Beside this, a rolling texture is evident.

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