Local Tribological Characteristics of Steel Sheets for Microforming

The die radius represents the important local part of drawing die due to transferring contact loading under deep drawing. Within the experiments local contact pressure on die radius was researched using numerical simulation of strip drawn test and micro deep-drawing. Experimental research of strip drawn test was done using coatings with different alloying – under alloyed, optimal and slightly pre alloyed. Alloying level was evaluated by phase composition and % Fe in coating. Presented coatings were created on IF steel sheet DX54D. Experimental results of strip drawn test were used to verify strip-drawn test numerical simulation. Based on numerical simulation results, contact pressure on drawing die radius at deep drawing of cups Ø 50 mm and Ø 15 mm were observed.

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Numerical Simulation on Thixo-Forging of Magnesium Matrix Composite

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.189-193.2535 ◽

2011 ◽

Vol 189-193 ◽

pp. 2535-2538 ◽

Cited By ~ 1

Author(s):

Hong Yan ◽

Wen Xian Huang

Keyword(s):

Numerical Simulation ◽

Matrix Composite ◽

Metal Flow ◽

Magnesium Matrix Composite ◽

Magnesium Matrix ◽

Simulation Based ◽

Prior Literature ◽

Simulation Results ◽

Computer Numerical Simulation ◽

Good Agreement

The thixo-forging of magnesium matrix composite was analyzed with computer numerical simulation based on rigid viscoplastic finite element method. The constitutive model of SiCp/AZ61 composite was established in our prior literature. Behavior of metal flow and temperature field were obtained. The differences between traditional forging and thixo-forging processes were analyzed. Results indicated that thixo-forging was better in filling cavity than forging. Simulation results were good agreement with experimental ones.

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Study on flow field of gas–solid two-phase pulsed jet

International Journal of Modern Physics B ◽

10.1142/s0217979219502795 ◽

2019 ◽

Vol 33 (24) ◽

pp. 1950279

Author(s):

Xinhua Song ◽

Xiaojie Li ◽

Yang Wang ◽

Honghao Yan

Keyword(s):

Numerical Simulation ◽

Flow Field ◽

Particle Distribution ◽

Starch Granule ◽

Injection Pressure ◽

Two Phase ◽

Particle Injection ◽

Pulsed Jet ◽

Simulation Based ◽

Simulation Results

In this paper, a computational fluid dynamics–discrete element method (CFD–DEM) coupling method is established to simulate the starch granule injection by coupling CFD and DEM. Then a gas–solid two-phase pulsed jet system is designed to capture the flow field trajectory of particle injection (colored starch with a mean diameter of 10.67 [Formula: see text]m), and the image is processed by color moment and histogram. Finally, the simulation results are compared with the experimental results, and the following conclusions are drawn. The numerical simulation results show that with the increase of injection pressure, the injection height increases gradually. When the injection pressure reaches above 0.4 MPa, the increase of injection height decreases. The experimental images show that the larger the pressure (i.e., the greater the initial velocity), the faster the velocity of particle distribution in the space, and the injection heights with the injection pressures of 0.4 MPa and 0.5 MPa are close, which is consistent with the result from the FLUENT numerical simulation based on CFD–DEM.

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Temperature distribution simulations during electron beam freeform fabrication process based on the fully threaded tree

Rapid Prototyping Journal ◽

10.1108/rpj-12-2016-0211 ◽

2019 ◽

Vol 25 (6) ◽

pp. 989-997

Author(s):

Yajun Yin ◽

Wei Duan ◽

Kai Wu ◽

Yangdong Li ◽

Jianxin Zhou ◽

...

Keyword(s):

Numerical Simulation ◽

Temperature Field ◽

Electron Beam ◽

Additive Manufacturing ◽

Temperature Distribution ◽

Design Methodology ◽

Content Type ◽

Freeform Fabrication ◽

Simulation Based ◽

Simulation Results

Purpose The purpose of this study is to simulate the temperature distribution during an electron beam freeform fabrication (EBF3) process based on a fully threaded tree (FTT) technique in various scales and to analyze the temperature variation with time in different regions of the part. Design/methodology/approach This study presented a revised model for the temperature simulation in the EBF3 process. The FTT technique was then adopted as an adaptive grid strategy in the simulation. Based on the simulation results, an analysis regarding the temperature distribution of a circular deposit and substrate was performed. Findings The FTT technique was successfully adopted in the simulation of the temperature field during the EBF3 process. The temperature bands and oscillating temperature curves appeared in the deposit and substrate. Originality/value The FTT technique was introduced into the numerical simulation of an additive manufacturing process. The efficiency of the process was improved, and the FTT technique was convenient for the 3D simulations and multi-pass deposits.

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Efficiency Metallic Leading Edge Structure Bird Strike Resistant Design

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.338.84 ◽

2011 ◽

Vol 338 ◽

pp. 84-89 ◽

Cited By ~ 1

Author(s):

Mei Ying Zhao ◽

Jing Jing Li

Keyword(s):

Numerical Simulation ◽

Absorption Rate ◽

Leading Edge ◽

Experimental Results ◽

Structural Quality ◽

Bird Strike ◽

Edge Structure ◽

Simulation Based ◽

Simulation Results ◽

Resistant Structure

This article investigated a new metallic leading edge bird strike resistant structure, using corrugate board as its enhanced component to absorb more bird kinetic energy. This structure was called as Corrugate Board Leading Edge (CBLE) structure. To verify the structure’s bird strike resistant ability, numerical simulation based on the LS-DYNA was carried out, and succeeding experiments were performed. However, the experimental results were not exciting. They were not as the simulation results we expected. The reasons were analyzed through this article. Finally a rivet-relative model was created considering the influence of riveting. This model was proved to be accurate by comparing with experimental results. Based on the analysis above, an Optimized CBLE (O-CBLE) structure was used to optimize the bird strike resistant ability, the energy absorption rate of O-CBLE structure increased 11.4% while the structural quality was only slightly increased.

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Influence of Tool Geometry Variation on the Punch Force in Micro Deep Drawing

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.554-557.1306 ◽

2013 ◽

Vol 554-557 ◽

pp. 1306-1311 ◽

Cited By ~ 5

Author(s):

Gerrit Behrens ◽

Frank Vollertsen

Keyword(s):

Deep Drawing ◽

Tool Geometry ◽

Process Stability ◽

Micro Forming ◽

Punch Force ◽

Tool Geometries ◽

Drawing Die ◽

Micro Deep Drawing ◽

Nominal Size ◽

The Impact

Micro forming processes are very well suited for manufacturing of small metal parts in large quantities and micro deep drawing provides a great application potential for the manufacturing of parts with complex shapes. But size effects like changed tribology and material properties usually result in smaller process windows for micro forming operations. Process caused wear as well as large inaccuracy in manufacturing of micro forming tools is responsible for geometrical deviation of the tools from nominal size. Both influences can have essential impact on the process window size and process stability. A better understanding of the influence of tool geometry on process stability can help to improve and optimize process control in micro forming. In addition, a quantitative judgment of the impact of wear and manufacturing inaccuracy will be possible. Therefore, in this study, the impact of different tool geometries on the punch force in micro deep drawing was investigated. Significantly varied tool geometries were punch diameter, drawing gap, punch and drawing die radius and shape of the die edge. FEM simulations as well as experiments were used to determine tool geometry influence on the punch force of a micro deep drawing process. Hereby, it was possible to classify each geometry variation regarding its impact on the punch force and therefore on one important parameter of the process stability. Results show that the greatest impact on the punch force was caused by modifications of the punch diameter and variation of the drawing gap. Changes in punch or drawing die radii proved to be of minor importance.

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Investigation of Indoor Environment for a Data Center

Volume 9: Heat Transfer, Fluid Flows, and Thermal Systems, Parts A, B and C ◽

10.1115/imece2009-12513 ◽

2009 ◽

Author(s):

Lingcang Li ◽

Yanlei Liu ◽

Xiuling Wang ◽

A. G. Agwu Nnanna

Keyword(s):

Experimental Data ◽

Numerical Simulation ◽

Relative Humidity ◽

Indoor Air ◽

Data Center ◽

Indoor Environment ◽

Low Cost ◽

Simulation Based ◽

Simulation Results ◽

Volume Method

Special indoor air environment requirements are needed for the data center, such as ambient temperature, airflow pattern, relative humidity and ozone concentration to maintain the reliability of a computer system. In this paper, a numerical simulation based on 3-D Finite Volume Method has been conducted for a data center at Purdue University Calumet. The purpose of the simulation is to find out the most effective and low-cost air condition system. Results for temperature, relative humidity distributions as well as velocity patterns are presented. Mesh independent studies are performed. Numerical results are validated by experimental data. Suggestions are given based on the simulation results for improving the indoor environment of the data center.

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Reverse Deep Drawing: Experimental and Numerical Simulation Results

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.230-232.541 ◽

2002 ◽

Vol 230-232 ◽

pp. 541-544 ◽

Cited By ~ 1

Author(s):

P.Y. Manach ◽

Marta C. Oliveira ◽

S. Thuillier ◽

Luís Filipe Menezes

Keyword(s):

Numerical Simulation ◽

Deep Drawing ◽

Simulation Results ◽

Reverse Deep Drawing

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The Resistance of Ship Web Girders in Collision and Grounding

Mathematical Problems in Engineering ◽

10.1155/2014/720542 ◽

2014 ◽

Vol 2014 ◽

pp. 1-13 ◽

Cited By ~ 4

Author(s):

Zhenguo Gao ◽

Song Yang ◽

Zhiqiang Hu

Keyword(s):

Numerical Simulation ◽

Analytical Method ◽

Previous Experiment ◽

Deformation Model ◽

Deformation Characteristics ◽

Concentrated Load ◽

Reliable Assessment ◽

Comparison Results ◽

Simulation Based ◽

Simulation Results

Ship web girders play an important role in ship structure performance during collision and grounding accidents. The behavior of web girders subjected to in-plane concentrated load is investigated by numerical simulation and theoretical analysis in this paper. A numerical simulation based on previous experiment is conducted to give insight to the deformation mechanism of crushing web girders. Some new important deformation characteristics are observed through the simulation results. A new theoretical deformation model is proposed featured with these deformation characteristics, and a simplified analytical method for predicting the instantaneous and mean resistances of crushing web girders is proposed. The proposed method is verified by two previous experiments and a series of numerical simulations. The agreement between the solutions by the proposed method and the experiment results is good. The comparison results between the proposed analytical method and numerical simulation results are satisfactory for most cases. The proposed analytical method will contribute to the establishment of an efficient method for fast and reliable assessment of the outcome of ship accidental collisions and grounding events.

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Investigation of Multi-layered Fire Doors with Gypsum Layer Exposed to Fire

Periodica Polytechnica Civil Engineering ◽

10.3311/ppci.15676 ◽

2021 ◽

Author(s):

Remigijus Guobys ◽

Vadim Mokshin

Keyword(s):

Numerical Simulation ◽

Fire Test ◽

Convective Heat Transfer Coefficient ◽

Layered Structures ◽

Gypsum Board ◽

Temperature Changes ◽

Steel Sheets ◽

Simulation Results ◽

Dehydration Effect ◽

Good Agreement

This article analyzes gypsum board dehydration effect on heat conductivity and deformation of multi-layered mechanical structures subjected to temperature changes. Specially designed structures (fire doors) consisting of steel sheets with stone wool and gypsum insulating layers in between were heated in furnace for a specified period of time of not less than 60 min. Temperature versus time curves and deformations of multi-layered structures were obtained. Experimental results were verified by numerical simulation. Experimental data was found to be in good agreement with numerical simulation results. The percent differences between door temperatures from simulation and fire test don’t exceed 9 %. This shows that thermal behavior of such multi-layered structures can be investigated numerically avoiding time-consuming and expensive fire tests. The data obtained allowed to calculate convective heat transfer coefficient of gypsum board, which was fitted into multi-layered mechanical structure. It was found that it is more advantageous to place gypsum layer in the middle of the structure rather than closer to the fire source in order to cool the structure more efficiently during fire.

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