• Title/Summary/Keyword: plates

Search Result 6,384, Processing Time 0.028 seconds

Surface treatment of bipolar plates for PEMFC (Proton Exchange Membrane Fuel Cell) application (PEMFC (Proton Exchange Membrane Fuel Cell)용 바이폴라 플레이트 표면개질)

  • Jeon, Gwang-Yeon;Yun, Young-Hoon;Cha, In-Su
    • Proceedings of the KIPE Conference
    • /
    • 2008.06a
    • /
    • pp.643-645
    • /
    • 2008
  • Stainless steel 304 and 316 plates were deposited with the multi-layered coatings of titanium film (0.1um) and gold film (1-2um) by an electron beam evaporation method. The XRD patterns of the stainless steel plates modified with the multi-layered coatings showed the crystalline phases of the external gold film and the stainless steel substrate. Surface microstructural morphologies of the stainless steel bipolar plates modified with multi-layered coatings were observed by AFM and FE-SEM images. The external gold films formed on the stainless steel plates showed microstructure of grains of about 100nm diameter. The grain size of the external surface of the stainless steel plates increased with the gold film thickness. The electrical resistance and water contact angle of the stainless steel bipolar plates covered with multi-layered coatings were examined with the thickness of the external gold film.

  • PDF

Shape Optimization in Laminated Composite Plates by Volume Control (최적 제어를 통한 복합적층판의 형상최적화)

  • 한석영;백춘호;박재용
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
    • /
    • 2003.10a
    • /
    • pp.277-282
    • /
    • 2003
  • The growth-strain method was applied to cutout optimization in laminated composite plates. Since the growth-strain method optimizes a shape by generating the bulk strain to make the distributed parameter uniform, the distributed parameter was chosen as Tsai-Hill value. In this study, of particular interest is to see whether the growth-strain method developed for shape optimization in isotropic media would work for laminated composite Plates. In volume control of the growth-strain method, it makes Tsai-Hill value at each element uniform in laminated composite plates under the predetermined volume. The shapes optimized by Tsai-Hill fracture index were compared with those of the initial shapes for the various load conditions and predetermined volumes of laminated composite plates. As a result, it was verified that volume control of the growth-strain method worked very well for cutout optimization in laminated composite plates.

  • PDF

Uplift response of circular plates as symmetrical anchor plates in loose sand

  • Niroumand, Hamed;Kassim, Khairul Anuar
    • Geomechanics and Engineering
    • /
    • v.6 no.4
    • /
    • pp.321-340
    • /
    • 2014
  • Uplift response of symmetrical circular anchor plates has been evaluated in physical model tests and numerical simulation using Plaxis. The behavior of circular anchor plates during uplift test was studied by experimental data and finite element analyses in loose sand. Validation of the analysis model was also carried out with 50 mm, 75 mm and 100 mm diameter of circular plates in loose sand. Agreement between the uplift responses from the physical model tests and finite element modeling using PLAXIS 2D, based on 100 mm computed maximum displacements was excellent for circular anchor plates. Numerical analysis using circular anchor plates was conducted based on hardening soil model (HSM). The research has showed that the finite element results gives higher than the experimental findings in the loose sand.

Benchmark Modal Stress-Resultant Distributions for Vibrating Rectangular Plates with Two Opposite Edges Free

  • Y. Xiang;Wang, C.M.;T. Utsunomiya;C. Machimdamrong
    • Computational Structural Engineering : An International Journal
    • /
    • v.1 no.1
    • /
    • pp.49-57
    • /
    • 2001
  • This paper presents exact solutions for the modal stress-resultant distributions for vibrating rectangular Mindlin plates involving two opposite sides simply supported while the other two sides free. These exact stress-resultants of vibrating plates with free edges, hitherto unavailable, are very important because they serve as benchmark solutions for checking numerical solutions and methods. Using the exact solutions of a square plate, this paper highlights the problem of determining accurate stress-resultants, especially the transverse shear forces and twisting moments in thin plates, when employing the widely used numerical methods such as the Ritz method and the finite element method. Thus, this study shows that there is a need for researchers to develop refinements to the Ritz method and the finite element method for determining very accurate stress-resultants in vibrating plates with free edges.

  • PDF

HYPERSENSITIZATION FOR ASTRONOMICAL PHOTOGRAPHIC PLATES: IIIa-J, IIIa-F, 103a-O, 103a-D and IIa-O PLATES (천체 사진 건판의 초증감 처리 : IIIa-J, IIIa-F, 103a-O, 103a-D 및 IIa-O 건판)

  • Jeon, Yeong-Beom;Sim, Gyeong-Jin
    • Publications of The Korean Astronomical Society
    • /
    • v.8 no.1
    • /
    • pp.119-136
    • /
    • 1993
  • Optimum hypering conditions are found for IIIa-J, IIIa-F, 103a-O, 103a-D, and IIa-O plates using hypersensitization machine in KAO. For every experimental plate we get speed gain, fog increment, signal to noise ratio and relative DQE according to hypering time and temperature. The hypersensitization method is baking with 8% hydrogen mixed gas. For IIIa-J, 103a-O, and 103a-D plates treated $65^{\circ}C$, 3 hours baking, the speed gains arc increased by about 10 times, 2 times, and 2 times compared to untreated plates, respectively. The fogs are increased by 0.08, 0.10, and 0.08, respectively. For IIIa-F, IIa-O plates treated $65^{\circ}C$, 2 hours baking, the speed gains are increased by about 4.7 times and 1.8 times compared to untreated plates, respectively. The fogs are increased by 0.15 and 0.04, respectively.

  • PDF

A Study on the refrigeration vehicle system installed eutectic solution plates for milk transportation (유제품 수송용 공융냉동판 적용 냉동차량 시스템 연구)

  • 윤상국
    • Journal of Advanced Marine Engineering and Technology
    • /
    • v.23 no.3
    • /
    • pp.338-345
    • /
    • 1999
  • The objective of this study is to developed the refrigeration vehicle system installed eutectic olu-tion plates which consists of copper tubes carrying the refrigerant between two aluminum plates and the space between the plates filled with eutectic solution. The numerical analysis for the loca-tion of plates to get the uniform low temperature distribution in storage space was carried out and the result showed that the top left-side and right-side walls were the proper places to install plates. For three different concentrations of ethylene glycol solution the temperature distribution of inside space were measured during the day time of summer and the 21% solution was found to be properto sustain the temperature of $5-10^{\circ}C$ for milk transportation. The result showed that the refrigeration truck installed eutectic plates was very efficient to keep the milk fresh during vehicle transportation.

  • PDF

Bending Analysis of Anisotropic Sandwich Plates with Multi-layered Laminated Composite faces (다적층 복합면재를 갖는 비등방성 샌드위치판의 휨해석)

  • Ji, Hyo-Seon
    • Journal of the Korean Society for Advanced Composite Structures
    • /
    • v.3 no.4
    • /
    • pp.17-26
    • /
    • 2012
  • This study presents a governing equations of bending behavior of anisotropic sandwich plates with multi-layered laminated composite faces. Based on zig-zag models for through thickness deformations, the shear deformation of composite faces is included. All edges of plate are assumed to be simply supported. Results of the bending analysis under lateral loads are presented for the influence of various lay up sequences of antisymmetric angle-ply laminated faces. The accuracy of the approach is ascertained by comparing solutions from the sandwich plates theory with composite faces to the laminated plates theory. Since the present analysis considers the bending stiffness of the core and also the transverse shear deformations of the laminated faces, the proposed method showed higher than that calculated according to the general laminated plates theory. The information presented might be useful to design sandwich plates structure with polymer matrix composite faces.

The Development of Inner Structure of Metallic Sandwich Plates for Bending (굽힘성형을 위한 금속 샌드위치판재의 내부구조재 개발)

  • Seong, D.Y.;Jung, C.G.;Yoon, S.J.;Shim, D.S.;Lee, S.H.;Ahn, D.G.;Yang, D.Y.
    • Transactions of Materials Processing
    • /
    • v.15 no.2 s.83
    • /
    • pp.126-131
    • /
    • 2006
  • Metallic sandwich plates are ultra-light materials not only with high strength and stiffness but also with other multifunctional physical properties. Inner dimpled shell structure can be fabricated by a piecewise sectional forming process, and then bonded with face sheets of the same material by resistance welding. Possible region for bending and limit radius of curvature are defined to compare the formability of sandwich plates. Tests have shown that sandwich plates with inner dimpled shell structure subject to bending have longer possible region for bending and smaller limit radius of curvature than other types of sandwich plates. The proposed inner dimpled shell structure is shown to have better formability of sandwich plates for bending than other types inner structures.

Analytical solution of nonlinear cylindrical bending for functionally graded plates

  • Daouadji, Tahar Hassaine;Hadji, Lazreg
    • Geomechanics and Engineering
    • /
    • v.9 no.5
    • /
    • pp.631-644
    • /
    • 2015
  • This article considers the problems of cylindrical bending of functionally graded plates in which material properties vary through the thickness. The variation of the material properties follows two power-law distributions in terms of the volume fractions of constituents. In addition, this paper considers orthotropic materials rather than isotropic materials. The traction-free condition on the top surface is replaced with the condition of uniform load applied on the top surface. Numerical results are presented to show the effect of the material distribution on the deflections and stresses. Results show that, all other parameters remaining the same, the studied quantities (stress, deflection) of P-FGM and E-FGM plates are always proportional to those of homogeneous isotropic plates. Therefore, one can predict the behaviour of P-FGM and E-FGM plates knowing that of similar homogeneous plates.

Square plates as symmetrical anchor plates under uplift test in loose sand

  • Niroumand, Hamed;Kassim, Khairul Anuar
    • Geomechanics and Engineering
    • /
    • v.6 no.6
    • /
    • pp.593-612
    • /
    • 2014
  • The uplift response of symmetrical square anchor plates has been evaluated in physical model tests and numerical simulations using Plaxis. The behavior of square anchor plates during uplift test was studied by experimental data and finite element analyses in loose sand. Validation of the analysis model was also carried out with 50 mm, 75 mm and 100 mm Length square plates in loose sand. Agreement between the uplift responses from the physical model tests and finite element modeling using PLAXIS 2D, based on 100 mm computed maximum displacements was excellent for square anchor plates. Numerical analysis using square anchor plates was conducted based on the hardening soil model (HSM). The research has shown that the finite element results are higher than the experimental findings in loose sand.