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DIFFRACTION OF FLEXURAL WAVES AND DYNAMIC STRESS CONCENTRATIONS IN ORTHOTROPIC PLATES WITH AN ARBITRARY CUTOUT
正交各向异性平板开孔弹性波的衍射与动应力集中

Ma Xingrui,Hu Chao,Wang Benli,Niu Yuqing,
马兴瑞
,胡超,王本利,牛玉清

力学学报 , 1997,
Abstract: In this paper, based on the governing equation for flexural waves of orthotropic plates, diffraction of elastic waves by cutouts and dynamic stress concentrations in the thin plate has been studied. An analytic method to solve dynamic stress concentrations in the plate with an arbitrary cutout is established. An asymptotic expansion solution that satisfies the boundary conditions on the edge of cutouts is obtained. Therefore the solution of the problem can be normalized by means of this method. Numerical results for dynamic moment factors of plates with circular and elliptic cutouts are presented.
Modified Reynolds Equation for Squeeze-Film Air Damping of Slotted Plates in MEMS Devices
Sun Yuancheng,Bao Minhang,Yang Heng,Huang Yiping,
Sun Yuancheng
,Bao Minhang,Yang Heng,Huang Yiping

半导体学报 , 2006,
Abstract: A differential equation for calculating squeeze-film air damping in slotted plates is developed by modifying the Reynolds equation.A term is added to account for the effect of airflow through the slots on the air damping of the plate.The end effect of the airflow in the slots is also treated by substituting an effective channel length for the geometric channel length (i.e.the thickness of the plate).The damping pressure distribution,damping force,and damping force coefficient of the slotted plates can be found by solving the equation under appropriate boundary conditions.With restrictions on the thickness and the lateral dimensions of the slotted plate removed,the equation provides a useful tool for analysing the squeeze-film air damping effect of slotted plates with finite thickness and finite lateral dimensions.For a typical slotted plate structure,the damping force coefficient obtained by this equation agrees well with that generated by ANSYS.
Optimum Design of Slotted Axial Flux Internal Stator Motor Using Genetic Algorithm for Electric Vehicle  [PDF]
S.Asghar Gholamian,M. Ardebili,K. Abbaszadeh,Seyyed Akbar Gholamian
International Journal of Software Engineering & Applications , 2011,
Abstract: Axial flux permanent magnet motors having a dual air-gap configuration have been designed andconstructed to achieve high power density and used in industries interestingly and specially in the system ofdriving electrical vehicles. In this paper, the equation related to the design and dimensions of double-sidedslotted axial flux synchronous motor with internal stator (TORUS) will be investigated. Then, an optimumdesign based on genetic algorithm with the purpose of increasing power density is presented. Twodimensionalfinite-element analysis (FEM) is used to demonstrate these optimization and its results will bepresented. Finally, it presents the resultant back emf waveform and current for a 1.0 kW, 48 V, 50 Hz, 4-poles/15-slots TORUS slotted axial motor prototype, based on our optimization techniques
Review on Stress and Vibration Analysis of Composite Plates
Avadesh K. Sharma,N.D. Mittal
Journal of Applied Sciences , 2010,
Abstract: A review on stress and vibration analysis of composite plates is presented in this study. The literature review is devoted on the free vibration and dynamic analysis, buckling analysis, failure analysis of composite laminated plates. Optimization is also considered in this review. The future research is summarized finally.
Casimir stress on parallel plates in de Sitter space  [PDF]
M. R. Setare,R. Mansouri
Physics , 2001, DOI: 10.1088/0264-9381/18/14/304
Abstract: The Casimir stress on two parallel plates in de Sitter background for massless scalar field satisfying Robin boundary conditions on the plates is calculated. The metric is written in conformally flat form to make maximum use of the Minkowski space calculations. Different cosmological constants are assumed for the space between and outside of the plates to have general results applicable to the case of domain wall formations in the early universe.
Stress intensity solutions for cracked orthotropic plates  [cached]
Sahli A.,Kebdani S.,Boutchicha D.,Rahmani O.
EPJ Web of Conferences , 2010, DOI: 10.1051/epjconf/20100609004
Abstract: In this paper, fracture mechanics in orthotropic plates, stress and displacement distributions around the crack tip in an anisotropic material are considered. Classical displacement based finite elements, elements with penalized equilibrium and elements with drilling degrees of freedom are employed. The path independent integrals J and I* are applied to orthotropic fracture mechanics problems to determine the stress intensity factor at the crack tip. Again, convergence studies are done, and the path independence of J and I* are investigated for orthotropic problems. Numerical results for typical fracture specimens are presented and discussed. The effect of the degree of anisotropy and fiber orientation on the stress intensity factor is also demonstrated.
Casimir stress on parallel plates in de Sitter space with signature change  [PDF]
M R Setare
Physics , 2006, DOI: 10.1142/S0217751X07035033
Abstract: The Casimir stress on two parallel plates in a de Sitter background corresponding to different metric signatures and cosmological constants is calculated for massless scalar fields satisfying Robin boundary conditions on the plates. Our calculation shows that for the parallel plates with false vacuum between and true vacuum outside, the total Casimir pressure leads to an attraction of the plates at very early universe.
Genetic Algorithm and Finite Element Analysis for Optimum Design of Slotted Torus Axial-Flux Permanent-Magnet Brushless DC Motor
Amin Mahmoudi;Nasrudin Abd Rahim;Hew Wooi Ping
PIER B , 2011, DOI: 10.2528/PIERB11070204
Abstract: This paper presents an inside-out axial-flux permanent-magnet brushless DC motor optimized by Finite Element Analysis (FEA) and Genetic Algorithm (GA) that uses sizing equation. The double-sided slotted-stator designed TORUS motor has sinusoidal back EMF waveform and maximum power density. The GA obtained the dimensions that gave the motor its highest power density. Field analysis of the dimensions was then put through FEA, to obtain and re-optimize the motor's characteristics. Possible design parameters were investigated via use of Commercial Vector Field Opera 14.0 software used in three-dimensional FEA simulation and of MATLAB 2010a in GA programming. Techniques such as modifying winding configuration and skewing the permanent magnets were explored to achieve the most-sinusoidal back-EMF waveform and minimized cogging torque. The desired technical specifications were matched by simulation results of the 3D FEA and the GA. The FEA and the GA simulation results comparison of the flux density in different parts of the designed motor at no-load condition agreed well.
Graphene nano ribbons subjected to axial stress  [PDF]
M. Neek-Amal,F. M. Peeters
Physics , 2011, DOI: 10.1103/PhysRevB.82.085432
Abstract: Atomistic simulations are used to study the bending of rectangular graphene nano ribbons subjected to axial stress both for free boundary and supported boundary conditions. The shape of the deformations of the buckled graphene nano ribbons, for small values of the stress, are sine waves where the number of nodal lines depend on the longitudinal size of the system and the applied boundary condition. The buckling strain for the supported boundary condition is found to be independent of the longitudinal size and estimated to be 0.86$%$. From a calculation of the free energy at finite temperature we find that the equilibrium projected two-dimensional area of the graphene nano ribbon is less than the area of a flat sheet. At the optimum length the boundary strain for the supported boundary condition is 0.48$%$.
Biomechanical Comparison of the Wedge Supported Plates at PTO
A. Yardimeden,M. H. Kelestemur,I. Esenkay
Archives of Materials Science and Engineering , 2007,
Abstract: Purpose: Proximal tibial osteotomy (PTO) is a widely used surgical procedure for the treatment in medial compartment osteoarthritis of the knee with mal-alignment, particularly in young and active patients. Several types of plates are developed recently at the medial opening wedge osteotomy technique. The main aim of this study is to make stress analysis and compare the stability of a commonly used anatomic “T” plate and 3 different wedge supported plates and their combinations which are designed by one of the author of this article.Design/methodology/approach: In this biomechanical study, calf tibial models were used in order to compare the stability of the plates under axial compression loading. 2 and 4 holes rectangular shape wedge supported plates, 4 holes reversed “L” shape wedge supported plates or combination of these and 6 holes anatomic “T” plates were used for the models. The compression behaviour of the model was tested by using a universal mechanical testing machine. And, a numerical method, ANSYS finite element code, was used for the stress analysis of the plates.Findings: The specimen fixed with the combination of 4 holes reversed “L” shapes and 2 holes rectangular shape plates and 6 holes anatomic “T” plates showed significantly better stability than those of others. The numerical and experimental results were well agreed.Practical implications: When Ti alloy plate is compared with stainless steel plate it is observed that the stress values do not change under applied loads and it does not show an advantage in term of stress. However, literature indicates that it has higher fatigue life and better electro-chemical properties.Originality/value: Biomechanical comparison of the wedge supported plates at proximal tibial osteotomy.
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