Strength of Surface Micromachined Diaphragms

1998 ◽  
Vol 518 ◽  
Author(s):  
Xing Yang ◽  
Frances M. Siu ◽  
Yu-Chong Tai
Keyword(s):  
Boundary Condition ◽  
Silicon Nitride ◽  
Boundary Conditions ◽  
Fabrication Process ◽  
Surface Micromachining ◽  
Fabrication Technique ◽  
Different Boundary Conditions ◽  
The Common

AbstractThis paper presents the study of the strength of surface micromachined diaphragms. It is found that the diaphragm strength strongly depends on the diaphragm boundary conditions. A new fabrication technique which does not change the mask and fabrication process is proposed to improve the common step-up boundary condition. Test diaphragms with diameters from 200 µm to 800 µm and three different boundary conditions have been fabricated using silicon nitride/PSG and silicon nitride/polysilicon surface micromachining processes. Experimentally, it is found that the strength of the diaphragms is significantly improved with the new boundary conditions. The application of this technique to other surface micromachined structures is also described.

scholarly journals Determining the Geometrical Sizes of Plates with Internal Hinges by Using Additional Conditions

2020 ◽  
Vol 2020 ◽  
pp. 1-15
Author(s):  
Vildan Yazıcı ◽  
Zahir Muradoğlu
Keyword(s):  
Finite Difference ◽  
Boundary Conditions ◽  
Difference Equations ◽  
Transmission Conditions ◽  
Elastic Plates ◽  
Different Boundary Conditions ◽  
Mechanical Constraints ◽  
Finite Difference Equations ◽  
The Common

For a system obtained by placing more than two elastic plates side by side, the transmission conditions are obtained at the common boundaries. Finite difference equations are developed for the problem of plates with internal hinges and applied for determination of the response of a system assembled from three different plates with different mechanical constraints between adjacent plates in this study. An algorithm is written to find out how long the size of the plates should be in order to obtain the desired amount of bending against the force affecting the system under different boundary conditions. The bisection and multigrid methods are used for this. These two methods are compared based on the obtained data.

scholarly journals Effects of Boundary Condition Models on the Seismic Responses of a Container Crane

2019 ◽  
Vol 9 (2) ◽  
pp. 241 ◽  
Author(s):  
Jungwon Huh ◽  
Van Nguyen ◽  
Quang Tran ◽  
Jin-Hee Ahn ◽  
Choonghyun Kang
Keyword(s):  
Boundary Condition ◽  
Boundary Conditions ◽  
Time History ◽  
Dynamic Responses ◽  
Seismic Excitation ◽  
Different Boundary Conditions ◽  
Container Crane ◽  
Condition Model ◽  
Boundary Condition Model ◽  
Significant Difference

In recent years, several large earthquakes have caused the collapse of container cranes, which have resulted in halting of freighting, and significantly affected the economy. Some reports are concerned the uplift and derailment events of crane legs, and the collapse of the crane itself. In this study, the effects of different boundary conditions used in the numerical method are investigated for a container crane under seismic excitation. Three different boundary conditions are considered in terms of the connection of the crane’s legs (wheels) and the ground (rails), namely pin support (PIN), gap element (GAP), and Friction contact (FC) elements, by using the SAP2000 program for a typical container crane. Then, time history dynamic analyses are conducted using nine recorded ground motions. Dynamic behaviors of the container crane are studied in terms of the total base shear, portal drift, and relative displacement of legs, by investigating the three types of base boundary conditions. The results of the study show that when the intensity of earthquakes is large enough to create uplift and derailment events, the selection of the boundary condition model considerably affects the dynamic responses of the container crane. In addition, when uplift and derailment of the crane occur, the FC support condition is the most compatible with the real behavior of the crane. On the other hand, under low seismic excitation, there is no significant difference of the crane behavior according to the choice of boundary condition model.

Evaluation of Buckling Performance of Fibre Metal Rectangular Plates: Experimental and Numerical Investigation

2014 ◽  
Vol 575 ◽  
pp. 185-190
Author(s):  
M. Vasumathi ◽  
Murali Vela
Keyword(s):  
Boundary Condition ◽  
Boundary Conditions ◽  
Buckling Load ◽  
Thin Layers ◽  
Maximum Deviation ◽  
Critical Buckling Load ◽  
Buckling Strength ◽  
Different Boundary Conditions ◽  
Simply Supported ◽  
Fibre Metal

Carbon reinforced aluminium laminate (CARAL) is a fibre metal laminate which consists of layers of carbon fibre and thin layers of aluminium. Buckling strength of CARAL under various support conditions is studied in this paper. Since CARAL is composed of fibre and metal, the pattern of failure of the laminate under compressive loads is truly imperative. The compressive buckling strength depends on geometrical parameters like length and width of the specimen and the sequence in which the layers are stacked. It also depends on the boundary condition. In this study, the critical buckling load is determined by varying the parameters such as aspect ratio (length/width), stacking sequence and boundary condition. Two different boundary conditions are considered, simply supported and fixed support condition. Numerical simulation analysis shows a maximum deviation of 16.72% from experimental results. The different failure modes executed by the laminate under compressive loading are also determined. The critical buckling load of CARAL constrained on all sides is evaluated numerically for different boundary conditions. Buckling load, in this case, takes maximum value when CARAL is clamped on all sides whereas it takes minimum value when the plate is simply supported on three sides keeping the fourth side fixed.

scholarly journals Neumann and Robin type boundary conditions in Fractional Orlicz-Sobolev spaces

2020 ◽  
Author(s):  
Sabri Bahrouni ◽  
Ariel Salort
Keyword(s):  
Boundary Condition ◽  
Boundary Conditions ◽  
Sobolev Spaces ◽  
Weak Solutions ◽  
Nonlocal Problem ◽  
Nonlocal Problems ◽  
Different Boundary Conditions ◽  
Nonstandard Growth ◽  
Type Boundary ◽  
Type Boundary Condition

In the first part of this article we deal with the existence of at least three non-trivial weak solutions of a nonlocal problem with nonstandard growth involving a nonlocal Robin type boundary condition. The second part of the article is devoted to study eigenvalues and minimizers of  several nonlocal problems for the fractional $g-$Laplacian $(-\Delta_g)^s$ with different boundary conditions, namely, Dirichlet, Neumann and Robin.

DYNAMICAL EVOLUTION OF ROTATING ACCRETION USING DIFFERENT BOUNDARY CONDITIONS: STATE AFTER STABLE ACCRETION DISK CREATED

2007 ◽  
Vol 16 (10) ◽  
pp. 1541-1553
Author(s):  
ORHAN DÖNMEZ
Keyword(s):  
Boundary Condition ◽  
Black Hole ◽  
Shock Waves ◽  
Boundary Conditions ◽  
Accretion Disk ◽  
Binary Systems ◽  
Schwarzschild Black Hole ◽  
Different Boundary Conditions ◽  
Outflow Boundary ◽  
Armed Spiral

The 2D time-dependent solution of the thin and stable accretion disk with two-armed spiral shock waves in a closed binary system have been presented on the equatorial plane around the Schwarzschild black hole in Donmez (2004).2 The subject of this paper is to study the influence of two different boundary conditions, far away from a black hole called the outer boundary, on an accretion disk around the black hole during the time evolution. We have started with a stable accretion disk after the point where two-armed spiral shock waves were created (Donmez, 2004).2 The initial data which is also called the freezing boundary is used as a first boundary condition. As a second one, we use the outflow boundary condition. In both cases, the accretion disk is created and gases on the disk made closed trajectories. As a stable tori close to the black hole is created by using the first boundary, freezing condition, which has a ~10M radius where M is the mass of black hole, and the other boundary, outflow, creates stable two-armed spiral shock waves. The last stable circular orbit around the Schwarzschild black hole for this type of accretion disk is located around 11M in the case of the freezing boundary condition. The results of these simulations show that the tori and spiral shock waves are created in each case using freezing and the outflow boundary, respectively, and it also suggests that spiral waves are a robust feature of accretion disks in binary systems, and that these spiral shocks can indeed transfer the gravitational energy to the radiation energy observed by different X-ray satellites.

scholarly journals On the Non-invariance of Distributions of Reaction Matrix Parameters Under Changes in Boundary Conditions

1972 ◽  
Vol 25 (4) ◽  
pp. 349
Author(s):  
WK Bertram ◽  
JL Cook
Keyword(s):  
Boundary Condition ◽  
Boundary Conditions ◽  
Statistical Distributions ◽  
Current Opinion ◽  
Different Boundary Conditions ◽  
Reaction Matrix

Contrary to current opinion, the statistical distributions of level spacings and reduced widths when applied to the reaction matrix are not invariant under changes in the boundary condition matrix or the matching radius. General arguments are given, together with specific examples which violate the invariance requirements. We conclude that it may be the parameters of the collision matrix which should be analysed and considered as the invariant parameters. It is shown that if, for a specific set of boundary conditions, the distributions of level spacings and reduced widths are uncorrelated, then correlations between the level spacings and widths must exist when different boundary conditions are used.

Temperature-Graded Ferroelectric Thin Films under Two Boundary Conditions

2013 ◽  
Vol 750-752 ◽  
pp. 1910-1913
Author(s):  
Hui Chen ◽  
Xin Yue Bi ◽  
Li Jia Zhang ◽  
Yan Shen
Keyword(s):  
Boundary Condition ◽  
Temperature Gradient ◽  
Boundary Conditions ◽  
Mean Field ◽  
Field Approximation ◽  
Mean Field Approximation ◽  
Ferroelectric Films ◽  
Film Properties ◽  
Different Boundary Conditions ◽  
The Mean

In the framework of the mean field approximation, a transverse Ising model (TIM) was adopted to analyze the polarization properties of temperature-graded ferroelectric films under two boundary conditions, free boundary condition (FBC) and clamped boundary condition (CBC). Due to the ferroelectric distortion aroused by temperature gradient across the film, the elastic thermal stress increased. A distribution function was introduced to characterize the different boundary conditions. The results show that boundary conditions have very important influence on film properties. Polarizations under FBC are larger than that under CBC, polarization variations aroused by changed film thickness and temperature gradient under FBC are not as obvious as that under CBC, and films under different boundary conditions present obviously different physical behavior.

Numerical Simulation Technique of Disks Skipping Based on the SPH Method

2014 ◽  
Vol 668-669 ◽  
pp. 494-498
Author(s):  
Yong Hu Wang ◽  
Cai Hua Chen ◽  
Ting Yu Zhao ◽  
Wei Hu
Keyword(s):  
Numerical Simulation ◽  
Boundary Condition ◽  
Boundary Conditions ◽  
Simulation Technique ◽  
Contrastive Analysis ◽  
Sph Method ◽  
Different Boundary Conditions ◽  
The Future ◽  
Numerical Simulation Technique

It is significant for the phenomena of bouncing on water to analyze the ditching procedure of any kind of aircraft. The SPH method is employed to achieve a numerical simulation in the architecture of LS-DYNA and PrePost programs. The water domain is modeled by SPH and the boundary condition is discussed too. Through a set of contrastive analysis of different boundary conditions, some constructive suggestions of establishing the boundary conditions are given to deeply simulate aircraft ditching in the future.

Sturm-Liouville Problem for Stationary Differential Operator with Nonlocal Two-Point Boundary Conditions

2006 ◽  
Vol 11 (1) ◽  
pp. 47-78 ◽  
Author(s):  
S. Pečiulytė ◽  
A. Štikonas
Keyword(s):  
Boundary Condition ◽  
Differential Operator ◽  
Boundary Conditions ◽  
Nonlocal Boundary Condition ◽  
Nonlocal Boundary ◽  
Liouville Problem ◽  
Complex Case ◽  
Qualitative Behavior ◽  
Point Boundary ◽  
Sturm Liouville

The Sturm-Liouville problem with various types of two-point boundary conditions is considered in this paper. In the first part of the paper, we investigate the Sturm-Liouville problem in three cases of nonlocal two-point boundary conditions. We prove general properties of the eigenfunctions and eigenvalues for such a problem in the complex case. In the second part, we investigate the case of real eigenvalues. It is analyzed how the spectrum of these problems depends on the boundary condition parameters. Qualitative behavior of all eigenvalues subject to the nonlocal boundary condition parameters is described.

Sign in / Sign up

Export Citation Format

Share Document