Tài liệu Cơ Khí - Chế Tạo Máy

A direct evidence of fatigue damage growth inside silicon mems structures obtained with ebic technique
In this study, EBIC technique was applied successfully to observe the growth of defects inside silicon MEMS structures. The changes of local contrast were successfully observed at the notch tip of the specimens, which remained the same through the hydrofluoric acid treatment after the experiment. The damage, which caused the local contrast change...
12 trang | Chia sẻ: huongthu9 | Ngày: 12/08/2021 | Lượt xem: 477 | Lượt tải: 0
An analytical approach to analyze nonlinear dynamic response of eccentrically stiffened functionally graded circular cylindrical shells subjected to time dependent axial compression and external pressure - Part 1: Governing equations establishment
A formulation of governing equations of eccentrically stiffened functionally graded circular cylindrical thin shells subjected to time dependent axial compression and external pressure based upon the classical shell theory and the smeared stiffeners technique with von Karman-Donnell nonlinear terms is proposed in this paper. An approximate three...
16 trang | Chia sẻ: huongthu9 | Ngày: 12/08/2021 | Lượt xem: 458 | Lượt tải: 0
An analytical approach to analyze nonlinear dynamic response of eccentrically stiffened functionally graded circular cylindrical shells subjected to time dependent axial compression and external pressure - Part 2: Numerical results and discussion
The nonlinear second-order differential three equations system (36-38) in Part 1 is solved by using the Runge-Kutta method and applying the Budiansky-Roth criterion to analyze the nonlinear dynamic response and critical dynamic buckling load. The frequencyamplitude relation of nonlinear vibration is also investigated. Some conclusions can be obtain...
13 trang | Chia sẻ: huongthu9 | Ngày: 12/08/2021 | Lượt xem: 465 | Lượt tải: 0
A coupling successive approximation method for solving duffing equation and its application
Findings of the paper are summarized as follows: 1. An algorithm to solve the Duffing equation is proposed, in which a method to transform the initial equation to the resulting equation and a coupling successive approximation method (CSAM) to solve the resulting equation are presented. 2. Based on the proposed algorithm, the analytic approximate...
19 trang | Chia sẻ: huongthu9 | Ngày: 12/08/2021 | Lượt xem: 510 | Lượt tải: 0
Transient analysis of laminated composite plates using nurbs-Based isogeometric analysis
composite plates is first studied. The displacement field is generally defined and is derived from CPT. The Newmark time-integration algorithm was chosen to approximate the ordinary differential equations in time. We have successfully extended an application of the NURBS-based isogeometric finite element approach to analyze dynamic response for ...
17 trang | Chia sẻ: huongthu9 | Ngày: 12/08/2021 | Lượt xem: 428 | Lượt tải: 0
Calculation of transonic flows around profiles with blunt and angled leading edges
In fact, transonic flows are used for large civil aircraft and other flight objects. The implementation of computational methods and deep understandings of physical nature of the transonic flow are always needed [6, 7]. The above analysis for subsonic-transonic flow and supersonic-transonic flow allows drawing the following conclusions. It is c...
13 trang | Chia sẻ: huongthu9 | Ngày: 12/08/2021 | Lượt xem: 469 | Lượt tải: 0
Nonlinear post-Buckling of thin fgm annular spherical shells under mechanical loads and resting on elastic foundations
Due to practical importance of FGM annular spherical shells and the lack of investigations on stability of these structures, the present paper aims to propose an analytical approach to study the problem of nonlinear buckling and postbuckling of FGM thin annular spherical shells on elastic foundations. Based on the classical thin shell theory, the ...
18 trang | Chia sẻ: huongthu9 | Ngày: 12/08/2021 | Lượt xem: 596 | Lượt tải: 0
A cell-Based smoothed discrete shear gap method (cs-fem-dsg3) for dynamic response of laminated composite plate subjected to blast loading
In this paper, the cell-based smoothed discrete shear gap method (CS-FEM-DSG3) is extended to investigate the dynamic response of laminated composite plate under the effect of blast loading modeled by some trigonometric time functions. Numerical results demonstrate that the proposed method can achieve accurate results by using only a relative co...
10 trang | Chia sẻ: huongthu9 | Ngày: 12/08/2021 | Lượt xem: 477 | Lượt tải: 0
On the convergence of a coupling successive approximation method for solving duffing equation
Findings of the paper are summarized as follows: 1. The convergence of the coupling successive approximation method (CSAM) is proved for Eq. (1) without using the assumption of small parameters. 2. Condition of convergence is obtained as follows where θ is denoted by (14). 3. The proposed algorithm is applied to some examples to verify the met...
18 trang | Chia sẻ: huongthu9 | Ngày: 11/08/2021 | Lượt xem: 500 | Lượt tải: 1
Dynamic response of three dimension tunnel on elastic foundation subjected to moving vehicle loads
This paper presented an algorithm of element finite method established for dynamic analysis of tunnel and foundation in space model subjected to moving loads of vehicle. Numerical investigation has been carried out for an example with different parameters and showed effects of parameters of structure and load to the dynamic response of tunnel-fou...
18 trang | Chia sẻ: huongthu9 | Ngày: 11/08/2021 | Lượt xem: 432 | Lượt tải: 0