共查询到20条相似文献,搜索用时 31 毫秒
1.
Simulation and application of three-dimensional migration-accumulation of oil resources 总被引:1,自引:0,他引:1
IntroductionTheoilformationinsedimentbasins,itsdisplacement,transportandaccumulation,andthefinalformationofoildepositshavebeenthekeyproblemsintheexplorationofoil_gasresources.Howhasoilbeenaccumulatedinthepresentloopaccordingtothemechanicsofimmiscible… 相似文献
2.
A theoretical method for analyzing the axisymmetric plane strain elastodynamic problem of a non-homogeneous orthotropic hollow
cylinder is developed. Firstly, a new dependent variable is introduced to rewrite the governing equation, the boundary conditions
and the initial conditions. Secondly, a special function is introduced to transform the inhomogeneous boundary conditions
to homogeneous ones. By virtue of the orthogonal expansion technique, the equation with respect to the time variable is derived,
of which the solution can be obtained. The displacement solution is finally obtained, which can be degenerated in a rather
straightforward way into the solution for a homogeneous orthotropic hollow cylinder and isotropic solid cylinder as well as
that for a non-homogeneous isotropic hollow cylinder. Using the present method, integral transform can be avoided and it can
be used for hollow cylinders with arbitrary thickness and subjected to arbitrary dynamic loads. Numerical results are presented
for a non-homogeneous orthotropic hollow cylinder subjected to dynamic internal pressure.
The project supported by the National Natural Science Foundation of China (10172075 and 10002016) 相似文献
3.
对四种不同结构中心刚体-柔性Euler Bernoulli梁系统进行刚柔耦合动力学分析.其中以等截面梁、变截面梁、等截面回形梁、变截面回形梁为对象,研究楔形梁及回形梁对系统的末端变形位移影响.变截面梁的宽高尺寸沿着轴向线性变化.梁的变形包含了轴向、横向、耦合变形项(横向弯曲引起的纵向缩短).采用假设模态法和第二类Lagrange方程建立系统的动力学方程,并用C++编写软件进行动力学仿真.研究表明:在相同条件下,梁的截面尺寸及空心部分对梁末端变形位移影响十分明显,且当梁在较大变形情况下,该高次耦合模型依然能得到正确的结果,因此在针对实际结构建模时,建立符合实际截面的模型至关重要. 相似文献
4.
The stress problem for corrugated hollow transversely isotropic cylinders is solved in three-dimensional formulation for certain end conditions. Discrete Fourier series are used to make the problem one-dimensional, which is then solved by the stable discrete-orthogonalization method. Examples of analysis are given__________Translated from Prikladnaya Mekhanika, Vol. 41, No. 3, pp. 62–69, March 2005. 相似文献
5.
Jiaxi Zhou Zichen Deng Xiuhui Hou 《Acta Mechanica Solida Sinica》2010,23(2):156-166
The transient thermal response of a thick orthotropic hollow cylinder with finite length is studied by a high order shell theory. The radial and axial displacements are assumed to have quadratic and cubic variations through the thickness, respectively. It is important that the radial stress is approximated by a cubic expansion satisfying the boundary conditions at the inner and outer surfaces, and the corresponding strain should be least-squares compatible with the strain derived from the strain-displacement relation. The equations of motion are derived from the integration of the equilibrium equations of stresses, which are solved by precise integration method (PIM). Numerical results are.obtained, and compared with FE simulations and dynamic thermo-elasticity solutions, which indicates that the high order shell theory is capable of predicting the transient thermal response of an orthotropic (or isotropic) thick hollow cylinder efficiently, and for the detonation tube of actual pulse detonation engines (PDE) heated continuously, the thermal stresses will become too large to be neglected, which are not like those in the one time experiments with very short time. 相似文献
6.
For the thermoelastic dynamic axisymmetric problem of a finite orthotropic hollow cylinder, one comes closer to reality to
involve the effect of axial strain than to consider the plane strain case only. However, additional mathematical difficulties
should be encountered and a different solution procedure should be developed. By the separation of variables, the thermoelastic
axisymmetric dynamic problem of an orthotropic hollow cylinder taking account of the axial strain is transformed to a Volterra
integral equation of the second kind for a function of time, which can be solved efficiently and quickly by the interpolation
method. The solutions of displacements and stresses are obtained. It is noted that the present method is suitable for an orthotropic
hollow cylinder with an arbitrary thickness subjected to arbitrary axisymmetric thermal loads. Numerical comparison is made
to show the effect of the axial strain on the displacements and stresses.
The project supported by the National Natural Science Foundation of China (10172075) and China Postdoctoral Science Foundation
(20040350712) 相似文献
7.
The three-dimensional theory of elasticity is used to study the free vibrations of an anisotropic hollow cylinder with different
boundary conditions at the ends. The relevant problem is solved by a numerical-and-analytic method. Spline approximation and
collocation is used to reduce the partial differential equations of elasticity to a boundary-value problem for a system of
ordinary differential equations of high order for the radial coordinate, which is solved using the stable discrete-orthogonalization
and incremental-search methods. The calculated results for an orthotropic inhomogeneous cylinder with boundary conditions
of several types are presented
Translated from Prikladnaya Mekhanika, Vol. 44, No. 10, pp. 74–85, October 2008. 相似文献
8.
Parallel arithmetic numerical simulation and application of secondary migration-accumulation of oil resources 总被引:1,自引:1,他引:0
From such actual conditions as the effects of characteristics of miltilayer petroleum geology and permeation fluid mechanics, a new numerical model is put forward and coupling splitting-up implicit interactive scheme is formed. For the actual situation of Dongying hollow ( four-layer ) and Tanhai region ( three-layer ) of Shengli Petroleum Field, the numerical simulation test results and the actual conditions are coincident. 相似文献
9.
L. O. Grigor’eva 《International Applied Mechanics》2006,42(12):1371-1379
The paper proposes and analyzes different approaches to constructing numerical schemes to solve the nonstationary vibration
problem for a radially polarized piezoelectric hollow cylinder with different electric boundary conditions under mechanical
loading. It is established that when the cylinder is subjected to internal pressure, the radial displacements are similar
and the longitudinal displacements substantially different in cylinders with electroded and nonelectroded surfaces
__________
Translated from Prikladnaya Mekhanika, Vol. 42, No. 12, pp. 67–75, December, 2006. 相似文献
10.
层合球面各向同性热释电空心球的瞬态响应 总被引:1,自引:0,他引:1
运用叠加原理,将层合球面各向同性热释电空心球的球对称动力学问题的解分成准静态和动
态两部分,准静态部分首先运用状态空间法给出了显式表达式,然后运用分离变量法、初参
数法和特征函数展开技术,给出了动态部分的表示式,再结合内外表面上的电学边界条件和
界面上的电学连续条件,导出一个关于时间函数的第二类Volterra积分方程,运用插值法
可成功地给出此积分方程的高精度数值解,最终可求得原问题的位移、应力、电位移以及电
势的响应. 此方法适用任意层数且各层是任意厚度的层合热释电空心球作用随时间以任意形
式变化的球对称温度场. 文中还给出了数值结果. 相似文献
11.
基于轴对称平面应变问题的运动方程及弹性梯度材料的应力和位移关系,通过将圆筒分层使材料性质离散为分段常数函数,同时在时域内应用有限差分格式,求得了材料性质沿径向梯度变化的圆筒弹性动力学解。本文解不仅适合任意梯度的弹性圆筒,而且容易满足多种形式的初始条件和边界条件。通过对材料性质沿径向为连续函数分布和分段函数分布的梯度圆筒数值分析,并与已有文献结果比较,得出本文解与已有文献的解吻合较好,验证了本文解的正确性和有效性。对材料性质为分段函数的三层组合圆筒分析发现,中间功能梯度层的指数分布因子对圆筒的径向位移和应力随时间变化都会产生显著影响。 相似文献
12.
13.
The piezoelectric phenomenon has been exploited in science and engineering for decades. Recent advances in smart structures
technology have lead to a resurgence of interest in piezoelectricity, and in particular, in the solution of fundamental boundary-value
problems. In this paper, we develop an analytic solution to the axisymmetric problem of an infinitely long, radially polarized,
radially orthotropic piezoelectric hollow circular cylinder. The cylinder is subjected to uniform internal pressure, or a
constant potential difference between its inner and outer surfaces, or both. An analytic solution to the governing equilibrium
equations (a coupled system of second-order ordinary differential equations) is obtained. On application of the boundary conditions,
the problem is reduced to solving a system of linear algebraic equations. The stress distributions in the cylinder are obtained
numerically for two typical piezoceramics of technological interest, namely PZT-4 and BaTiO3. It is shown that the hoop stresses in a cylinder composed of these materials can be made virtually uniform throughout the
cross-section by applying an appropriate set of boundary conditions.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
14.
15.
爆轰载荷作用下球形空腔的动力响应 总被引:7,自引:1,他引:7
以位移为未知量,利用拉普拉斯变换法,研究了球形空腔在爆轰载荷作用下的动力响应问题,获得了问题的参数解,并通过直接代入,验证了解的正确性。 相似文献
16.
An elastodynamic solution for plane-strain response of functionally graded thick hollow cylinders subjected to uniformly-distributed
dynamic pressures at boundary surfaces is presented. The material properties, except Poisson’s ratio, are assumed to vary
through the thickness according to a power law function. To achieve an exact solution, the dynamic radial displacement is
divided into two quasi-static and dynamic parts, and for each part, an analytical solution is derived. The quasi-static solution
is obtained by means of Euler’s equation, and the dynamic solution is derived using the method of the separation of variables
and the orthogonal expansion technique. The radial displacement and stress distributions are plotted for various functionally
graded material (FGM) hollow cylinders under different dynamic loads, and the advantages of the presented method are discussed.
The proposed analytical solution is suitable for analyzing various arrangements of hollow FGM cylinders with arbitrary thickness
and arbitrary initial conditions, which are subjected to arbitrary forms of dynamic pressures distributed uniformly on their
boundary surfaces. 相似文献
17.
An elastodynamic solution for plane-strain response of functionally graded thick hollow cylinders subjected to uniformly-distributed dynamic pressures at boundary surfaces is presented. The material properties, except Poisson’s ratio, are assumed to vary through the thickness according to a power law function. To achieve an exact solution, the dynamic radial displacement is divided into two quasi-static and dynamic parts, and for each part, an analytical solution is derived. The quasi-static solution is obtained by means of Euler’s equation, and the dynamic solution is derived using the method of the separation of variables and the orthogonal expansion technique. The radial displacement and stress distributions are plotted for various functionally graded material (FGM) hollow cylinders under different dynamic loads, and the advantages of the presented method are discussed. The proposed analytical solution is suitable for analyzing various arrangements of hollow FGM cylinders with arbitrary thickness and arbitrary initial conditions, which are subjected to arbitrary forms of dynamic pressures distributed uniformly on their boundary surfaces. 相似文献
18.
光镊技术中,会聚的空心光束形成的能量光阱可用来捕获吸光性颗粒或操纵吸光性颗粒沿光轴方向运动。采用Gerchberg-Saxton(GS)算法计算所需相位,并将相位载入相位型空间光调制器来获得空心光束。为了提高会聚的空心光束能量,对空间光调制器相位屏进行预处理,叠加数字闪耀光栅位相,实现了将四个一级衍射谱闪耀至零级干涉极大位置,空心光束能量提高到原来的4.7倍。为了消除空间光调制器二维光栅结构所形成的零级谱亮斑以及高级谱的影响,在相位屏上加入球面波相位,使得空心光束衍射谱平面与零级谱平面的空间位置分离,并采用带通滤波器将空间光调制器的零级谱亮斑和高级谱滤掉。采用高度会聚透镜将所得空心光束会聚为微米尺寸,可应用于捕获吸光性颗粒。另外,利用离散傅立叶变换的平移原理实现空心光束实时平移,该方法可应用于实时操纵吸光性颗粒移动。 相似文献
19.
The paper presents an approach based on three-dimensional elastic equations to solve boundary-value stress problems for hollow cylinders with corrugated elliptical cross section. Discrete Fourier series are used to make the problem one-dimensional and then to solve it by the stable discrete orthogonalization method. Solutions for cylinders of different thicknesses are presented 相似文献
20.
H. M. Wang H. J. Ding Y. M. Chen 《Archive of Applied Mechanics (Ingenieur Archiv)》2005,74(9):581-599
The dynamic solution of a multilayered spherically isotropic piezoelectric hollow sphere subjected to radial dynamic loads is obtained. By the method of superposition, the solution is divided into two parts: one is quasi-static and the other is dynamic. The quasi-static part is derived by the state-space method, and the dynamic part is obtained by the method of separation of variables coupled with the initial parameter method as well as the orthogonal expansion technique. By using the quasi-static and dynamic parts, the electric boundary conditions as well as the electric continuity conditions, a Volterra integral equation of the second kind with respect to a function of time is derived, which can be solved successfully by means of the interpolation method. The displacements, stresses and electric potentials are finally obtained. The present method is suitable for a multilayered spherically isotropic piezoelectric hollow sphere consisting of arbitrary layers and subjected to arbitrary spherically symmetric dynamic loads. Finally, numerical results are presented and discussed. 相似文献