The edge effect on the electrode faces upon testing of orthotropic media

The features of the fields in the peripheral regions of attachable capacitors are studied, in particular, on the faces of the strip electrodes where the field is not plane-parallel. A method for consideration of the contribution of the field on the electrode faces to the capacitance of the attachable capacitors is developed. An algorithm for prevention of the edge effect that influences the test results is considered for materials with uniaxial anisotropy. The effective values of the permittivity tensor components of the dry flax fiber are determined.     

Analytical solution of wave propagation in a non-homogeneous orthotropic rotating elastic media

In this paper, the natural frequencies of the radial vibrations of a hollow cylinder and hollow sphere with different boundary conditions under influences of rotation and non-homogeneity have been studied. The radial vibrations of orthotropic material as affected by the angular velocity are investigated on the basis of the linear theory of elasticity. The of elastodynamic equations have been solved in analytical form. Numerical results are given and illustrated graphically for each case. Comparisons are made with previous results which given in the absence of rotation and non-homogeneity. The results indicate that the effect of rotation and non-homogeneity is very pronounced.     

Three-dimensional real-time imaging of bi-phasic flow through porous media

We present a scanning laser-sheet video imaging technique to image bi-phasic flow in three-dimensional porous media in real time with pore-scale spatial resolution, i.e., 35 μm and 500 μm for directions parallel and perpendicular to the flow, respectively. The technique is illustrated for the case of viscous fingering. Using suitable image processing protocols, both the morphology and the movement of the two-fluid interface, were quantitatively estimated. Furthermore, a macroscopic parameter such as the displacement efficiency obtained from a microscopic (pore-scale) analysis demonstrates the versatility and usefulness of the method.     

一种新型过滤装置——高速离心式油液净化设备

现在飞机大量采用高精度液压伺服系统,因此,液压系统污染控制越来越重要.如何高效快速地滤除油液中的污染物, 直接关系到飞机作战效能的发挥.高速离心式油液净化设备利用离心原理滤除油液中的污染物,具有净化速度快,精度高,纳污容积大等优点.     

A cellular automata convection-diffusion model of flows through porous media

A cellular automata model is proposed for investigating the process of formation and percolation of gas or fluid flows through interstices in solid media. The model is a cellular automata analogy of a convection-diffusion equation in partial derivatives. The advantage of the model is that it allows a simple representation of boundary conditions and, thus, makes it possible to investigate properties of media with a complex pore configuration. Moreover, using probabilistic transition rules makes it possible to adapt to the properties of the boundaries between liquid and solid phases. A formal representation of the model is given. Results of experimental investigation for a medium with hydrophobic, hydrophilic, and neutral pores are presented.     

基于加压水平过滤的压滤系统改造分析

主要以加压水平过滤成饼机理为理论基础,阐述了传统水平过滤及进行改进后的加压过滤装置的原理,结合目前同忻选煤厂生产现场实际生产条件,应用改进后的加压水平过滤装置,能够提升过滤效率,使选煤厂的过滤系统在系统结构、能耗、经济等方面得到提高.     

Dielectrometry of orthotropic textile materials

The model of an attachable electrocapacitance screened transducer was considered. The direct and inverse problems were solved and the inspection zones of a transducer and also its optimal construction parameters that provide a high sensitivity to anisotropy in the dielectric properties of orthotropic materials were determined. The effective dielectric permittivity of a flax fiber was studied at different humidities depending on the frequency of an electromagnetic field oriented along or across the fiber. A dielectrometric method for evaluating the quality of a flax fiber was developed.     

Flexure of orthotropic rotating disks

The influence of off-set in mounting the blades on the disk, termed “eccentricity”, and the centrifugal stiffening on the stresses and deflection induced in laterally loaded orthotropic disks of variable thickness is analysed. The analysis is based on a series solution for the differential equation governing the deflection of the disk. Numerical results showing the effects of anisotropy, eccentricity and rotation on the stresses and deflection of the disk are presented graphically. It is shown that the stress due to radial bending moment reduces significantly with the increase in the degree of anisotropy.     

Nonlinear analysis of rectangular orthotropic plates

The present study deals with the large deflections and nonlinear flexural vibrations of orthotropic rectangular plates. In this paper, generalized double Fourier series in terms of generalized beam eigenfunctions for deflection and force functions are presented. The influences of aspect ratio, material properties, transverse load, rotational edge restraint coefficients, and two types of in-plane conditions are studied. The results of deflection and frequency ratio for special cases are compared with those values given in the literature and good agreement is obtained.     

Rational analysis of orthotropic bridge decks

New formulae are presented for the exact elastic analysis of a broad class of orthotropic bridge decks and panels in the form of ribbed plates. The formulae are directly applicable to decks that are simply supported at the ends and beam-supported at the sides and, through superposition, can be routinely extended to decks that are continuous over intermediate supports. The formulae are derived via a macro-discrete field approach, using mathematical models in the form of integral-summation equations.     

Postbuckling analysis of rectangular orthotropic plates

The postbuckling analysis of orthotropic simply supported rectangular plates of symmetric cross-section is studied and curves of load-shortening and effective widths are presented for various cases of orthotropic plates having different elastic properties. The results obtained are compared with results already published.     

Puradyn精密过滤装置

该文介绍了一种新型滤油器，采用原棉为滤芯材料，运用旁通过滤系统，设置了蒸发室加热片及添加剂释放块，使这种过滤器具有独特的优点。     

助滤剂在金属丝网过滤中的应用研究

助滤剂是过滤介质的一种,大多是分散的颗粒状物质,常用的有硅藻土、珍珠岩和纤维素等.根据过滤操作的实际需要选择适宜的助滤剂对提高过滤效率、延长滤材使用寿命是十分有益的,而助滤剂的比阻和可压缩性是选择助滤剂的根本依据之一.     

旋管过滤中过滤压差的计算与试验研究

通过对过滤装置内径向压力分布的分析,求出了过滤压差的计算式,清水透过实验表明,利用求出的计算式可以较好地预测过滤压差。     

Anti-plane elastodynamic analysis of a cracked orthotropic strip

Stress analysis is carried out in an orthotropic strip containing a Volterra-type screw dislocation. The distributed dislocation technique is used to construct integral equations for an orthotropic strip weakened by multiple smooth cracks under time-harmonic anti-plane deformation. These equations are of Cauchy singular type at the location of dislocation, which are solved numerically to obtain the dislocation density on the faces of the cracks. The dislocation densities are employed to determine stress intensity factors for multiple smooth cracks under anti-plane deformation. Several examples are solved and the stress intensity factors are obtained. The effects of the geometric parameters, cracks location and orientation on the stress intensity factors of cracks are investigated.     

Two-dimensional hyperbolic heat conduction in an orthotropic medium

Many natural and man-made materials have the properties of varying thermal conductivity with directions. In the present work, the very short-time temperature response characteristics are examined by using a hyperbolic heat conduction model in an orthotropic medium when an axially symmetric heat flux with a temporal profile, which is either continuous or activated for period Δt, is applied. The ratio of the thermal conductivities is one of the important parameters to be considered. The non-Fourier temperature responses in the orthotropic medium are compared with those in the isotropic case. The Fourier's results are also included and compared with the non-Fowrier's results.     

Analysis of orthotropic bearing non-linearity using non-linear FRFs

Among other critical conditions in rotor systems the large non-linear vibration excited by bearing non-linearity causes the rotor failure. For reducing this catastrophic failure and predictive detection of this phenomenon the analysis of orthotropic bearing non-linearity in rotor system using higher order frequency response functions (HFRFs) is conducted and is shown to be theoretically feasible as that of non-rotating structures. The complex HFRFs based on the Volterra series are newly developed for the process and investigated their features by using the simple forms of the FRFs associated with the forward and the backward modes.     

无耗材过滤系统

1 引言 传统的油过滤及各种冷却液的污染处理,都是使用各种化工材料,纸质材料,硅藻土或添加剂来达到目的.随之带来的问题是滤材和介质(油或冷却液)的频繁更换,系统的定期维护,费用也累积增加,并由此引发一些环境问题.随着石油及煤炭能源的日趋紧张,各种化工材料的价格会逐步高涨,企业的成本也会随之增加.因此,找到一种替代的方法已成为当务之急.本人在工程实践中设计开发了此文介绍的在线式过滤系统.它的特点是不使用耗材,低能耗,无污染,自动过滤介质中的杂质,几乎不用维护,最大限度地降低了生产成本.     

中国力学学会流体控制专业委员会第12届流体动力与机电控制工程学术会议召开

1 引言 传统的油过滤及各种冷却液的污染处理，都是使用各种化工材料，纸质材料，硅藻土或添加剂来达到目的。随之带来的问题是滤材和介质（油或冷却液）的频繁更换，系统的定期维护，费用也累积增加，并由此引发一些环境问题。随着石油及煤炭能源的日趋紧张，