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111.
112.
针对高压汽水两相流实验中小液量测量困难这一问题,运用重力压差主要由液相密度决定的原理,提出了由圆管内重力压差变化线性分求流量的方法,实验表明这一方法线性度很好,本文对这一方法进行了理论分析,得到了计算修正公式,同时评估了计算带来的误差。 相似文献
113.
介绍了电磁轴承的基本组成,通过对电磁力的力学方程进行分析,提出了低偏置磁通控制的思想,并从功放的角度出发分析了低偏置电流工作的优点。经过仿真及实验,结果表明,这种方法对于减少功耗损失、获得满意的动态响应和高频动态性能方面是行之有效的。 相似文献
114.
A general method based on complex variable theory is proposed to determine the magnetic and elastic fields of a piezomagnetic
body. This method is used to derive the basic relations for complex potentials in the two-dimensional problem of magnetoelasticity,
their general representations for a multiply connected domain, expressions for stresses, displacements, vectors of magnetic
field intensity and magnetic flux density, and magnetic field potential. A closed-form solution is obtained for a body with
an elliptic (circular) hole or crack subjected at infinity to the action of a constant magnetoelastic field. Numerical results
for a piezomagnetic plate with a circular hole are presented
__________
Translated from Prikladnaya Mekhanika, Vol. 41, No. 10, pp. 64–74, October 2005. 相似文献
115.
Y.H. Hung Associate Professor S.W. Perng Graduate Student 《Experimental Thermal and Fluid Science》1988,1(4):305-313
A series of systematic experiments for measuring transient natural andforced convected heat fluxes in a one-sided heated vertical channel have beenconducted. The total heat input in transient natural and forced experiments iscomposed of four kinds modes: radiative heat loss, conductiveheat lossm, thermal capacity of the plate, and convective heat transfer in thetest channel. In the transient periods, the generalized correlations for estimatingtransient convective heat flux are proposed in natural and forced convectionexperiments. By using the proposed qc″ distributions, satisfactory agreementsare achieved between the transient Nux predictions and experimentaldata. 相似文献
116.
F.?S.?IbrahimEmail author M.?A.?Mansour S.?M.?Abdel-Gaied 《Transport in Porous Media》2005,61(1):45-57
The problem of natural convective heat transfer for a non-Newtonian fluid from an impermeable vertical plate embedded in a fluid-saturated porous medium has been analyzed. Non-Darcian, radiative and thermal dispersion effects have been considered in the present analysis. The governing boundary layer equations and boundary conditions are cast into a dimensionless form and simplified by using a similarity transformation. The resulting system of equations is solved by using a double shooting Runge–Kutta method. The effect of viscosity index n, the conduction–radiation parameter R, the non-Darcy parameter Gr*, the thermal dispersion parameter Ds and the suction/injection parameter fw on the fluid velocities, temperatures and the local Nusselt number are discussed. 相似文献
117.
Langevin stochastic differential equations provide a consistent basis for Reynolds stress, scalar transport and p.d.f. models. However, the stochastic equations must be capable of representing existing closures, like the General Linear Model, or the Rotta and Monin return to isotropy formulations. A consistent approach to derive both Reynolds stress and scalar flux transport equations, starting from a stochastic differential equation for velocity fluctuations, is presented here. A set of algebraic relations for the dispersion tensor is derived for homogeneous shear flow and for the log-layer. 相似文献
118.
We propose a new approach for the discretization of diffusive flux on a non orthogonal mesh based on the Deferred correction introduced by Peric. This new method is applied successfully to the solution of a Poisson problem in quadrangular domains meshed with very distorted control volumes. The interest of this approach lies in the fact that the precision of the used schemes is conserved despite meshes distortion level. The comparative study of the value of the spectral radius of iteration matrix enables us to explain why our Deferred correction approach is better than that of Peric, which diverges on highly skewed meshes. To cite this article: Y.M. Ahipo, Ph. Traore, C. R. Mecanique 334 (2006). 相似文献
119.
Tensor representation theory is used to derive an explicit algebraic model that consists of an explicit algebraic stress model (EASM) and an explicit algebraic heat flux model (EAHFM) for two-dimensional (2-D) incompressible non-isothermal turbulent flows. The representation methodology used for the heat flux vector is adapted from that used for the polynomial representation of the Reynolds stress anisotropy tensor. Since the methodology is based on the formation of invariants from either vector or tensor basis sets, it is possible to derive explicit polynomial vector expansions for the heat flux vector. The resulting EAHFM is necessarily coupled with the turbulent velocity field through an EASM for the Reynolds stress anisotropy. An EASM has previously been derived by Jongen and Gatski [10]. Therefore, it is used in conjunction with the derived EAHFM to form the explicit algebraic model for incompressible 2-D flows. This explicit algebraic model is analyzed and compared with previous formulations including its ability to approximate the commonly accepted value for the turbulent Prandtl number. The effect of pressure-scrambling vector model calibration on predictive performance is also assessed. Finally, the explicit algebraic model is validated against a 2-D homogeneous shear flow with a variety of thermal gradients. Dedicated to the memory of the late Professor Charles G. Speziale of Boston University 相似文献
120.
Pulsatile flow of a viscous fluid between two permeable beds is analyzed. The flow between and through the permeable beds are governed by the Navier-Stokes equations and Darcy's law, respectively. The velocity field and the volume flux are obtained for several cases and discussed. Further, when the permeability parameter k→0, the results agree with those of Wang (J. Appl. Mech. 38 (1971) 553). 相似文献