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     In this paper the authors present a solution to the problem of an inertia effect of lubricant flow in a multilobe conical bearing. The problem was solved by Galerkin's method after assuming that the bearing is lubricated with an incompressible Newtonian fluid. The general form of solutions for particular cases of the bearing geometry are given.

3.

     The influence of surface roughness on friction is considered in a model which allows us to describe the motion of atoms in terms of a deformation field applied at the surface. Roughness can be of two origins: topological and stochiometrical when chemisorbed atoms at the surface are taken into account. Its temperature and pressure dependence is studied. Friction in premelting phases is also discused.

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     A steady laminar flow of an incompressible Newtonian fluid is considered, in a narrow space between two surfaces of revolution, rotating with generally different angular velocities about a common axis of symmetry. The problem statement for two classes of throughflow, with full and rotational inertia, is formulated. A procedure for perturbing a creeping flow solution and an iteration scheme are developed to produce a solution for higher approximations. The solution depends on six or five parameters and is asymptotic in the sense of its good convergence in the second approximation for both classes of throughflow. Results are presented for the velocity components, the pressure and the mean temperature distributions for typical shapes of surfaces as disks and spherical surfaces, and are asymptotic in the sense of their good convergence in the second approximation for both classes of throughflow.

7.

     This paper proposes a design method which simultaneously chooses the dimensions and locations of the electromagnetic bearings and the diameter of the rotor shaft. We first derive the model of the electromagnetic bearing-controlled rotor system, and then reformulate the system's equations of motion in state space form. A criterion based on minimizing the rotor response and the control current is used to seek the optimum bearing dimensions. This criterion requires us to solve the Riccati equation. Constraints on the peak rotor time response, the control current, and the flux density of the bearing's stator are considered in this study. The sensitivity of the cost function and the constraints is also analyzed. Numerical analysis shows the superiority of this design methodology.

8.

     A generalised transformation method has been applied to solve the problem of pressure drop predictions for the laminar and the turbulent flow of power-law non-Newtonian fluids through curved pipes with a circular cross section. It has been shown that the variation of the modified friction index of any purely viscous Ostwald-de Waele fluid in a coiled tube for modified Dean number can be predicted by the proposed generalised Ito's equations. Experiments on the flow of aqueous solutions of hydroxypropylmethyl-cellulose and methylcelullose through curved pipes with various curvature ratios have been carried out. Very good agreement was found to exist between the theory and experiment.

9.

     The paper examines theoretically the solidification process of a viscous and heat-conducting liquid flowing in a cooling plane channel. The liquid flow is forced by a changeable pressure on the entry of the channel. The dimensionless differential equation of the liquid motion is obtained in the course of the conservation equations. The sample model of the pressure function and numerical calculations of the flow are presented. The paper discusses the influence of the cooling conditions as well as the pressure function on the solidification process. The dependence both of the dimensionless flow velocity and the dimensionless maximum flow distance on the pressure and the cooling conditions nondimensional parameters are presented in the figures.

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