1.

     The 'psi'-'omega' form of modified Navier-Stokes (NS) equations are solved numerically for a two dimensional peristaltic flow under the influence of transverse magnetic field. A simple nonlinear and non-iterative streamline quadrature upwinding 'psi'-'omega' finite element method (FEM) is employed in the flow analysis. The velocity, pressure and stress fields of various peristaltic flows under the influence of transverse magnetic fields are obtained. Effects of the magnetic field are brought out by comparing these results with those of the peristaltic flow free from the influence of magnetic field. Under the influence of magnetic field velocities near the central axis decrease while those near the wall tend to increase, streamlines shift downwards, wall pressure distribution becomes antisymmetric and favours mixing and transporting of the fluid, and wall shear stress decreases considerably.

2.

     Aerosol aggregates with ramified or net-like structure are usually found in the atmosphere. However, a comprehensive understanding of the hydrodynamic behavior of the aggregates has not been well established. In this study, collapsed silver aggregates with fractal dimension (D_f) ranging from 2.6 to 2.9 were generated by controlling the degrees of collapse. The ratio of hydrodynamic radius (R_h) to the radius of gyration (R_g) of the aggregates was calculated from the experimental measurements. It is shown that the ratio of R_h/R_g reaches an approximately constant value of 1.05 for aggregates with fractal dimension in this range.

3.

     Basic research on oscillating plug flow of a magnetic fluid at low frequency is made as one of engineering applications for a micro sensing actuator. Magnetic and temperature fields have been applied to the device of the actuator. The magnetization of the magnetic fluid depends strongly on the temperature. At a low frequency range the amplitude of the oscillating plug flow is controlled more effectively by using temperature change of the magnetic fluid. The dynamic characteristics of the magnetic fluid actuator, especially the frequency response curve of amplitude, is investigated theoretically taking into account aggregation of particles. The basic experiment is conducted using a simple experimental apparatus for oscillating plug flow at low frequency. It follows from the theoretical and experimental results that the particle aggregates play an important role in the dynamic characteristics of the actuator.

4.

     Mass transport between the arterial wall and blood is believed to play an important role in the initiation of atherosclerosis. Arterial branches are found to be one of the most common sites for the occurrence of the disease. This paper investigates the mass transport rate across the arterial wall using a simplified two-dimensional model of a symmetrically branched channel. It is found that the mass transport rate is greatly reduced on the side wall of the branch where the shear rate is low. The dependence of the mass transport rate on the area ratio of the branching channel, as well as the branching angle, Reynolds and Schmidt numbers, is also investigated.

5.

     Basic research is made on the effect of flow rate, nonuniform magnetic and temperature fields on thermohydrodynamic characteristics of energy conversion system by using magnetic fluid whose magnetic properties are susceptible to temperature in applying magnetic field. Experimental study is conducted for two cases of open and closed test loops. The experimental data of pressure difference are compared with the theoretical results taking into account the particles aggregation of the magnetic fluid in the applied magnetic field region. The effects of flow rate, the amplitude and the direction of the magnetic field and temperature difference on the pressure difference are clarified in relation to the increment of apparent viscosity of the magnetic fluid by application of magnetic field.

6.

     The free convection boundary layer flow of a viscous, incompressible and electrically conducting fluid along an isothermal vertical wavy surface in the presence of a transverse magnetic field is discussed. A sinusoidal surface is used to elucidate the effects of the magnetic field and the amplitude of the wavy surface on the velocity and temperature fields as well as on the local rate of heat tran{fer. The results are shown graphically for different values of the magnetic field parameter M, amplitude of the wavy surface a, and the Prandtl number Pr.

7.

     The linear stabili|y of the Couette flow of viscoelastic liquid in an annular gap is analysed theoretically, using the viscometric Criminale-Ericksen-Filbey equation. The stability limit is discussed with reference to the viscometric functions: viscosity, primary and secondary normal stress difference coefficients. The form of the secondary normal stress difference function has a considerable influence on the stability limit. The resuls of this work are in good agreement with the theoretical predictions for the Edward-Doi and generalized Maxwell models.

8.

     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. Based on a first-order perturbation solution in the modified Reynolds number an analysis is presented to determine the effect of the fluid film inertial forces on the dynamic properties of a flow field. The results are presented for the velocity components and the pressure distribution for typical shapes of surfaces as two disks and two spherical surfaces.

9.

     This work discusses heat transfer for pseudoplastic and yield fluids. The tested geometry consists of two coaxial cylinders, the outer one being subject to a constant heat flux density, the inner core being able to rotate around its axis. Semi empirical-correlations are proposed so as to predict the intensity of heat transfer for these particular fluids. Moreover, we compare the obtained results with the previous ones concerning a smilar measuring cell with a lower aspect ratio and also with those relative to a real scraped surface heat exchanger, the dimensions of which being exactly the ones of our device.