The problem of determining the slow viscous flow of a fluid past a cylinder with an arbitrary cross section, in a domain with boundary limited by a plane wall, is formulated as a system of Fredholm linear integral equations of the second kind. We next complete the double-layer potentials of the system with some terms having singularities located inside the obstacle and which satisfy the nonslip boundary condition on the wall. We next prove that this system of integral equations has a unique continuous solution when the boundary of the particle is a Lyapunov curve. Also, the numerical results are given for the case of a fixed circular obstacle. For the numerical solution we use a standard boundary element technique.

     An analysis is presented for the heat transfer in a micropolar fluid boundary layer over a flat plate with uniformly distributed vectored surface mass transfer. Numerical solutions for the governing nonsimilar boundary layer equations are presented for a range of values of the material properties and Prandtl number of the fluid. The results indicate that the micropolar fluids display a reduction in drag as well as heat transfer rate when compared with Newtonian fluids.

     In a finite element method for an incompressible Navier-Stokes equation, the divergent, gradient, simplified, and mixed schemes are applicable to discretize the advection term. The simplified scheme substitutes the average velocity in each element for the advection velocity, and the mixed scheme is a combination of the divergent and gradient schemes. This paper investigates the effects of these schemes on the computational accuracy and CPU time of a finite element method based on the SMAC method. The investigations are accomplished by solving the flow in a square cavity for the cases in which the velocity field is calculated by the mass-lumping and multi-pass algorithms. The computational accuracy is higher in the order of divergent, mixed, gradient, and simplified schemes, irrespective of the solution algorithms for the velocity. The divergent scheme, allowing calculation with the shortest CPU time, is the most useful among the four schemes. The improvement in computational accuracy produced by the multi-pass algorithm is independent of the discretization scheme of the advection term.

     Stiffened shell has been analyzed on the basis of a combination of Allman's plane stress triangle and DKT plate bending element. As the same displacement function is used for both the shell and the stiffener element, the compatibility condition at the shell beam junction is ensured. The formulation of the stiffener is done in such a manner that it can be placed anywhere within the shell element. The applicability of this element is tested for different structures, particularly for shallow and deep shells.

     In offshore oil field development, we foresee an increase in the demand for oil - well pumps having improved gas handling capacity. To meet the demand by improving the performance of a radial-flow centrifugal pump of low specific speed, many kinds of impellers, fabricated by changing systematically the design parameters, such as discharge angle, location and shape of leading edge, number of blades, location of the split for dividing the blade length into two parts and so on, were experimentally investigated under air-water two-phase flow conditions to clarify the parameters on pump performance. The optimum blade is found to be one that has a split in the latter half of the impeller and is installed with discharge angle of approximately 90^o.

     A contravanant velocity based incompressible Navier-Stokes governing system is derived to generate an implicit multi-level method so that we can simulate the receptivity and flow transition in cases with complex geometnes. The two- and three- dimensional development of leading-edge receptivity and flow transition in a 2-D Joukowsky airfoil boundary layer are investigated by direct numencal simulation (DNS) using this system. The numencal investigation is based on the so-called spatial approach. The numencal results agree very well with linear stability theory (LST) and the experimental results for the flat plate case. They also agree well with the result obtained by other researchers for the 2-D elliptic leadingedge receptivity case. Some new phenomena for the transition around Joukowsky airfoils are abserved. The details of this approach are described.

     The thermosolutal convection in Rivlin-Ericksen fluid in porous medium is considered in the presence of uniform vertical magnetic field. For the case of stationary convection, the stable solute gradient and magnetic field have stabilizing effects on the system, whereas, the medium permeability has destabilizing effect on the system. The kinematic viscoelasticity has no effect on stationary convection. The stable solute gradient and magnetic field introduce oscillatory modes in the system, which were non-existent in their absence. The sufficient conditions for the non-existence of overstability are also obtained.

     In the present paper, mass transfer effect on the unsteady free-convective flow of an incompressible viscous fluid between two vertical parallel plates is discussed for impulsive start of one of the plate. Expressions for velocity, temperature and concentration are obtained by the Laplace transform technique. The influence of the Prandtl number (Pr), Schmidt number (Sc) and time parameter (t) on velocity field and skin-friction are discussed extensively.