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The hydrodynamic flow of an incompressible and isotropic Casson fluid through a yawed cylinder is investigated by employing continuity, momentum, and energy equations satisfying suitable boundary conditions. The density variation is governed by Boussinesq approximation. The model equations consisting of coupled partial differential equations (PDEs) are transformed by applying non-similar transformation relations. The set of transformed PDEs is solved using the analytical technique of homotopy analysis method (HAM). The impacts of varying yaw angle, and mixed convection and Casson parameters over fluid velocity (chordwise and spanwise components), its temperature, Nusselt number, and skin friction coefficients are investigated and explained through various graphs. It is found that the enhancing yaw angle, Casson parameter, and convection parameter augment the fluid velocity, heat transfer rate, and skin friction and reduce the fluid temperature. The agreement of present and published results justifies the application of HAM in modeling the mixed convective Casson fluid flow past a yawed cylinder.

Non-similar solutions are found numerically to a system of coupled non-linear partial differential equations indicating, unsteady laminar water boundary layer flow over yawed cylinder using implicit finite difference scheme along with Quasi-linearization technique. The fluid properties such as viscosity and Prandtl number are considered as an inverse function of temperature. Unsteadiness is caused by upstream velocity in and directions and non-uniform mass transfer (suc- tion/injection) which is applied through slot on the surface of the geometry. The effect of yaw angle, variable fluid properties and non-uniform mass transfer on skin friction and heat transfer coeffi- cients is analyzed. It is found that non-uniform slot suction and downstream movement of the slot cause the point of vanishing skin friction moves downstream, but non-uniform slot injection pro- duces the opposite result of that corresponding to the suction case. When the yaw angle increases, both the skin friction coefficient in the - direction and the heat transfer coefficient decrease but the skin friction coefficient in the - direction increases for all times. The effect of the yaw angle is very little on the point of vanishing skin friction. 2014 Production and hosting by Elsevier B.V. on behalf of Ain Shams University.

Local and average heat transfer coefficients were determined for a right circular cylinder in an oscillating flow. Spanwise platinum heater strips were used to heat the cylinder isothermally over the lower 180 degrees from the front to rear stagnation point. The four inch diameter cylinder was positioned both normal to and at 45 degrees to the flow direction. Data was gathered for diameter Reynolds numbers from 100,000 to 300,000. Large amplitude oscillations were imposed upon the mean flow using a rotating shutter arrangement. Frequencies of 0, 5, 10, 22, 50, 100 and 126 Hertz were investigated For normal flows, local heat transfer coefficients in the wake and average Nusselt numbers were enhanced above values for steady flow, for runs having large amplitude. In the 45° flows, no significant change in heat transfer was noted with oscillating flow. http://archive.org/details/localheattransfe1094520585 Lieutenant, United States Navy Approved for public release; distribution is unlimited.