Mixed convection boundary‐layer flow from a horizontal circular cylinder in micropolar fluids: case of constant wall temperature

The laminar mixed convection boundary‐layer flow of a micropolar fluid past a horizontal circular cylinder in a stream flowing vertically upwards has been studied in both cases of a heated and cooled cylinder. The solutions for the flow and heat transfer characteristics are evaluated numerically for different parameters, such as the mixed convection parameter λ, the material parameter K (vortex viscosity parameter) and the Prandtl number Pr=1 and 6.8, respectively. It is found, as for the case of a Newtonian fluid considered for Pr=1, that heating the cylinder delays separation and can, if the cylinder is warm enough, suppress it completely. Cooling the cylinder, on the other side, brings the separation point nearer to the lower stagnation point and for sufficiently cold cylinder there will not be a boundary‐layer on the cylinder. This model problem may solve industrial problems with processing of polymeric liquids, lubricants and molten plastics.