Transient natural convection flow between vertical concentric cylinders heated/cooled asymmetrically

This paper investigates the impact of asymmetric heating or cooling of cylinder surfaces on transient natural convection flow in between vertical concentric cylinders. The outer surface of inner cylinder is assumed to be heated with temperature greater than the cooled inner surface of the outer cylinder. Closed form expressions are obtained by using the well-known Laplace transform technique to solve the governing partial differential equations in Laplace domain, whereas the Riemann-sum approximation is used to invert to time domain. Results show that the role of buoyancy force distribution parameter is to increase temperature, velocity, skin-friction and volume flow rate for both air and water. Further, reverse flow formation can be controlled by using suitable buoyancy force distribution parameter.