Analysis of natural convection heat transfer from a cylinder enclosed in a corner of two adiabatic walls

• Natural convection from a cold cylinder enclosed between two adiabatic walls is studied.
• Flow stream lines and isothermal lines depend on the cylinder spacing over the floors.
• For small spacing convection is strongly related to the space from the floor.
• Flow separate sooner when the horizontal floor is closer to the cylinder.
• More closer is the cylinder to the corner, more reduction in convection heat transfer is observed.

A steady two-dimensional laminar natural convection heat transfer from a cold single horizontal isothermal cylinder enclosed between two adiabatic walls is studied both experimentally and numerically. Experiments are performed to study the effects of cylinder distance from horizontal and vertical walls for Rayleigh numbers of 3 × 105 and 6 × 105. Numerical computations are carried out by solving the governing equations of laminar natural convection using the finite volume technique. OpenFOAM which is an open source code software is used. Computations are made for a wide range of Rayleigh numbers from 104 to 106 and different ratios of vertical cylinder spacing (L/D) and that of horizontal cylinder spacing (S/D). Comparisons are made with the corresponding experimental measurements. Flow streamlines and isothermal lines around the cylinder so that by changing the value of L/D and S/D, due to damping effects of the adiabatic walls, the cold plume moves away from the cylinder at different angles. Results also indicate that local and average heat transfer coefficient is highly affected by L/D and Rayleigh number while S/D has a limited influence on heat transfer from the tube.