Forced convection heat transfer from a finite-height cylinder Articles uri icon

publication date

  • July 2014

start page

  • 171

end page

  • 187

issue

  • 1

volume

  • 93

International Standard Serial Number (ISSN)

  • 1386-6184

Electronic International Standard Serial Number (EISSN)

  • 1573-1987

abstract

  • This paper presents a large eddy simulation of forced convection heat transfer in the flow around a surface-mounted finite-height circular cylinder. The study was carried out for a cylinder with height-to-diameter ratio of 2.5, a Reynolds number based on the cylinder diameter of 44 000 and a Prandtl number of 1. Only the surface of the cylinder is heated while the bottom wall and the inflow are kept at a lower fixed temperature. The approach flow boundary layer had a thickness of about 10% of the cylinder height. Local and averaged heat transfer coefficients are presented. The heat transfer coefficient is strongly affected by the free-end of the cylinder. As a result of the flow over the top being downwashed behind the cylinder, a vortex-shedding process does not occur in the upper part, leading to a lower value of the local heat transfer coefficient in that region. In the lower region, vortex-shedding takes place leading to higher values of the local heat transfer coefficient. The circumferentially averaged heat transfer coefficient is 20 % higher near the ground than near the top of the cylinder. The spreading and dilution of the mean temperature field in the wake of the cylinder are also discussed.

keywords

  • large-eddy simulation; heat transfer; forced convection; finite-height cylinder; large-eddy simulation; circular-cylinder; cross-flow; coherent structures; boundary-layer; swirling jet; flat-plate; fluid-flow; les; matrix