Modelling of heat transfer and fluid flow for decaying swirl flow in a circular pipe

Abstract

In the present study, a propeller type swirl generator was developed, and its effects on heat transfer and fluid flow were investigated numerically and experimentally for air flow in a pipe. In the numerical study, for axisymetrically, incompressible turbulent swirl flows, the Navier-Stokes equations were solved using the k- ε turbulent model. So that a computer program in Fortran was constructed using the SIMPLEC Algorithm. In experimental work, axial and tangential velocity distributions behind the swirl generator were measured by using hot-wire anemometry. Experimental and numerical axial and tangential velocity distributions along the pipe were compared, and good agreement was found. Axial velocity profile showed a decrement in the central portion of the pipe and an increased axial velocity was seen in near the wall. Tangential velocity profiles had a maximum value and its location moved in radially with distance. The effects of swirl flow on the heat transfer and pressure drop were also investigated experimentally.