Affordable Access

Publisher Website

Visualization of mixed convective vortex rolls in an impinging jet flow of air through a cylindrical chamber

International Journal of Heat and Mass Transfer
Publication Date
DOI: 10.1016/s0017-9310(02)00055-8


Abstract In this study a combined buoyancy and inertia driven vortex flow in an air jet impinging onto a heated circular plate confined in a cylindrical chamber simulating that in a vertical single-wafer rapid thermal processor for semiconductor manufacturing is investigated experimentally by flow visualization. A copper plate is used here to simulate the wafer for its better uniformity of the surface temperature and air is used to replace the inert gases. We concentrate on how the inlet gas flow rate, temperature difference between the wafer and air jet, and chamber pressure affect the vortex flow. The results show that typically the flow in the chamber is in the form of two-roll structure characterized by a circular vortex roll around the air jet along with another circular roll near the side wall of the chamber. Both rolls are somewhat deformed. The rolls are generated by the reflection of the jet from the wafer and by the deflection of the wall boundary layer flow along the wafer surface by the upward buoyancy due to the heated wafer. At low buoyancy and inertia the vortex rolls are steady and axisymmetric. At increasing buoyancy associated with the higher temperature difference and chamber pressure, the inner roll becomes slightly smaller and the outer roll becomes correspondingly bigger. Moreover, at a higher gas flow rate the inner roll is substantially bigger. Based on the present data, a correlation equation is provided to predict the location where the two rolls contact each other, providing the approximate size of the rolls. Moreover, at high buoyancy and inertia the flow becomes time dependent and does not evolve to a steady state.

There are no comments yet on this publication. Be the first to share your thoughts.


Seen <100 times

More articles like this

Effects of jet-to-disk separation distance on the...

on International Journal of Heat... Jan 01, 2005

Characteristics of vortex flow in a low speed air...

on International Journal of Heat... Jan 01, 2003

Unstable vortex flow and new inertia-driven vortex...

on International Journal of Heat... Jan 01, 2006

A further investigation of effects of jet-disk sep...

on International Journal of Heat... Jan 01, 2009
More articles like this..