Numerical investigation of multiple stationary and time-periodic flow regimes in vertical rotating disc CVD reactors

Abstract

The vertical rotating disc CVD reactor problem is revisited with a computational framework that allows systematic parameter continuation along branches of flow regimes over various operating parameter values. The commercial CFD code Fluent is used, enhanced with a home-made module and by appropriate initialization, a P–ω diagram is mapped out. In addition to the well known result where boyancy-induced and rotation-induced regimes exist for low and high rotation rates respectively along with a favorable for film uniformity plug flow regime in between, interesting new flow regimes are computed: Stable time-periodic buoyancy induced flows are found as well as stationary ones. Periodic buoyancy induced flows co-exist with stationary plug flow regimes over a range of ω for pressures higher than 200Torr. A regime of stationary flows where the effect of buoyancy and rotation is combined is computed at pressures higher than 350Torr and it shown to co-exist with typical rotation induced flows.