Document Type

Conference Proceeding


Faculty of Health, Engineering and Science


School of Engineering




This article was originally published as: Thomas, B. K., Ahmed, Z. U., Al-Abdeli, Y. M., & Matthews, M. T. (2013). The Optimisation of a Turbulent Swirl Nozzle Using CFD. In Proceedings of the Australian Combustion Symposium (pp. 271-274). Sydney, Australia: Combustion Institute. Original article available here


Swirl is imparted into free and impinging nozzle flows as well as jet flames to affect convective heat transfer, fluid mixing or flame stability. At the nozzle exit plane, the emerging flow strongly influences downstream flow development and so factors which impact upon the emitted flow are worthy of study. This paper presents preliminary CFD analyses into the effect of design parameters and operational settings on the emerging flow at the exit plane for a swirl nozzle (Remax~30,500). The research was conducted in the premanufacture stage to optimise the nozzle. Swirl is aerodynamically generated using multiple tangential ports located upstream of the exit plane and the streamwise flow is augmented with flow from two axial ports located at the nozzle base. Before reaching the exitplane, all flows pass through a contraction en route to a straight section of length (L). Factors studied in this paper include the angle of (inlet) tangential ports, the total length of the straight section (L), the ratio of axial-to-tangential inflows and the Reynolds number. Results show that larger tangential port angles and a shorter straight section help develop a modestly greater