TY - JOUR

T1 - Swirl flow in annular geometry with varying cross-section

AU - Shakeel, Mohammad Raghib

AU - Mokheimer, Esmail M. A.

N1 - KAUST Repository Item: Exported on 2022-05-25
Acknowledgements: For computer time, this research used the resources of the Supercomputing Laboratory at King Abdullah University of Science & Technology (KAUST) in Thuwal, Saudi Arabia. The support provided by the King Abdullah City for Atomic and Renewable Energy (K. A. CARE) is also highly acknowledged.
This publication acknowledges KAUST support, but has no KAUST affiliated authors.

PY - 2022/5/19

Y1 - 2022/5/19

N2 - Swirling gas flow is an important topic of research that helps in the design of rockets, atomizers,and gas turbine combustors. In the present work, swirl flow inside annular geometries with constant and varying cross-sectional areas are examined using computational fluid dynamics (CFD). Effects of changing the flow and geometric parameters on the swirl behaviour were studied. Reynolds number was found to increase the swirl number in straight and diverging cross-sectional geometries while no significant effect of Reynolds number was observed in converging cross-sectional geometry. Radius ratio, defined as the ratio of the inner to the outer radius of the annular geometry, was found to have a significant effect on the swirl number. Decreasing the radius ratio, in straight and diverging annular geometry decreases the swirl number, however, an opposite trend was observed in the case of converging annular geometry due to significant increase in axial velocity as a result of reduced cross-sectional area. Increasing the swirler vane angle increased the swirl number. At higher vane angles of 60° and 70°, a recirculation zone is developed near the exit of the swirler. Using small cone angles was found to lower the swirl decay rate in converging and diverging nozzles.

AB - Swirling gas flow is an important topic of research that helps in the design of rockets, atomizers,and gas turbine combustors. In the present work, swirl flow inside annular geometries with constant and varying cross-sectional areas are examined using computational fluid dynamics (CFD). Effects of changing the flow and geometric parameters on the swirl behaviour were studied. Reynolds number was found to increase the swirl number in straight and diverging cross-sectional geometries while no significant effect of Reynolds number was observed in converging cross-sectional geometry. Radius ratio, defined as the ratio of the inner to the outer radius of the annular geometry, was found to have a significant effect on the swirl number. Decreasing the radius ratio, in straight and diverging annular geometry decreases the swirl number, however, an opposite trend was observed in the case of converging annular geometry due to significant increase in axial velocity as a result of reduced cross-sectional area. Increasing the swirler vane angle increased the swirl number. At higher vane angles of 60° and 70°, a recirculation zone is developed near the exit of the swirler. Using small cone angles was found to lower the swirl decay rate in converging and diverging nozzles.

UR - http://hdl.handle.net/10754/678178

UR - https://www.tandfonline.com/doi/full/10.1080/19942060.2022.2076744

U2 - 10.1080/19942060.2022.2076744

DO - 10.1080/19942060.2022.2076744

M3 - Article

SN - 1994-2060

VL - 16

SP - 1154

EP - 1172

JO - Engineering Applications of Computational Fluid Mechanics

JF - Engineering Applications of Computational Fluid Mechanics

IS - 1

ER -