Study of the Flow Characteristics of Swirling Confined Jet

International Journal of Research and Scientific Innovation (IJRSI) | Volume VI, Issue XII, December 2019 | ISSN 2321–2705

Study of the Flow Characteristics of Swirling Confined Jet

Md. Mosharrof Hossain¹, Muhammed Hasnain Kabir Nayeem^2*, Md Abu Taher Ali²

¹Department of Mechanical Engineering, Bangladesh University of Engineering and Technology (BUET), Dhaka-1000,  Bangladesh
²Department of Aeronautical Engineering, Military Institute of Science and Technolog (MIST), Dhaka-1216, Bangladesh
*Corresponding author

Abstract:- Axial mean velocity is the primary criteria of most of the flow field. In the present investigation, the mixing of swirling jet within the solid boundary and the wake position memory as it came out of the solid boundary was studied. Extension tubes of 105mm, 210mm and 315m length were fitted to 30 degree and 60 degree swirling nozzle which were made by fitting triangular shaped double start wedge shaped helical right hand thread inside the pipe nozzle. Height of these wedges were 27.5mm, leaving a clear opening of 25mm diameter in the central zone of the 80mm diameter pipe nozzle. Data of axial mean velocity at the exit of the extension tubes were recorded at Reynolds number 5.3e4.

Keywords—swirling, wedge-shaped, sinusoidal, helix, saddle-shaped, central.

I. INTRODUCTION

Both in nature and engineering fields one confronts with various types of flow situation viz boundary layer flows, free shear layer flows, wake flows, flow around bluff and streamline bodies, flow through pipes and ducts, flow through turbo-machines, jet flows and many others. Again, each of the flow types may confront with varieties and free jet. These jets may be without swirl and with swirl.
While the jets are used extensively to create thrust of aircraft and rocket engines, the swirling jets are used as a means of controlling flames in combustion chambers and have also found applications in various types of spray guns, burners, heat exchangers, cyclone separators mixing process etc. In turbulent swirling jet the tangential velocity components combine with the axial one making the flow field complex in nature and enhance the mixing of different flow particles present in the flow field.

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