Axisymmetric nozzles with chamfered contraction

0477171 - ÚT 2018 RIV CH eng J - Journal Article
Tesař, Václav
Axisymmetric nozzles with chamfered contraction.
Sensors and Actuators A - Physical. Roč. 263, August (2017), s. 147-158. ISSN 0924-4247. E-ISSN 1873-3069
Institutional support: RVO:61388998
Keywords : nozzles * chamfering * invariant
OECD category: Fluids and plasma physics (including surface physics)
Impact factor: 2.311, year: 2017
http://ac.els-cdn.com/S0924424716310329/1-s2.0-S0924424716310329-main.pdf?_tid=f953dc4c-873c-11e7-b8d0-00000aacb35d&acdnat=1503408341_51527a384c272a3c4e8f43e6046d789d

Paper discusses experimental results obtained in measurements of essentially incompressible flows inaxially symmetric nozzles with inlet entrance shaped as a 45◦ half-angle chamfering. Interest was concentrated on low Reynolds number conditions. Six differently behaving flow regimes, from A to F, were identified. In the regimes B and C, of most importance for engineering applications, the nozzles exhibit lower hydraulic loss than comparable nozzles with smooth, rounded inlet. In the regime C were identified secondary invariants valid for the whole family of nozzles with different lengths. Most probably due to the de-stabilising effect of vortices, shed from the vortex rings formed at the sharpentrance edge made by the chamfering, at increasing Reynolds number the nozzles with chamfered inlet enter quite soon a transition into turbulence.
Permanent Link: http://hdl.handle.net/11104/0273618