02465nas a2200241 4500008004100000022001400041245006600055210006500121260006800186300001400254490000700268520169600275653000801971653001401979653001801993653002102011653001702032100002302049700001902072700001502091700002002106856009702126 2008 eng d a0001-154100aFlow pattern in vortex diode: experiments and CFD simulations0 aFlow pattern in vortex diode experiments and CFD simulations a111 RIVER ST, HOBOKEN, NJ 07030 USAbJOHN WILEY & SONS INCcMAY a1139-11520 v543 a

Vortex diodes are used as leaky nonreturn valves in applications, where it is desirable to avoid valves with moving parts. Despite their use in practice for several decades, no detailed analysis of the flow inside the vortex diodes is available. A strategy was derived for the CFD simulations of the vortical flow in diodes. A good agreement was seen between pressure drop (Delta P) across the inlet-outlet ports from CFD simulations, and the experimental data for five diode sizes. The simulations showed that in the reverse flow situation tangential velocity was dominant and resulted in conservation of angular momentum in the chamber until it reaches the axial exit port. This vortical motion induced a significant pressure drop (Delta P-r). The axial velocity gradient over the chamber cross-section helps in inducing relaminarization of the flow. In the forward flow mode, the fluid gets distributed radially over the chamber and exits through the tangential port, yielding low Delta P-f. The analysis showed that the performance of a diode is strongly affected by diode geometry, size, aspect ratio, nozzle configuration and Reynolds number. Among different configurations, the nozzles with entry port size equal to diode yielded higher diodicity. Simulations showed that using angle of divergence for diffuser sections of nozzles of the order of 7 degrees exhibited higher diodicity than smaller angles. It was also observed that at higher flow rates significantly higher diodicity was obtained using axial nozzles with larger radius of curvature for expander section. The modeling methodology and results presented will be useful for evolving better designs of vortex diodes.

10aCFD10aDiodicity10apressure drop10arelaminarization10aVortex diode1 aKulkarni, Amol, A.1 aRanade, V., V.1 aRajeev, R.1 aKoganti, S., B. uhttps://library.ncl.res.in/content/flow-pattern-vortex-diode-experiments-and-cfd-simulations01803nas a2200241 4500008004100000022001400041245007400055210006900129260010600198300001400304490000700318520096800325653001701293653001401310653001201324653001801336653001701354100002301371700002201394700001501416700002001431856011001451 2009 eng d a0009-250900aPressure drop across vortex diodes: experiments and design guidelines0 aPressure drop across vortex diodes experiments and design guidel aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcMAR a1285-12920 v643 a

Vortex diodes are used as leaky non-return valves in applications where it is desirable to avoid valves with moving parts. Despite their use in practice for several decades, no clear guidelines for design and optimization of vortex diodes are available. Detailed experimental study on flow and pressure drop characteristics of vortex diodes was therefore carried out to evolve such guidelines. The study covered a wide range of vortex diodes. The variation of diodicity (ratio of pressure drop for reverse and forward flow for the same flow rate) with respect to diode geometry, diode size (d(c)), aspect ratio (d(c)/h), nozzle configuration and Reynolds number (Re) was studied. The experimental results were critically analyzed to develop a design methodology. The methodology is shown to be useful for obtaining the diode dimensions that would yield the desired diodicity for the required operating flow rate. (c) 2008 Elsevier Ltd. All rights reserved.

10aAspect ratio10aDiodicity10aNozzles10apressure drop10aVortex diode1 aKulkarni, Amol, A.1 aRanade, Vivek, V.1 aRajeev, R.1 aKoganti, S., B. uhttps://library.ncl.res.in/content/pressure-drop-across-vortex-diodes-experiments-and-design-guidelines-002348nas a2200253 4500008004100000022001400041245006200055210006200117260000800179300001200187490000700199520157700206653002301783653001301806653001401819653001701833653001501850100002801865700002401893700003201917700002601949700002201975856009701997 2018 eng d a1944-744200aSolvent degradation studies using hydrodynamic cavitation0 aSolvent degradation studies using hydrodynamic cavitation cJAN a295-3040 v373 a

Hydrodynamic cavitation for the degradation of organic solvents was investigated in detail using a newer form of cavitating device-vortex diode. The results were also compared with that using conventional cavitating device orifice. Removal of three different organic solventsacetone, methyl ethyl ketone (MEK), and toluene were studied on a pilot plant with capacity of 1m(3)/h. The effect of different operating parameters such as inlet pressure, initial concentration, and reactor type on the degradation rate of solvent was investigated in detail. The results revealed that efficiency of solvent removal varies substantially with the change in physical operating conditions and nature of the solvent. It was found that up to 80% degradation could be achieved for toluene (cavitational yield 32.2 x 10(-3) mg/J), substantially higher than that for acetone and MEK indicating the effect of molecular weight/structure in the degradation process. Further, the results clearly indicated chemical oxidation as a predominant mechanism for degradation and not physical destruction. Vortex diode that works on the principle of vortex generation for cavitation, was found to be far superior over conventional cavitating device-orifice- approximate to up to eight times higher cavitational yield could be obtained for toluene as compared to orifice. The results of this study provide newer insight into solvent removal using hydrodynamic cavitation and would have bearing on the treatment of solvent containing wastewaters. (C) 2017 American Institute of Chemical Engineers

10aEffluent treatment10aindustry10apollution10aVortex diode10awastewater1 aSuryawanshi, Pravin, G.1 aBhandari, Vinay, M.1 aSorokhaibam, Laxmi, Gayatri1 aRuparelia, Jayesh, P.1 aRanade, Vivek, V. uhttps://library.ncl.res.in/content/solvent-degradation-studies-using-hydrodynamic-cavitation