Impact of alternative fuel rheology on spraying process of small pressure-swirl atomizer

Malý, Milan; Janáčková, Lada; Jedelský, Jan; Jícha, Miroslav

doi:10.1063/1.4953725

Cited by 4 publications

(3 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This effect is less evident for fully developed spray at Z = 20 mm where the ID32 varies in poor correlation with R 2 = 0.27 as ID32 ~ µl 0.16 . This correlation has similar exponent as in [43] where a very similar atomizer was tested over a very wide viscosity range of oil-based fuels. For the simplex atomizers, other published data (e.g.…”

Section: Resultssupporting

confidence: 57%

Effect of nanoparticles concentration on the characteristics of nanofluid sprays for cooling applications

Malý

Moita

Jedelský

et al. 2018

J Therm Anal Calorim

View full text Add to dashboard Cite

show abstract

Section: Resultssupporting

confidence: 57%

Effect of nanoparticles concentration on the characteristics of nanofluid sprays for cooling applications

Malý

Moita

Jedelský

et al. 2018

J Therm Anal Calorim

View full text Add to dashboard Cite

show abstract

“…Benjamin [7] followed the work of Jones [5] and found inverse trends for the some parameters. Wimmer and Brenn [8] theoretically uncovered a relatively strong effect of the liquid viscosity on CD, which was experimentally confirmed later by Maly et al [9]. The internal flow characteristics, especially the air core stability, were investigated by a few authors.…”

Section: Introductionmentioning

confidence: 78%

Internal flow and air core dynamics in simplex and spill-return pressure-swirl atomizers

Malý

Janáčková

Jedelský

et al. 2017

Proceedings ILASS–Europe 2017. 28th Conference on Liquid Atomization and Spray Systems

Self Cite

View full text Add to dashboard Cite

It is well known that the spray characteristics of pressure-swirl atomizers are strongly linked to the internal flow and that an unstable air core may cause instabilities in the spray. In this paper, a 10:1 scale transparent Plexiglas (PMMA) model of a pressure-swirl atomizer as used in a small gas turbine is introduced. The internal flow was examined using high-speed imaging, laser-Doppler anemometry and computational fluid dynamics tools. The experimental and numerical results were analysed and compared in terms of the air core morphology and its temporal stability. Two different liquids were used, Kerosene-type Jet A-1 represented a commonly used fuel while p-Cymene (4-Isopropyltoluene) matched the refractive index of the Plexiglas atomizer body. The internal flow characteristics were set using dimensionless numbers i.e. the Reynolds number and Froude number. The flow test conditions were limited to inlet Reynolds numbers from 750 to 1750. Two atomizers were examined to represent a Simplex and Spill-return (SR) geometries. In a comparative manner, the SR atomizer features a central passage in the rear wall of the swirl chamber. The main advantage of this concept is that the fuel is always supplied to the swirl chamber at a high pressure therefore providing good atomization over a wide range of the injection flow rate. However, the presence of the spill orifice strongly affects the internal flow even if the spill-line is closed. The air core in the Simplex atomizer was found fully developed and stable. The SR atomizer behaved differently, the air core did not form at all, and the spray was therefore unstable. KeywordsInternal flow dynamics, Pressure-swirl, transparent nozzle, CFD Introduction Pressure-swirl (PS) atomizers are used in many applications where a large surface area of droplets is needed or a surface must by coated by a liquid e.g. combustion, fire suspension or air conditioning. PS atomizers are easy to manufacture, reliable and provide good atomization quality. They convert the pressure energy of the pumped liquid into kinetic and surface energy of the resulting droplets. The pumped liquid is injected via tangential ports into a swirl chamber, where it gains a swirl motion, under which it leaves the exit orifice as a conical liquid sheet. The centrifugal motion of the swirling liquid creates a low-pressure zone in the centre of the swirl chamber and generate an air core along the centreline. The flow inside the atomizer is rather complex; it is two-phase with secondary flow effects. There is a strong link between internal flow conditions and the resulting spray characteristics, however, not all aspects of the internal flow are well understood. Before the advent of computational fluid dynamics, a number of authors attempted to describe the internal flow by relatively simple analytical approaches. One of the first was presented by Taylor [1] which focused on an inviscid analysis using Bernoulli's equation and the principle of maximal flow. Taylor derived an equation for the discharge coeffi...

show abstract

“…The modification of spill-line geometry was tested [2,3], the breakup of liquid sheet was studied [4]. The usage of alternative fuels for atomization was investigated [5]. The effect of various geometries of the pressure swirl atomizers has been tested by many other researchers.…”

Section: Introductionmentioning

confidence: 99%

Replication of Pressure Swirl Atomizer by 3D Printing and Influence of Surface Roughness on the Atomization Quality

Cejpek¹,

Malý²,

Bělka³

et al. 2020

MATEC Web Conf.

Self Cite

View full text Add to dashboard Cite

The replication of atomizers by 3D printing technology is a new approach of producing the pressure swirl atomizers. The surface roughness of 3D printed products and manufacturing accuracy of the 3D printing process influence the atomization of the liquid. The high-speed visualization of a spray, produced by scaled 3D printed atomizer, was performed. The spray stability, cone angle and breakup length were determined. Scaled 3D printed atomizers were tested at equivalent pressures of 0.25, 0.5 and 1 bar. Non-dimensionless parameter, Reynolds number, was preserved for the scaled atomizer. The effect of the surface roughness of the tangential ports, swirl chamber and discharge orifice on atomization was assessed at non-scaled pressure swirl atomizer. The roughness of a swirl chamber was created by corundum and ballotin blasting. The inlet pressures of 2.5, 5 and 10 bar were tested.

show abstract

Impact of alternative fuel rheology on spraying process of small pressure-swirl atomizer

Cited by 4 publications

References 7 publications

Effect of nanoparticles concentration on the characteristics of nanofluid sprays for cooling applications

Effect of nanoparticles concentration on the characteristics of nanofluid sprays for cooling applications

Internal flow and air core dynamics in simplex and spill-return pressure-swirl atomizers

Replication of Pressure Swirl Atomizer by 3D Printing and Influence of Surface Roughness on the Atomization Quality

Contact Info

Product

Resources

About