Effect of axisymmetric forcing on the structure of a swirling turbulent jet

Алексеенко, С. В.; Дулин, В. М.; Kozorezov, Yuriy S.; Маркович, Д. М.

doi:10.1016/j.ijheatfluidflow.2008.07.005

Cited by 49 publications

(35 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…T he drops in bo th Nustag and Numean at high nozzle to surface distances is indica tive of the spread of the swirling impinging jets, as discussed in previous studies [58,69], This would lead to less effective heat dissipation by the impinging jets at th e stag nation point and supports th e idea of recirculation of warm fluid towards th e axis of the jet. In the next chapter, the flow field for th e different jet configurations will be explored, with a view to providing further insight into th e convective heat transfer characteristics of th e conventional and swirling impinging jets.…”

Section: Figure 58: Nusselt Number At R/d=0 For Swirlin^g Impinging supporting

confidence: 76%

“…The flow from each of these jets was seen to have a large radial dispersion as the distance from th e jet nozzle increased, corresponding w ith past research [58,73,84]. The other two generators examined, and Sno, which are the equivalent of the previous two generators w ithout the swirl core in their design, were found to have similar flow characteristics, nam ely a concentration of the seeding used to visualise the flow' at the outside of the jet.…”

Section: Onclud Ing R Em Arkssupporting

confidence: 53%

“…Alekseenko et al [58] shown in figure 2.29. Such similarities include th e breakdown of the je t structure and increase in the spread of the jet radially outw ard as the swirl num ber is increased.…”

Section: Contoured Nozzle Geom Etry With Axial Vanesmentioning

confidence: 92%

“…This research was continued by Alekseenko et al [58] who applied an external force on th e swirling flow which succeeded in increas ing the turbulence levels significantly for low swirl numbers. Examples of the flow' visualisation produced by Alekseenko et al [58] next to th e swirling jet geom etry used are displayed in figure 2.29. The images correspond well to those from Toh et al [62] shown in figure 2.26.…”

Section: Im P In G In G J E T H E a T T R A N S F E Rmentioning

confidence: 98%

“…The level of swirl is conmionly described by the swirl number, S, which is calculated by comparing the axial flux of angular momentum, G^>, with the axial flux of axial momentum, Gx, as shown in equations 2.4 and 2.5, described by G upta et al [57] and Alekseenko et al [58]. A swirl number of zero is equivalent to a conventional jet.…”

Section: Figure 224: Illustration O F Fluid (A) Suction and (B) Ejecmentioning

confidence: 99%

See 4 more Smart Citations

Heat Transfer Characteristics of Swirling Impinging Jets

Brown

Murray

Persoons

et al. 2009

Volume 9: Heat Transfer, Fluid Flows, and Thermal Systems, Parts A, B and C

View full text Add to dashboard Cite

Impinging jets are used in a wide number of industrial cooling applications due to their high heat and mass transfer abilities. The current research is concerned with the effect of swirl on the heat transfer characteristics of jet impingement cooling. Two inserts were designed order to generate swirling flow. These two designs, “Swirl Insert A” and “Swirl Insert B”, were tested at various Reynolds numbers, between 8000 and 16000 inclusive, and at H/D = 0.5 and 1. The jet was directed downwards onto a 25μm thick stainless steel foil which was ohmically heated. Images were recorded using a thermal imaging camera focused on the underside of the foil. These images were then analysed using Matlab and the Nusselt number profile was obtained. It was found that, while both swirl inserts establish an improvement in the heat transfer by comparison to that of a jet with no swirl, the “Swirl Insert B” design performed better that the “Swirl Insert A” design for high Reynolds number at H/D = 0.5 and consistently for H/D = 1. It was also discovered that, while both the “No Insert” and “Swirl Insert B” results did not change dramatically with an alteration in H/D, “Swirl Insert A” decreased by ∼10%.

show abstract

Section: Figure 58: Nusselt Number At R/d=0 For Swirlin^g Impinging supporting

confidence: 76%

Section: Onclud Ing R Em Arkssupporting

confidence: 53%

Section: Contoured Nozzle Geom Etry With Axial Vanesmentioning

confidence: 92%

Section: Im P In G In G J E T H E a T T R A N S F E Rmentioning

confidence: 98%

Section: Figure 224: Illustration O F Fluid (A) Suction and (B) Ejecmentioning

confidence: 99%

See 3 more Smart Citations

Heat Transfer Characteristics of Swirling Impinging Jets

Brown

Murray

Persoons

et al. 2009

Volume 9: Heat Transfer, Fluid Flows, and Thermal Systems, Parts A, B and C

View full text Add to dashboard Cite

show abstract

Coherent Structures in a Turbulent Swirling Jet Under Vortex Breakdown. 3D PIV Measurements

Алексеенко

Дулин

Tokarev

et al. 2016

Springer Proceedings in Physics

View full text Add to dashboard Cite

Phase-locked analysis of velocity fluctuations in a turbulent free swirling jet after vortex breakdown

2012

View full text Add to dashboard Cite

Large-scale organized vortical structures were studied experimentally in a free swirling jet of air experiencing vortex precession (PVC) at ambient conditions. Detailed measurements were performed in the region near the nozzle exit using phase-locked LDV and PIV, at a Reynolds number of Re ≈ 24,400 and a swirl parameter S ≈ 1.0. The investigation allowed reconstruction of the time-averaged flowfield, with the associated distribution of turbulent fluctuations, the phase-locked structure of the jet and the associated precessing vortex structure. An original joint analysis of power spectra and probability density functions of velocity data led to quantification of the PVC effect on turbulent fluctuations. This analysis showed that the PVC contribution can be properly separated from the background random turbulence, reproducing the results of phase-locked measurements. It is found that the background turbulence in the near field is substantially weaker if compared to the coherent fluctuations induced by vortex precession

show abstract

Effect of axisymmetric forcing on the structure of a swirling turbulent jet

Cited by 49 publications

References 32 publications

Heat Transfer Characteristics of Swirling Impinging Jets

Heat Transfer Characteristics of Swirling Impinging Jets

Coherent Structures in a Turbulent Swirling Jet Under Vortex Breakdown. 3D PIV Measurements

Phase-locked analysis of velocity fluctuations in a turbulent free swirling jet after vortex breakdown

Contact Info

Product

Resources

About