Analysis of the vortex core and turbulence structure behind axial fans in a straight pipe using PIV, LDA and HWA methods

Čantrak, S.

doi:10.2298/bg20120730cantrak

Cited by 5 publications

(21 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For these computations a high quality block-structured grid was generated, and taking into account the geometry of the fan, k-omega SST and SST-SAS models were used. These computations were verified using experimental results [125]. Additionally, using the same numerical grid, computations with LES and dynamic Smagorinsky model were also performed in SPARC, an in-house code from the KIT IFM.…”

Section: S903mentioning

confidence: 93%

“…In the vortex core Čantrak Dj. introduced stereo particle image velocimetry (SPIV) in his research in 2007 [106,108,114,118,119,121,122,125,126,127,128,132,133,139,141,146,147,150]. He investigated the structure of turbulent swirl flow generated by the axial fan impellers in the pipe.…”

Section: Turbulence Statisticsmentioning

confidence: 99%

“…Numerous experiments were carried out in the modified existing test rig at the FME UB and in the entire newly built experimental test rig in Karlsruhe Institute of Technology, Institute of Fluid Machinery (KIT IFM). Turbulent stresses were determined on the basis of the HSS PIV measurements what enabled the formation of anisotropy invariant maps for various fan blade angles for the first time in the scientific literature [125,141].…”

Section: Turbulence Statisticsmentioning

confidence: 99%

See 2 more Smart Citations

The school of the turbulent swirling flow at the Faculty of Mechanical Engineering University of Belgrade

et al. 2017

Self Cite

View full text Add to dashboard Cite

hydraulic turbines to be continued by the experimental and analytical approaches on the axial fans pressure side. The complexity of 3-D, non-homogeneous, anisotropic turbulent velocity fields required complex experimental and theoretical approach, associated with the complex numerical procedures. Analytical approaches, complex statistical analyses and experimental methods and afterwards CFD employed in the research are presented in this paper. The 150 scientific papers, numerous diploma works, several master of science (magister) theses, six Ph. D. theses and two in progress, 40 researchers, national and international projects are the facts about the School. Scientific references are chronologically presented. Numerous abstracts from scientific conferences, presentations, projects with industry and lectures are not given here.Many researchers of the School of the turbulent swirling flow at the Faculty of Mechanical Engineering, University of Belgrade (FME UB) carried on and contributed to the research of the turbulent swirling flows . Vušković (1912Vušković ( -2005 published his first paper [1] in 1941, where he studied the problem of generation and stability of the vortex core in turbomachines, specifically behind the hydraulic turbine runners. Vušković continued his research and afterwards published paper [2], and Vušković and Velenšek [4].Obradović [3] discussed vortex hydrodynamic stability with constant circulation in the cylindrical pipes.Determination of the dead water diameter behind the axial fan without guide vanes was done by Protić [5]. Also, he was the first to introduce the idea of investigating the turbulent swirling flow behind the axial fan in the pipe. Further investigations are conducted at the Chair for hydraulic machinery and energy systems and at the Chair for fluid mechanics FME UB.Experimental investigations of the turbulent swirling flow in the long lined straight pipes behind the axial fan without guide vanes started at the FME UB in 1972, when experimental test rig was built and measurement equipment was designed by Benišek. First results from this test rig were published in [6,7,9,13]. Čantrak S. [19] was the first to commence investigations of turbulence at the FME UB and implemented turbulence statistics in the turbulent swirling flow.These investigations are ongoing getting deeper into the turbulent swirling flow phenomenology. The defended theses and published papers are part of this review and are listed in references. Chronologically are presented almost all scientific papers, a number of master of science (magister) theses and six Ph. D. theses that belong to the School. Two Ph. D. theses in this field are in progress. Numerous diploma works were defended at the Chair for hydraulic machinery and energy systems and at the Chair for fluid mechanics FME UB in this field. Forty researchers from Serbia, and from abroad as well, are members of this School. National and international projects, numerous abstracts from scientific conferences, presentations, projects for industry and le...

show abstract

Section: S903mentioning

confidence: 93%

Section: Turbulence Statisticsmentioning

confidence: 99%

Section: Turbulence Statisticsmentioning

confidence: 99%

See 1 more Smart Citation

The school of the turbulent swirling flow at the Faculty of Mechanical Engineering University of Belgrade

et al. 2017

Self Cite

View full text Add to dashboard Cite

show abstract

“…The incompressible swirl flow field is generated by the axial fan impeller (2) with a rotational speed-contolled motor (1) ( Figure 1). The main geometry characteristics of the axial fan impeller, model AP 400, Minel, Serbia, are provided in [6,9]. The fan impeller has seven blades adjusted at the angle of 29 • at the outer diameter.…”

Section: Figure 1 Test Rig For Experimental Investigationsmentioning

confidence: 99%

“…Statistical properties of the turbulent swirl flow in diffusers are studied in [3,4]. The influence of the Reynolds number on integral and statistical properties of the generated turbulent swirl flow is studied in [5,6]. The results of experimental investigations of the turbulent swirl flow in three straight conical diffusers with various diffuser total angles (8.6 • , 10.5 • and 12.6 • ) are presented in [7,8].…”

Section: Introductionmentioning

confidence: 99%

Integral and statistical characteristics of the turbulent swirl flow in a straight conical diffuser

Ilić¹,

Čantrak²,

Janković³

2018

Theor appl mech (Belgr)

Self Cite

View full text Add to dashboard Cite

The results of the experimental investigations of the turbulent swirl flow in a straight conical diffuser with inlet diameter 0.4 m and total divergence angle 8.6 • are presented in this paper. The incompressible swirl flow field is generated by the axial fan with outer diameter 0.397 m. The measurements were performed in one measuring section downstream the axial fan impeller in the conical diffuser in position (z/R 0 = 1) with original classical probes and an one-component laser Doppler anemometry (LDA) system, for four flow regimes. The comparative measurements of axial and circumferential velocities are presented. The Reynolds number, calculated on the basis of the average velocity, ranges from 149857 to 216916. Integral parameters, such as volume flow rate, average circulation and swirl number, are determined. Statistical characteristics, such as level of turbulence, skewness and flatness factors, are calculated. The highest levels of turbulence for axial velocity are reached in region 0.4 < r/R < 0.6, where D = 2R. The highest levels of turbulence for circumferential velocity are reached for the regimes with lower circulation in r/R ≈ 0.4, i.e., in the vortex core region for the cases with higher circulation.

show abstract

Turbulence investigation of the NASA common research model wing tip vortex

Čantrak¹,

Heineck

Kushner³

et al. 2017

Therm sci

Self Cite

View full text Add to dashboard Cite

The paper presents high-speed stereo particle image velocimetry investigation of the NASA Common Research Model wing tip vortex. A three-percent scaled semi-span model, without nacelle and pylon, was tested in the 32-by 48-inch Indraft tunnel, at the Fluid Mechanics Laboratory at the NASA Ames Research Center. Turbulence investigation of the wing tip vortex is presented. Measurements of the wing-tip vortex were performed in a vertical cross-stream plane three tip-chords downstream of the wing tip trailing edge with a 2 kHz sampling rate. Experimental data are analyzed in the invariant anisotropy maps for three various angles of attack (0°, 2°, and 4°) and the same speed generated in the tunnel (V ∞ = 50 m/s). This corresponds to a chord Reynolds number 2.6810 5 , where the chord length of 3" is considered the characteristic length. The region of interest was x = 220 mm and y = 90 mm. The 20 000 particle image velocimetry samples were acquired at each condition. Velocity fields and turbulence statistics are given for all cases, as well as turbulence structure in the light of the invariant theory. Prediction of the wing tip vortices is still a challenge for the computational fluid dynamics codes due to significant pressure and velocity gradients.

show abstract

Analysis of the vortex core and turbulence structure behind axial fans in a straight pipe using PIV, LDA and HWA methods

Cited by 5 publications

References 15 publications

The school of the turbulent swirling flow at the Faculty of Mechanical Engineering University of Belgrade

The school of the turbulent swirling flow at the Faculty of Mechanical Engineering University of Belgrade

Integral and statistical characteristics of the turbulent swirl flow in a straight conical diffuser

Turbulence investigation of the NASA common research model wing tip vortex

Contact Info

Product

Resources

About