Effect of particle polydispersity on particle concentration measurement by using laser Doppler anemometry

Ayranci, Isil
Pinguet, Guillaume
Escudie, Dany
Selçuk, Nevin
Vaillon, Rodolphe
Andre, Frederic
Measurement of particle concentration by laser Doppler anemometry (LDA) is studied on a vertical air jet seeded by a powder disperser with controlled particle and air flow rates. Particle arrival rate is utilized to retrieve particle number densities from conventional LDA operation. The effect of polydisperse nature of the particles is assessed. Comparisons between measured and estimated particle number densities suggest that only a certain portion of the particle population with a particle size to fringe spacing ratio around unity can be detected. Results indicate that reliable measurement of absolute particle concentration is possible for a particle population of narrow size distribution with an average diameter equivalent to fringe spacing. Present number density measurement technique which is useful for practical purposes with conventional LDA systems is found to yield physically reasonable profiles in both laminar and turbulent regimes. (c) 2006 Elsevier Inc. All rights reserved.


Effect of Sn Alloying on the Diffusion Bonding Behavior of Al-Mg-Si Alloys
Atabay, SILA ECE; Esen, Ziya; Dericioğlu, Arcan Fehmi (2017-07-01)
Effect of Sn as an alloying element on the diffusion-bonding behavior of Al-Mg-Si alloy has been studied by means of differential scanning calorimetry (DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM) and mechanical testing of the diffusion-bonded joint. XRD results revealed the formation of Mg2Sn and (Sn) phases during solidification following induction casting. DSC results showed local liquid (Sn) formation during the bonding process for Sn-containing alloys, where its amount was found to...
Effect of Passive Bleeding on Flow Structure over a Nonslender Delta Wing
Celik, Alper; Cetin, Cenk; Yavuz, Mehmet Metin (2017-08-01)
The effect of passive bleeding on flow structure of a 45 deg swept delta wing is studied in a low-speed wind tunnel using techniques of laser-illuminated smoke visualization, surface-pressure measurements, and particle image velocimetry. Three different bleeding configurations are tested to identify the effectiveness of the control technique compared to a base planform for a broad range of attack angles 6 <= alpha <= 6deg at Reynolds numbers Re=3.5x10(4) and Re=10(5). The results indicate that all bleeding ...
Effect of grain boundary microcracking on the light transmittance of sintered transparent MgAl2O4
Dericioğlu, Arcan Fehmi (2003-05-01)
Optically transparent polycrystalline magnesium aluminate spinel (MgAl2O4) has been fabricated by hot-pressing followed by hot isostatic pressing (HIPing). The effect of microstructure on the light transmittance of the sintered MgAl2O4 is discussed. The sintered MgAl2O4 with a thickness of 2 mm has a maximum light transmittance of similar to60 and similar to70% in the UV-visible and near-IR wavelength regions, respectively, although it contains microcracking along its grain boundaries. Light transmittance l...
Effect of thickness-to-chord ratio on aerodynamics of non-slender delta wing
Ghazijahani, Mohammad Sharifi; Yavuz, Mehmet Metin (2019-05-01)
The effect of thickness-to-chord (t/C) ratio on aerodynamics of a non-slender delta wing with sweep angle of 45 degree is characterized in a low-speed wind tunnel using laser illuminated smoke visualization, surface pressure measurements, particle image velocimetry, and force measurements. The delta wings of t/C ratios varying from 2% to 15% with 45 degree windward beveled leading edges are tested. The results indicate that the effect of t/C ratio on flow structure is quite substantial. Considering the low ...
Effect of chemical composition on the optical properties and fracture toughness of transparent magnesium aluminate spinel ceramics
Dericioğlu, Arcan Fehmi; Dlouhy, Ivo; Kagawa, Yutaka (2005-05-01)
Polycrystalline transparent magnesium aluminate "spinel" ceramics were fabricated by hot-pressing and hot isostatic pressing (HIPing) using commercially available MgO and Al2O3 Powders. Al2O3 content of spinet was systematically changed that can be expressed as MgO.nAl(2)O(3) with n = 1.0, 1.5 and 2.0. UV/visible and near-IR wavelength region light reflection and transmission behaviors of the spinet ceramics were quantitatively correlated to their microstructure to account for the optical quality of the fab...
Citation Formats
I. Ayranci, G. Pinguet, D. Escudie, N. Selçuk, R. Vaillon, and F. Andre, “Effect of particle polydispersity on particle concentration measurement by using laser Doppler anemometry,” EXPERIMENTAL THERMAL AND FLUID SCIENCE, pp. 839–847, 2007, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/30023.