Nanoparticle-laden gas flow around a circular cylinder at high Reynolds number

Abstract

Purpose

Experiments to investigate the characteristic distribution of nanoparticle-laden gas flow around a circular cylinder were performed with a fast mobility particle spectrometer. The paper aims to discuss these issues.

Design/methodology/approach

The fast mobility particle sizer spectrometer is used to measure quasi-instantaneous particle number density. The acquired particle number density, total concentration, and geometric mean diameter at free stream and in the wake were used to discuss the particle characteristic distribution. The time-averaged velocity field detected by particle imaging velocimetry was used to investigate the effect of carried phase on nanoparticles distribution.

Findings

Results show that the total particle concentration in the free stream is larger than that in the wake. However, the geometric mean diameter of particle in the free stream is smaller than that in the wake for different Re. The total particle concentration and geometric mean diameter in the free stream and the wake both change in the same way, but with an obvious lag which increases with Re. Despite particle deposition, the number density of particles with electrical-mobility-equivalent diameters in the range from 220.7 to 523.3 nm in the wake is still higher than that in the free stream.

Originality/value

Though the particles-laden gas flow around a circular cylinder had been studied experimentally and numerically before, where particles are larger than one micrometer, investigators paid little attention on the nanoparticles-laden gas flow where particles are smaller than one micrometer, especially at high Reynolds number, because numerical methods so far cannot deal these problems completely and satisfactorily. However, this issue is widely existing in nature and engineering application, such as superfine dust or microorganism captured by a circular cylinder model.

Citation

Tu, C. and Zhang, J. (2014), "Nanoparticle-laden gas flow around a circular cylinder at high Reynolds number", International Journal of Numerical Methods for Heat & Fluid Flow, Vol. 24 No. 8, pp. 1782-1794. https://doi.org/10.1108/HFF-03-2013-0101