Frequency measurements in a finite cylinder wake at a subcritical Reynolds number

Abstract

A spectral study of a hot-wire investigation in the near wake of a finite circular cylinder of high-aspect ratio is reported. The measurements included frequency spectra and cross correlations in span wise and stream wise directions. The study identifies four spanwise regions, in terms of frequency, in the immediate wake of the finite cylinder.Nomenclature D = diameter of circular cylinder d f = wake width at end of formation region / = frequency of vortex shedding / = length of circular cylinder l f = formation length R xy (T) = cross-correlation function UQ = freestream speed x = streamwise coordinate (see Fig. 1) y = crosswise coordinate perpendicular to span of cylinder (see Fig. 1) z = spanwise coordinate (see Fig. 1) T = time

A review of flow-induced noise from finite wall-mounted cylinders

“…This is attributed to differences in incoming boundary layer thickness and experimental conditions. Cellular variation in wake frequency was also found by Gerich and Eckelmann (1982), Budair et al (1991), and Kitagawa et al (2002). Gerich and Eckelmann (1982) and Lee (1997) measured a beat frequency due to two shedding frequencies in different cells which further supports the cellular nature of the wake.…”

“…Flow around the cylinder sides enters into a regular alternating von Kármán vortex street. The pressure difference between the lee side of the FWMC and the oncoming free stream induces downwash (downward motion of the separated shear layer Baker (1980) 1980Farivar (1981 1981 Ayoub and Karamcheti (1982) 1982 Sakamoto and Arie (1983) 1983 Kawamura et al (1984) 1984 Sakamoto and Oiwake (1984) 1984 Budair et al (1991) 1991 Baban and So (1991) 1991 Okamoto and Sunabashiri (1992) 1992 Agui and Andreopoulos (1992) 1992 Szepessy and Bearman (1992) 1992 West (1993a, 1993b) 1993 Fox and Apelt (1993) 1993 Tanaka and Murata (1999) 1999 Kitagawa et al (1999) 1999 Park and Lee (2000) 2000 Park and Lee (2002) 2002 Roh and Park (2003) 2003 Leder (2003) 2003 Sumner et al (2004) 2004 Wang et al (2004) 2004 Pattenden et al (2005) 2005 Wang et al (2006) 2006 Adaramola et al (2006) 2006 Hain et al (2008) 2008 Becker et al (2008) 2008 Wang and Zhou (2009) 2009 Bourgeois et al (2011) 2011Hajimirzaie et al (2012 2012 Iungo et al (2012) 2012 Sattari et al (2012) 2012 Moreau and Doolan (2013) 2013 Hosseini et al (2013) 2013 Rostamy et al (2013) 2013 Uffinger et al (2013) 2013 a Sq. is the square cross section.…”

Experimental investigation on the aerodynamic loads and wake flow features of a low aspect-ratio circular cylinder

“…St ¼0.145 in Sakamoto and Arie (1983). Moreover, other authors like Farivar (1981), Okamoto and Yagita (1973), Budair et al (1991), Okamoto and Sunabashiri (1992), Fröhlich and Rodi (2004) did not found a dominant spectral contribution related to vortex shedding. This evident disagreement between the results of different experimental works is probably due to the different values of the boundary layer thickness as percentage of the model height and of the freestream turbulence level.…”