Buy article PDF
Instant access to
the full article PDF
for the next 48 hrs
US$ 35
|
Wind and Structures Volume 30, Number 6, June 2020 , pages 617-631 DOI: https://doi.org/10.12989/was.2020.30.6.617 |
|
|
|
Wind tunnel study of wake-induced aerodynamics of parallel stay-cables and power conductor cables in a yawed flow |
||
Mohammad Jafari and Partha P. Sarkar
|
||
| Abstract | ||
| Wake-induced aerodynamics of yawed circular cylinders with smooth and grooved surfaces in a tandem arrangement was studied. This pair of cylinders represent sections of stay-cables with smooth surfaces and high-voltage power conductors with grooved surfaces that are vulnerable to flow-induced structural failure. The study provides some insight for a better understanding of wake-induced loads and galloping problem of bundled cables. All experiments in this study were conducted using a pair of stationary section models of circular cylinders in a wind tunnel subjected to uniform and smooth flow. The aerodynamic force coefficients and vortex-shedding frequency of the downstream model were extracted from the surface pressure distribution. For measurement, polished aluminum tubes were used as smooth cables; and hollow tubes with a helically grooved surface were used as power conductors. The aerodynamic properties of the downstream model were captured at wind speeds of about 6-23 m/s (Reynolds number of 5 x 104 to 2.67 x 105 for smooth cable and 2 x 104 to 1.01 x 105 for grooved cable) and yaw angles ranging from 0 to 45 while the upstream model was fixed at the various spacing between the two model cylinders. The results showed that the Strouhal number of yawed cable is less than the non-yawed case at a given Reynolds number, and its value is smaller than the Strouhal number of a single cable. Additionally, compared to the single smooth cable, it was observed that there was a reduction of drag coefficient of the downstream model, but no change in a drag coefficient of the downstream grooved case in the range of Reynolds number in this study. | ||
| Key Words | ||
| tandem arrangement; smooth cylinders; grooved cylinders; yawed cable; bundled cables; power conductors | ||
| Address | ||
| Mohammad Jafari and Partha P. Sarkar:Department of Aerospace Engineering, Iowa State University, Ames, IA 50011, USA | ||