Wind and Structures
Volume 23, Number 2, 2016, pages 143-155
DOI: 10.12989/was.2016.23.2.143
Aerodynamics of a cylinder in the wake of a V-shaped object
Sangil Kim, Md. Mahbub Alam and Mohammad Russel
Abstract
The interaction between two different shaped structures is very important to be understood. Fluid-structure interactions and aerodynamics of a circular cylinder in the wake of a V-shaped cylinder are examined experimentally, including forces, shedding frequencies, lock-in process, etc., with the V-shaped cylinder width d varying from d/D = 0.6 to 2, where D is the circular cylinder diameter. While the streamwise separation between the circular cylinder and V-shaped cylinder was 10D fixed, the transverse distance T between them was varied from T/D = 0 to 1.5. While fluid force and shedding frequency of the circular cylinder were measured using a load cell installed in the circular cylinder, measurement of shedding frequency of the V-shaped cylinder was done by a hotwire. The major findings are: (i) a larger d begets a larger velocity deficit in the wake; (ii) with increase in d/D, the lock-in between the shedding from the two cylinders is centered at d/D = 1.1, occurring at d/D 0.95-1.35 depending on T/D; (iii) at a given T/D, when d/D is increased, the fluctuating lift grows and reaches a maximum before decaying; the d/D corresponding to the maximum fluctuating lift is dependent on T/D, and the relationship between them is linear, expressed as ; that is, a larger d/D corresponds to a greater T/D for the maximum fluctuating lift.
Key Words
cylinder; lock-in; wake; fluctuating lift force
Address
Sangil Kim: Department of Mechanical Engineering, Kangwon National University, 346 Jungang-ro, Samcheok 25913, Republic of Korea
Md. Mahbub Alam: Institute for Turbulence-Noise-Vibration Interaction and Control, Shenzhen Graduate School,
Harbin Institute of Technology, Shenzhen 518055, China;
Digital Engineering Laboratory of Offshore Equipment, Shenzhen, China
Mohammad Russel: School of Food and Environment, Key laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, Dalian University of Technology, Panjin 124221, China