Experimental investigation on the flow induced vibration of an equilateral triangle prism in water |
| |
| Institution: | 1. MARINTEK, Trondheim, Norway;2. NTNU, Trondheim, Norway;3. Shell International Exploration and Production Inc., Houston, TX, USA;4. Statoil, Trondheim, Norway;1. Harbin Engineering University, Post-doctoral Fellow MRELab, University of Michigan, Ann Arbor, MI, USA;2. Marine Renewable Energy Laboratory, Dept. of Naval Architecture & Marine Engineering, University of Michigan, 2600 Draper Road, Ann Arbor, MI 48109-2145, USA;3. U.S. Department of Energy, Wind and Water Power Technologies Office, Golden Field Office, USA;4. Allegheny Science & Technology Contractor to US-DOE, USA;5. Department of Mechanical Engineering, University of Michigan, USA;6. Vortex Hydro Energy, Ann Arbor, MI, USA;1. School of Marine Science and Technology, Northwestern Polytechnical University, Xi’an, Shaanxi, China;2. College of Electromechanical Engineering, Qingdao University of Science and Technology, Qingdao 266061, Shandong, China;3. Department of Civil and Environmental Engineering, University of Houston, Houston, TX 77204, USA |
| |
| Abstract: | A series of flow induced vibration (FIV) experiments for an equilateral triangle prism elastically mounted in a water channel are performed with different system stiffness at constant damping and mass. An amplitude variation coefficient is proposed to describe FIV stationarity in the present study. The FIV of the prism can be divided into three primary regions based on the amplitude and frequency responses, which are the vortex induced vibration (VIV) branch, the transition branch from VIV to galloping, and the galloping branch. The transition branch occurs at the reduced velocity in the range of 7.8 < Ur = U/(fn,air·D) < 10.4, accompanied with a relatively rapid increase in amplitude and a precipitous drop in frequency and vibration stationarity. In addition, the reduced velocity where the transition region is initiated is independent of the system stiffness. The maximum amplitude reaches 3.17 D in the galloping branch. The ratio of the response frequency to the natural frequency of the prism in air remains locked to approximately 0.65 throughout the fully developed galloping branch. Large amplitude responses in an infinite range of flow velocities, excellent vibration stationarity and steady vibration frequencies, which are characteristics of the galloping of the prism, have a positive impact on improving energy conversion. |
| |
| Keywords: | Equilateral triangle prism Flow induced vibration Vortex induced vibration Transition branch from VIV to galloping Galloping |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
