- Author
- Simiu, E. | Cook, G. R. | Alibe, B.
- Title
- Chaotic Motions of Coupled Galloping Oscillators and Their Modeling as Diffusion Processes.
- Coporate
- National Institute of Standards and Technology, Gaithersburg, MD Morgan State Univ., Baltimore, MD
- Book or Conf
- CERRA, International Association for Civil Engineering Reliability and Risk Analysis. Applications of Statistics and Probability in Civil Engineering, 6th International Conference. CERRA-ICASP 6. 1991, Mexico City, Mexico, Esteva, L.; Ruiz, S. E., Editors, 993-1000 p., 1991
- Keywords
- oscillators | chaotic motions | diffusion processes | failure | equations | numerical analysis | tests
- Abstract
- According to numerical investigations recently reported in the literature, certain types of compliant offshore structures may experience undesirable hydroelastic responses, including chaotic responses. The question arises whether such responses can be predicted reliably by using current fluidelastic models. We addressed this question in the specific case of a paradigmatic, strongly nonlinear hydroelastic oscillator consisting of two elastically restrained and coupled square prisms immersed in a uniform flow. Experiments showed that beyond a critical flow velocity the oscillator exhibits strongly chaotic behavior. Extensive numerical simulations suggest that by using conventional fluidelastic models the observed chaotic motions can be described qualitatively, at lease in certain instances; however, the windows of deterministic chaos, if they exist, are quite narrow, so that those motions cannot in general be predicted reliably. It is then shown that modeling the hydroelastic system as a nonlinear diffusion process helps to improve substantially the reliability of the predictions.