Parameter identification of nonlinear roll motion equation for floating structures in irregular waves |
| |
| Institution: | 1. School of Naval Architecture, Ocean and Civil Engineering, Shanghai Jiao Tong University, Shanghai 200240, China;2. State Key Laboratory of Ocean Engineering, Shanghai Jiao Tong University, Shanghai 200240, China;1. Maritime College, Guangdong Ocean University, Zhanjiang, 524088, Guangdong, China;2. Division of Navigation Science, Mokpo Maritime University, 58628, South Korea |
| |
| Abstract: | In order to predict the roll motion of a floating structure in irregular waves accurately, it is crucial to estimate the unknown damping coefficients and restoring moment coefficients in the nonlinear roll motion equation. In this paper, a parameter identification method based on a combination of random decrement technique and support vector regression (SVR) is proposed to identify the coefficients in the roll motion equation of a floating structure by using the measured roll response in irregular waves. Case studies based on the simulation data and model test data respectively are designed to validate the applicability and validity of the identification method. Firstly, the roll motion of a vessel is simulated by using the known coefficients from literature, and the simulated data are used to identify the coefficients in the roll motion equation. The identified coefficients are compared with the known values to validate the applicability of the identification method. Then the roll motion is predicted by using the identified coefficients. The prediction results are compared with the simulated data, and good agreement is achieved. Secondly, the model test data of a FPSO are used to identify the coefficients in the roll motion equation. Then the random decrement signature of the roll motion is predicted by using the identified coefficients and compared with that obtained from the model test data, and satisfactory agreement is achieved. From this study, it is shown that the identification method can be effectively applied to identify the coefficients in the nonlinear roll motion equation in irregular waves. |
| |
| Keywords: | Nonlinear roll motion Floating structure Random decrement technique Support vector regression Parameter identification |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
