DYNAMIC ANALYSIS FOR THE DESIGN OF C.A.L.M. SYSTEM IN SHALLOW AND DEEP WATERS
Yuh-Lin Hwang, IMODCO, Inc., Calabasas Hills, California
ABSTRACT
This paper presents a time domain analysis approach to evaluate the dynamic behavior of the Catenary Anchor Leg Mooring (CALM) system CALM system under the maximum operational condition when a tanker is moored to the terminal, and in the survival condition when the terminal is not occupied by a tanker. An analytical model, integrating tanker, hawser, buoy, and mooring lines is developed to dynamically predict the extreme mooring loads and buoy orbital motions, when responding to the effect of wind, current, wave frequency and wave drift response.
Numerical results describing the dynamic behaviors of the CALM system in both shallow and deep water situations are presented and discussed. The importance of the 1 i n e dynamics and hawser coupled buoy-tanker dynamics is demon strated by comparing the present dynamic analysis with catenary calculation approach. Results of the analysis arc compared with model test data to validate the mathematical model presented.
MOTION RESPONSE OF A MOORED BUOY IN WAVES
Chen Xiaohong and Huang Xianglu, State Key Laboratory of Ocean Engineering, Shanghai Jiao Tong University, P.R.C
Abstract
The motion responses of a moored buoy in both regular and irregular waves were analyzed in frequency domain by the perturbation method up to second order. The couple between the mooring line and buoy was considered in the analysis. For the second order motion, the second order forces induced by the mooring line were determined by a method proposed by authors. The coupling between the mooring line and buoy was determined b y the requirement of the continuity of the mooring line and buoy at the attach point. The problem was solved numerically. Examples of calculation results were given in the paper. Comparison between calculated results and model measurement is satisfactory.
