Research On Fpr Yacht Which Hull Integrated With Oil And Water Tank

The oil and water tank structure of fiberglass yacht are important part of the yacht.With the appearance of composite material used in building oil and water tank,a new design method integrating the oil and water tank structure with the yacht hull can be a good solution to a series of exposed problems in the oil and water tank which built by traditional metal materials,such as low space utilization,significant pitch changes under different loads and fuel leakage.Meanwhile,this design method also imposes higher requirements on the structural strength and other safety performance of the yacht.In this paper,a 78 ft super yacht which integrating the oil and water tank structure with the yacht hull is designed for structural strength analysis and parameter optimization to improve the safety performance of the yacht.The main contents as follows:1)Building a yacht model which integrated oil and water tank structure with the yacht hull,as well according to the force characteristics of the yacht sailing in the water to predict the wave load of the yacht.According to the results of wave load calculation and the entire structure of the yacht to finite element analysis.Based on the Tsai-Wu's failure criterion to check the strength of its critical parts and determine the failure of the structure.After calculation,the stress concentration area appears at the rear of the yacht hull and the maximum stress value is49.05 Mpa,the result in line with actual damage.2)Based on the strength analysis of the finite element structure,with the lightest weight as the optimization goal and the layer thickness of each layer of the composite material as design variable,establishing the approximation of RSM between the design variable and the analysis target.The Response Surface Methodology is used to calculate and screen the calculated samples,and to find the design scheme which makes the total weight of the yacht lightest in the case of meeting the strength requirements.After calculation,the overall quality of the yacht decreased by 1.6%,achieving the goal of lightweight design.3)Based on the result of lightweight design,according to the mechanical characteristics of composite materials and combining the particularity of oil and water tank structure to construct a parameter model of the oil and water tank structure,as well to determine the appropriate function of the genetic algorithm and optimize the layer of the oil and water tank structure.It strengthensthe structure of oil and water tank structure.Research results show that the minimum cut of stress value of yacht hull achieving 9%.4)Study the initial stability of yachts which integrated oil and water tank structure with the yacht hull under loading conditions of full load departure,male child on the way and racing to the port,and establish a location optimization mathematical model of oil and water tank structure based on the oil and water tank layout design criteria.The minimum balance moment is the optimization goal.The particle swarm optimization is used to optimize the position of the oil and water tank,the stability of the yacht are calculated at different positions,and the stability curve is plotted.The influence of position arrangement on the stability is analyzed.Research results show that in three kinds of load conditions,the average increase of high initial stability of the yacht achieving 6%,the maximum righting arm have been improved 11.6%,13.5%,16.6%.