Translation control model and optimization method of immersed tube under action of water flow

Aiming at the translation control of immersed tube under the action of water flow, the resultant force and resultant moment of tugboats were analyzed based on the mathematical description, the calculation equations of tug moment in four quadrants were unified, the translation control model of immersed tube was built, and the number of working tugboats, the surplus capacity of towing force and the floating speed were considered.A weighted logarithmic ideal point particle swarm optimization (WLIPPSO) method was designed.Cramer's rule was utilized to handle constraints for towing forces and angles of towing forces.The simulation was carried out through tube floating control example of immersed tube tunnel in island tunnel project of Hong Kong-Zhuhai-Macao Bridge.Simulation result shows that when the total number of tugboats is six, in rising tide the floating speed is 4.770 kn, the fitness is 0.720, the number of working tugboats is three, and the surplus capacity product of towing force is 2.693×10²⁰ kN⁶.In falling tide the floating speed is 1.750 kn, the fitness is 3.042, the number of working tugboats is five, and the surplus capacity product of towing force is 3.352×10¹⁹ kN⁶.So the model and method proposed have strong applicability, the fitness is better, the number of working tugboats is smaller, surplus capacity of towing force and floating speed are higher.