Simulation Research On Hydraulic System Of Marine Steering Gear

Marine steering gear is used as the control equipment of ship course, and the quality of its performance is significantly affecting the safety of ship. Hydraulic system of marine steering gear is widely used on ship. The performance test of traditional marine steering gear is taken place before the first sail or after the ship repair in dock, and it is high-cost and long-cycle. In this paper, the entity of hydraulic system of the marine steering gear in the laboratory of our institute is the object for the simulation model of the mechanics-hydraulics. Applying simulation technique to the process of testing research on the hydraulic system of marine steering gear not only reduces the cost of the performance test, but also can predict and optimize the test scheme. The study for the simulation of the complex system is of great significance.Combination of mechanics-electrics-hydraulics integration and computer technology for the simulation of the hydraulic system is the development trend of the hydraulic technology. The EASY5 and ADAMS simulation software can be used on the co-simulation study of the marine steering gear. The co-simulation can combine the character of the hydraulic system and mechanical system of marine steering gear, and through the data interactive transmission real time, the dynamic simulation of the motivation and movement of the system come true immediately, and the error rate is small compared to the test, so can intuitively predict the performance of marine steering gear. The main research work carried out as follows:1 Based on deeply understanding of the composition and function of hydraulic system of the marine steering gear, the simulation modules of the hydraulic and the mechanical components are constructed respectively in EASY5 and ADAMS simulation software, and the basic function can be actualized through setting the parameters of the module.In EASY5, the function of combination of variable volume pump and 4-way valve is used for two-way variable pump model, and a one-haulm dual-action hydraulic jar is used for the marine steering gear turning cylinder, and used the control on the components, all of these turn out the function of the hydraulic system of the marine steering gear. The actual dimension of the marine steering gear is constituted in the CAXA software, and the data of the 3D-model is exported to ADAMS software for setting up the entity structure simulation model of marine steering gear.2 Combined the actual performance of marine steering gear and the respective simulation advantages of simulation software EASY5 and ADAMS, the co-simulation is successfully constituted and the data of the hydraulic and the mechanical in the simulation can be transmitted to and from each other synchronously, and the organic links come true that the link of kinematics-dynamics between the fluid power and mechanical components.3 After finishing the co-simulation of the hydraulic system of marine steering gear, the difference between the performance of the marine steering gear in the actual test and the result of the co-simulation was compared and analyzed, and the results out of the two was found in coincide with each other. In other words, the co-simulation is correct.The parameters, such as the speed and the displacement volume per revolution of the pump, the unlock pressure of the safety valve, set in the co-simulation model are measured through doing the empty and load test of the marine steering gear. And the force function acted on the cylinder is transferred from the pressure on the load cylinder of the marine steering gear in test. At last, analyzing the different results between the test and the simulation is using for the truth testimony of the co-simulation model.In summary, this paper sets up a co-simulation model of mechanism and hydraulic of the marine steering gear, and this model has been validated with the actual physics test. This co-simulation method is a new research approach for the simulation on the performance of hydraulic system of marine steering gear using computer, it can also extend to the simulation on other engineering hydraulic systems.