Design Of Marine Diesel Engine Lubricating Oil Temperature Monitoring System

Due to the immaturity of new energy ship technology,there are problems such as cost and practicality,and diesel engines are still the main source of power for ships.As one of the main means of transportation,its particulate emissions account for a large proportion of total mobile source particulate matter emissions,with the continuous improvement of global environmental awareness and the promotion of policies and regulations,the energy conservation and emission reduction of ships has become a hot topic in China and even the global shipping industry.Ship diesel engines are inseparable from lubricating oil in normal operation,but when the temperature of lubricating oil is too high,its viscosity will be reduced,and it is easier to enter the combustion chamber,resulting in a large number of particulate emissions;When the lubricating oil temperature is too low,the viscosity will increase,which will adversely affect the delivery and circulation of lubricating oil.Therefore,keeping the lubricating oil temperature stable in the appropriate range is very important to reduce particulate emissions from marine diesel engines.Based on the analysis of the heat transfer theory of lubricating oil,this thesis builds a model of diesel engine lubricating oil tank and pipeline system,and realizes real-time monitoring and control of lubricating oil temperature without network through the designed lubricating oil monitoring system,which provides a new idea for realizing energy saving and emission reduction of ships.Firstly,the modeling and simulation of the lubricating oil tank and oil pipeline model was carried out by AMESim software,and the lubricating oil temperature change curve at different speeds of the simulated prime mover was introduced into MATLAB for system identification and conversion into transfer function,and at the same time the lubricating oil temperature control system was built in Simulink,and the lubricating oil temperature was adjusted by PID control and fuzzy PID control to reach and stabilize at the preset temperature.In terms of controller,this thesis selects programmable logic controller(PLC)for control and redundant design to improve the reliability of the system.Finally,through program design,creating a human-machine interface(HMI)interface and writing a web control program,this thesis realizes the HMI monitoring of PID control and fuzzy PID control free switching and the function of monitoring the lubricating oil temperature by mobile phone APP,which ensures real-time monitoring of lubricating oil temperature within the signal range of the router in the absence of a network.