8V280 Kinematics And Dynamics Diagnosis Analysis Of Diesel Crank Connecting Rod Mechanism

With the further "heavy load and speed" of railroad transportation,the reliability and safety of diesel engines of internal combustion locomotives have put forward higher requirements.As one of the most important parts of the diesel engine,the crank connecting rod mechanism often works under high temperature and high pressure and other harsh environments,so it is easy to produce yielding,fatigue and other problems,which can seriously damage the whole engine system.Therefore,it is important to improve the parameters of the crank linkage mechanism to improve the efficiency and service life of the diesel engine,and then improve its performance.Firstly,the kinematic and kinetic theories are applied to analyze the motion process of the diesel engine crank connecting rod mechanism in detail,and the theoretical equations of displacement,velocity and acceleration of the piston and connecting rod are derived to better understand the motion process of the crank connecting rod mechanism.In addition,the theoretical derivation of the gas force and its own inertia force on the crank connecting rod mechanism and its theoretical calculation equations are derived to provide a theoretical basis for the subsequent simulation analysis.Then the crank linkage mechanism of the 8V280 diesel engine was used as the research object,and the virtual prototype model of the crank linkage mechanism of the 8V280 diesel engine was built by applying the GT-CRANK section of the GT-SUITE software for the first time to study the kinematics and dynamics characteristics of the diesel engine crank linkage mechanism.The kinematic and dynamics parameters of the crank linkage mechanism were analyzed to evaluate the crank linkage trajectory,energy consumption and stability.Based on the analysis of the kinematic and dynamics simulation results,the parameters of the crank linkage mechanism that need to be improved are identified.Finally,by varying the ignition sequence,connecting rod ratio,piston mass,piston pin offset,bearing clearance,lubricating oil temperature and main journal diameter of the diesel engine crank connecting rod mechanism,the dynamics simulation of the virtual prototype model of the crank connecting rod mechanism was carried out to study the effects of the above parameters on the balanced performance of the diesel engine,the final analysis of the simulation results obtained with different parameter variables shows that the diesel engine achieves a better balance performance when the ignition sequence is 1-5-7-3-8-4-2-6,the connecting rod ratio is 0.246,the piston mass is 32 kg,the piston pin offset is 0.06 mm,the bearing clearance is 0.22 mm,the lubricating oil temperature is 75°C,and the main journal diameter is 240 mm.state.The above parameters will provide reference for the subsequent improvement and design of the diesel engine,and provide a test basis for the actual engine test of the manufacturer.