DETERMINATION OF A MAN B&W 8L48/60 MARINE ENGINE WORKFLOW DISRUPTION INFLUENCE ON THE DYNAMIC INDICATORS OF THE CRANK MECHANISM
Abstract
Introduction. The application of torsional oscillation analysis of dynamic models of internal combustion engines for the diagnostic complexes development and improvement is evaluated. Reducing the operating costs of modern marine medium-speed engines (MSE), associated with the cost of maintenance and repair, and is possible by equipping ship power plants with systems for continuous monitoring of the workflow efficiency in engine cylinders. The complexity of the diesel engine dynamic system and the stochastic nature of malfunctions occurrence requires a detailed study of the impact of engine systems and mechanisms technical condition changes on the indicators of torsional oscillations. One of the effective means of such research is computer modeling using specialized software packages. Purpose. A description of the objects of the dynamic processes research module of internal combustion engines mechanical systems, used to simulate torsional oscillations in the GT-SUITE software package, is presented. A description of a computer 1-D model of the MAN 8L48/60 marine diesel engine and the features of setting up the main templates for modeling the dynamic processes of a serviceable engine and an engine with a disruption of the 5th cylinder workflow are presented. Results. Comparison of the simulation results indicates that the difference in flywheel angular accelerations is 3033 rad/s2, and at the free end is 20652 rad/s2 for the nominal load mode. The effect of elements harmonic oscillations on the value of the crankshaft angular accelerations is established. Conclusions. It has been established that the main influence is exerted by fourth-order harmonic oscillations, exceeding the others by 6 or more times.
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References
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