Development Of Test Data Management System And Performance Simulation For Marine Diesel Engine

With the high speed development of the shipping career and the more rigorous emission control regulations, various performance of diesel engine must be accordingly optimized to satisfy the needs. But the optimization of diesel engine needs a certain amount of tests and experimental datas. What's more, commissioning not only needs simulation analysis, but also causes a great amount of complex test datas. So the paper deeply analysed these demands, simulated thermal performance and emission performance of the diesel engine6L21/31which would offer a guidance for testing and the optimization of the diesel engine, and developed the diesel engine test data management and performance analysis software. In addition, the software satisfied the demands of accessing test data and analyzing performance. The paper mainly researched as follows:1) The diesel engine test data management system was designed based on analyzing the demands of users. The paper briefly introduced the design process of the software frame from the view of the multilayer distributed structure, the client plugin structure and the function realization. The overall design of the multithreading progress bar was confirmed, and on its basis, the design scheme and the implementation details of several key technology points such as accessing a great amount of test datas and progress bar were analyzed.2) The design ideas and the specific code of the diesel engine performance analysis function, such as the vibration frequency spectrum analysis and combustion heat release rate analysis, were introduced in detail. Based on the theory of vibration spectral analysis, a program was designed to analyzing the power spectral density of the original displacement signal and was called by the main program.3) Based on diesel engine6L21/31, A quasi-dimensional model was built using AVL Boost software and was verified by contrasting corresponding test datas. Based on that, a simulation model with an EGR system and a model with both EGR system and high pressure common rail system were built and calculated. And the corresponding parameters were produced to indicate that different system had different effect on the thermal parameters and the emission parameters. This would offer guidance for adding an EGR system or a high pressure common rail system for diesel engine6L21/31.