【作者】

Johann Wloka

【摘要】

该论文已在赫尔辛基举行的第28届CIMAC大会上发表，论文的版权归CIMAC所有。ABSTRACT The steady development of Diesel Engines in the scope of Marine and Power Engineering, focus on mainly two main targets – the simultaneous reduction of fuel consumption and exhaust gas emissions at low life cycle costs. Many new engine concepts have been developed in order to achieve the high market and emission requirements. One indispensable feature of future Diesel engines is a high performance Injection System, which allows to control the mixture formation and the combustion process precisely, in order to achieve the high-sophisticated consumption- and emission-goals. MAN Diesel & Turbo SE has a long history in developing and producing Conventional and Common-Rail Injections Systems for medium speed Diesel engines. In the future, especially in combination with exhaust gas aftertreatment systems, the control of the mixture formation in the combustion chamber, for example with multiple injections and variable injection timing, plays a major role for the Diesel Engine combustion process. Due to this reason, MAN Diesel & Turbo SE decided to develop a new modular Common Rail System with 2200 bar rail-pressure, the CR 2.2 – System. In this paper MAN Diesel & Turbo SE wants to show the main features of the new developed MAN CR 2.2 – System and give also a precise description of all the efforts and optimizations made during the engineering work. Beginning with a detailed hydraulical simulation analysis of the systems main concept and the injector layout, the paper will show performance test bench results, like the injection rate and highlight the possibility of stable multipleinjection events, which are needed to achieve further emission goals. From these simulation and test bench results, the benefits for the atomization-, mixture formation- and subsequently the combustion process will be shown and described. 2200 bar rail-pressure increases the fuel atomization process and subsequently the mixture formation. Unfortunately, Cavitation is also increased due to high fluid velocities. One major development goal is to optimize the cavitation in the nozzle and the whole injection system. To achieve a better understanding of cavitation formation, two-phase CFD Methods and CT – Scan Analysis for detailed nozzle cavitation prediction have been used during the development process. The optimization of nozzle fluid flow is a crucial development task to achieve high service life, and will be discussed in the paper. In order to evaluate the spray process and gain a better understanding of the atomization, optical investigations on the MAN Injection Spray Chamber have been carried out. The analysis of spray data, like penetration length and spray angle, allows the evaluation of the spray process as a function of geometrical nozzle parameters. The use of optical diagnostic methods during the development phase will be discussed and the results linked to engine mixture formation. The paper will also describe the performance tests of the CR 2.2 – Injection System on various test Engines. The MAN Diesel & Turbo SE tool chain contains, besides Single Cylinder Research Engine Tests, in-house engine test and field test with customer engines in real operation mode. The achieved results will be described and discussed. The paper will summarize the benefits of the new developed MAN CR 2.2 – Injection System compared to conventional injection systems and the well-established MAN CR 1.6 – Injection System, and will finish with an outlook of future developments. Powered

【会议名称】

第28届CIMAC会议

【会议地点】

芬兰 赫尔辛基

【下载次数】

2

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