【作者】

Arthur Killinger

【摘要】

该论文已在芬兰赫尔辛基举行的第28届CIMAC大会上发表。论文的版权归CIMAC所有。This paper provides in-depth research, analysis and testing results of the impact of significant volumes of water contamination in diesel fuel oil on the ability of large, medium-speed diesel engines to successfully start and operate under emergency conditions. This investigation came about from the discovery of degraded vent pipes on diesel fuel oil day tanks that could have allowed rain water to collect at the bottom of the diesel fuel oil system and potentially prevent satisfactory engine start-up and operation. Analytical and empirical results for those conditions, where there is no known analysis or operating experience, are described in detail. For the past several decades, a number of diesel engine manufacturers investigated the effect of introducing water into the combustion process by different methods such as water emulsion, direct water injection or inlet air fumigation. The goal of these tests was to demonstrate the positive effect of water in reducing diesel engine exhaust emissions. These efforts proved successful in achieving that goal, but the results have not seen wide-spread application by today’s engine suppliers and there remained the concern about the potential disadvantages of water and diesel fuel oil systems. In contrast to past investigations, this effort focused on completing a series of diesel engine combustion analyses using Ricardo’s WAVE©, 1D engine performance simulation software. The WAVE Diesel-Jet predictive combustion model was enhanced by combining the ignition delay predictions with external combustion efficiency calculations in order to predict the power loss and water concentration where the engine would still operate and sustain efficient combustion. Two different medium-speed diesel engine models were analyzed with added water content ranging from 10% to 40% water in the diesel fuel oil. The analyses demonstrated that the engines could start and operate with those percentages of water in the fuel, but that the engine output would experience a power loss or derate proportional to the water content. The validity of the analytical findings above was demonstrated by full-scale tests conducted by MPR Associates on a large diesel engine. To accomplish this, Entergy, the nuclear power plant owner constructed a simulation of the diesel fuel oil supply system at a facility having the same make and model emergency diesel generator (EDG) set. Water was introduced into the diesel fuel oil day tank by two different approaches; slow trickle flow and large slugs of water. These conditions simulated either a steady rainfall while the EDG was operating or a large volume of water collected in the system while the EDG was in standby. Under both conditions, which consisted of more than 50 hours of testing, the diesel engine and generator set responded with negligible loss of frequency or voltage. Further, the engine was confirmed to have undergone no increased wear or degradation as a result of the high levels of water in the combustion chambers.

【会议名称】

第28届CIMAC会议

【会议地点】

芬兰 赫尔辛基

【下载次数】

3

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