A Study of Optimization of NOx and SFOC on Medium Speed Diesel Engines

다국어 초록 (Multilingual Abstract)

An engine performance and combustion simulation has been carried out to investigate effective methods for NOx and specific fuel oil consumption(SFOC) reduction on medium speed diesel engines. The simulation results show that lowering the charge air temperature by 10℃, will decrease the NOx emissions by 10%. Also, Miller cycle is evaluated by performance simulation to reduce NOx emissions and SFOC at the same time. The fuel injection nozzle hole diameter, number and injection angle have been optimized to reduce NOx emissions through combustion simulation. The engine measurements have been performed to verify the performance and combustion results and to investigate the effects of the selected parameters on engine performance. The results of measurement indicate that Miller cycle and lower charge air temperature reduce 2.8% SFOC and 10% NOx emission. Fuel injection nozzle diameter 0.34㎜ results in 16.6% lower NOx emission than that of previous specification, 0.32㎜, slightly increasing SFOC, 1.3%.

목차 (Table of Contents)

• Abstract
• 1. Introduction
• 2. Performance Simulation of Miller Cycle
• 3. Effect of Charge Air Temperature
• 4. Experiment of Miller Timing and Charge Air Temperature
• 5. 3-D. Combustion simulation
• 6. Conclusions
• References