Abstract
Large two-stroke marine diesel engines have high thermal efficiency and use inexpensive marine diesel fuel (MDF) . Such engines can contribute to control of global warming by low CO2emission. However, polluting matter, NOx, , SOx, and PM are discharged in large quantities, and countermeasures are required for environmental protection. It was reported that fuel-water emulsion was effective to reduce emissions and to improve combustion. Micro-explosion phenomena and the behavior of water particles in the droplet of emulsified fuel are not clear enough for understanding the effects on combustion, however. This paper introduces an experimental study on combustion of a single droplet of water-in-fuel emulsion of MDF at high temperature and in a high-pressure chamber.
The experimental results show that, in an atmospheric experiment, when the mean diameter of the water particles increases, the micro-explosion becomes violent and the burning time and ignition delay become shorter; on the other hand, in a high-pressure experiment, when the initial pressure of the chamber increases, the projected flame area becomes smaller and the micro-explosion becomes weaker.
