B211 Combustion behavior of water/oil emulsified fuel droplet under high temperature and high pressure

Abstract

Droplet of water/oil type emulsified fuel was auto-ignited under high temperature and pressure condition provided by a rapid compression machine, and the combustion behavior was observed. Initial droplet diameter was varied from 70μ to 130μ, and ambient pressure was 1.8, 2.8, and 5.5MPa. The result showed the following. For emulsified fuel, under higher pressure than 1.8MPa, micro-explosion doesn't occur, but puffing occurs. Ignition delay of emulsified fuel droplet is longer than that of gas oil, and the effect of initial droplet diameter on ignition delay is high. Moreover, burning period of emulsified fuel is shorter than that of gas oil. At 5.5MPa that is simulated diesel engine condition, puffing phenomenon and auto-ignition of droplet occurs at the same time and flame shape changes randomly.