Abstract
Currently, around 80% of large ships use Bunker oil (JIS C heavy oil) as the base fuel in marine diesel engines. With its very high kinematic viscosity, this oil is considered the lowest grdae of fossil fuel. Thus, it needs to be heated to reduce its viscosity. The authors have reported that the blending of liquefied DME improved the combustion performance of Marine Diesel Oil (JIS Aheavy oil). This study aims to clarify the effectiveness of DME — Bunker oil blends. The kinematic viscosity measurement of DME and Bunker oil blended fuel was performed using a capillary tube type viscometer. A pressure cell which contains the viscometer was developed to measure the fuel viscosity while keeping DME ina liquid state. From experiments, it was shown that the cell pressurization resulted in smaller values of kinematic viscosity, and modification was needed to obtain true viscosity values. It was shown that at 323K, the kinematic viscosity of Bunker oil can be reduced drastically from 54~89% with DME blending.
