Abstract
Keywords:
LII (Laser-Induced Incandescence), LIS (Laser-Induced Scattering), Soot, Diesel Engine
Abstract
An Increased interest in particulate size distributions and nano-particle emissions from diesel engines was sparked by reports that new technology engines may still generate high particle numbers. Modern medical research is reporting that small size particulates are more harmful to humans than the larger ones. Much more medical research and diesel emission studies are needed to fully characterize the diesel nano-particle emissions and their impact on human health. For this study, further investigations are necessary in order to improve various measurement techniques of the diesel nano-particle emissions with quantitative information. The soot formation and oxidation process inside the combustion chamber of a DI diesel engine was investigated by using two-dimensional laser-induced incandescence (LII) and laserinduced scattering (LIS) method. For this measurement method, a thin laser sheet beam was introduced into the piston bowl of an optically accessible diesel engine, which has a common rail fuel injection system with a bosch 6 hole injector. The image detection was performed perpendicularly to the incident beam through a transparent piston bottom window and a mirror which was mounted inside the slit of the elongated piston. One Intensified CCD camera was used to obtain two-dimensional laser-induced signal images by using a optical image splitter. For the calibration, light extinction and scattering method was used. After calibration of the LII and LIS method via results of extinction and scattering method, such as soot volume fraction, diameter, and number density, the LII and LIS method was applied to a transparent single cylinder engine.