Search Results

This study proposes a new stratified charge system for low emission and ultra lean burn. Combustible mixture was induced around sparkplug using a spherical piston cavity and up-right straight port in the general method of stratified charge. A new method of stratified charge is proposed using an injector-type spark plug in this study. This system injects fuel of extremely small quantities and ignites the mixture around the spark plug gap. The injector-type spark plug was fixed in a visualized constant volume chamber. The combustion characteristics were compared with that of the conventional ignition method. The combustion characteristics and lean combustible limits were examined, and then a photograph of flame luminosity was taken by a high speed camera with an equivalence ratio.

This experimental study was carried out to obtain fundamental data on a radical engine operation using a radical induced injection method to expect both low emission and high efficiency by rapid bulk combustion. Two kinds of experiment were conducted for the purpose. First of all, the basic experiments were conducted to confirm rapid bulk combustion by using a radical induced injection method in a constant volume chamber. In this experiment, the higher combustion velocity is realized much more than in a conventional method. Next, the fundamental data were applied to an actual engine so as to obtain fundamental data on a radical engine operation by radical induced injection. A subchamber-type diesel engine was reconstructed to a SPI type engine with controlling the injection duration, spark timing and finally converted to a radical engine.

In order to clarify the characteristics of soot formation and oxidation in cylinder of diesel engine, it is necessary to diagnose accurately for combustion of in-cylinder. The past techniques for soot measurement have limitations in providing the characteristics of soot in a diesel engine, whereas, laser-based 2D imaging diagnostics have the potential to provide better temporally and spatially resolved measurements of the soot distribution. The technique using laser sheet beam has been applied to an optically accessible diesel engine for the quantitative measurement of soot. The results provide the information for reduction of soot from diesel engine. We used both LIS and LII techniques simultaneously in this study. The images of LIS and LII show the quantitative distribution of the soot concentration in an optically accessible diesel engine. In this study, several results were obtained by the simultaneous measurement of LIS and LII techniques.