Relationship between Mass Burnt Fraction 50% Crank Angle and Low-Frequency Components in Cylinder Pressure

Keiichi Nagashima (Honda R&D)･Kazuo Tsuchiya (Meiji University)

A method for estimating the mass burnt fluctuation of 50% crank angle (MBF50%CA) using the amplitude of the fourth-order sin component (b4) include the cylinder pressure has been confirmed. In a typical gasoline engine, the maximum cylinder pressure is between 0 degrees and 45 degrees, and this cycle fluctuation affects b4. The sine wave part of the b4 calculation equation was divided into sections for each node, and the cumulative value was investigated. As a result, the reason for the relationship between b4 and MBF50%CA has been clarified.

Wall Impinging Spray Feature in a DISI Engine under Steady State Cross Flow Fields
-Effects of Cross Flow Velocity and Injection Pressure on Liquid Film Formation-

Tomohiro Ishiguro･Dai Matsuda･Eriko Matsumura･Jiro Senda (Doshisha University)･Shigenori Haraguchi･Yoshihisa Sato (Honda Motor)

Direct Injection SI engines have problems of PM emission and oil dilution. In this study, visualization measurements of wall-impinging sprays were performed under the condition of in-cylinder flow in order to understand the spray formation and liquid film behavior of wall-impinging sprays in a flow field. In this paper, we report the results obtained by changing the cross flow velocity and the injection pressure.

Analysis of Knocking Occurs Under High Speed and High Load Conditions in a Turbocharged Gasoline Engine

Changzhi Zeng･Tatsuya Kuboyama･Yasuo Moriyoshi (Chiba University)

In this study, experimental and numerical analysis of a knocking that occurs at high load and high-speed conditions in a production turbocharged SI gasoline engine was conducted. The effects of the spatial distributions of temperature and fuel concentrations on autoignition in the unburned zone and the magnitude of the following pressure oscillations were investigated.

Effect of Combustion Characteristics on In-cylinder Pressure Oscillation

Tatsuya Kuboyama･Naruki Ezawa･Itsuki Hongo･Yasuo Moriyoshi (Chiba University)

The objective of this study is to clarify the dominant factors of the in-cylinder pressure oscillation in a spark ignition engine. Simultaneous visualization of the in-cylinder flow and flame propagation was conducted using an optically accessible engine to investigate the effect of flame propagation behavior on the heat release rate and the high-frequency components of the in-cylinder pressure oscillations.