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The Diesel Particulate Filter (DPF) modeling has been used to predict the pressure drop, deposited soot mass and regeneration of DPF. But the prediction of DPF behavior requires the experimental data in which the most important parameter is hydrodynamic resistance factor. In this research, it was obtained as a function of particle's approach velocity. Also, the relations between the pressure drop and deposited soot mass were obtained experimentally. In order to investigate the characteristics of soot loading and oxidation behavior within DPF, a partial flow system was designed which can be used to measure important parameters at the same temperature and flow rate with those of the single channel DPF.

In this study, an investigation of the transient knock characteristics in a four cylinder DOHC spark-ignition engine has been carried out. We simulated the behavior of an engine during the rapid acceleration of a car using an eddy current type dynamometer. In a commercial ECU, spark timing was retarded from the steady state value during rapid acceleration to prevent uncomfortable feeling and knock. Knock usually occurred just after the start of acceleration when spark timing was advanced from the value set by the commercial ECU. We found that air/fuel ratio was about stoichiometric for a knocking cycle. Transient knock control logic was developed which used air/fuel ratio information of an O2 sensor as a control input. Torque was improved during rapid acceleration by using the transient knock control.