ผลกระทบของตัวแปรการทำงานของเครื่องยนต์ต่อลักษณะการเผาไหม้ ของเครื่องยนต์ SI / ธนกร สุไวศยวรรณ = Effects of SI engine's operating parameters on combustion characteristics / Thanakorn Suwaisayawan
This research studied the effects of engine's operating parameters; ie. engine speed, equivalence ratio, spark advance; on combustion characteristic of SI engine. In this study, single cylinder, 4-stroke, SI engine Ricardo E6 coupled with swinging field dynamometer was used. The experiments were conducted at constant engine speed of 1500, 1800, 2100 rev./min.; each at air flow rate 100%, 75% and 50% of the WOT. Equivalence ratio and spark timing were varied between 0.8 to 1.1 and 20 to 60 ℃A btdc, respectively. At each testing point, the engine performance parameters and incylinder pressure data were recorded. In order to investigate the effects of engine operating parameters on flame development angle (∆θd) and rapid burned angle (∆θd), Rassweiler and Withrow's method was employed to obtain MFB curve from the obtained in-cylinder pressure. The results were found that the more the spark advance the longer the ∆θd but the shorter the ∆θb. The richer the mixture the shorter the ∆θd as well as the shorter the ∆θb. The higher the engine speed the shorter the ∆td as well as the shorter the ∆tb.
