Effects of Pressure Boost on the Performance Characteristics of the Direct Injection Spark Ignition Engine Fuelled by Gasoline at Various Throttle Positions

摘要

The main objective of this study is to investigate the effect of boost boost and various throttle positions on performance characteristics of direct injection spark ignition (DISI) engine fuelled by gasoline at various throttle positions. The performance characteristics in this experimental study were measured in terms of brake torque (BT), brake specific fuel consumption (BSFC) at various engine speeds (1000 rpm, 2000 rpm, 3000 rpm, 4000 rpm and 5000 rpm), various throttle positions (TP) (25%, 50%, 75% and 100%) and various pressure boosts (10 kPa, 20 kPa, 30 kPa and 40 kPa). The tests have been performed on a 2.0 LITER MIVEC DOHC 16-valve inline, 4cylinder turbocharged direct injection spark ignition (DISI) engine. The results showed that with increase in TP from 50% to 100%, the brake torque (BT) is increase for natural aspirated (Unboosted Engine) engine. For boosted pressure engine, increase pressure boost from 0 kPa to 40 kPa; the BT also increases. The lowest BSFC result occurred at 50% to 100% TP with increasing engine speed. BSFC results at boosted pressure showed the BSFC decrease with increasing in pressure boost up to 10 kPa. Thus it can be concluded that by boosting the intake pressure (turbocharged) is one of effective ways to enhance the performance characteristics of the engine.