CAJ | 학술논문

针对1台单缸电控4气门发动机进行了可变进气的改进设计,使发动机进气道的流量系数、涡流比、滚流比等流动特性,随着不同的运行工况而变化,从而达到优化发动机中低负荷性能的目的.对可变进气发动机进行的台架性能及排放试验结果表明:随着节气门开度从25%上升到75%,发动机功率提高了4.37%～2.56%,扭矩提高了4.21%～2.56%,燃油消耗率降低了4.89%～2.66%.在中低负荷时,可变进气可以优化发动机的动力和经济性能,但随着负荷的增大,改善的幅度减小.同时,可变进气可使HC、CO排放降低4%～9%,而NO_x排放有所上升.
침대1태단항전공4기문발동궤진행료가변진기적개진설계,사발동궤진기도적류량계수、와류비、곤류비등류동특성,수착불동적운행공황이변화,종이체도우화발동궤중저부하성능적목적.대가변진기발동궤진행적태가성능급배방시험결과표명:수착절기문개도종25%상승도75%,발동궤공솔제고료4.37%～2.56%,뉴구제고료4.21%～2.56%,연유소모솔강저료4.89%～2.66%.재중저부하시,가변진기가이우화발동궤적동력화경제성능,단수착부하적증대,개선적폭도감소.동시,가변진기가사HC、CO배방강저4%～9%,이NO_x배방유소상승.
A variable intake system (VIS) for the electronic controlled single-cylinder four-valve engine was developed, so that the intake air flow characteristics i.e. flow coefficient of intake port, swirl ratio and tumble ratio, etc. can be controlled according to engine operation conditions for optimization of engine performance in low and medium load ranges. The engine performance and emission datas obtained on test bench show that as throttle opening rises from 25%～75%, engine power and torque increase by 4.37%～2.56% and 4.21%～2.56% respectively, and SFC decreases by 4.89%～2.66%, that demonstrates the VIS can improve evidently engine power characteristics and fuel economy at low and medium loads. However, with the load increasing further, the effects of VIS decrease. Besides, VIS also reduces HC and CO emissions by 4%～9%, but adds NO_x emission.