CAJ | 학술논문

针对普通废气涡轮增压器低速响应和高速功率不能同时兼顾的特点,对可变喷嘴涡轮增压器(VNT)进行了试验研究.通过试验分析了喷嘴环叶片位置对柴油机性能的影响,并得到了VNT的优化脉谱.同时进行了VNT的瞬态响应研究.研究结果表明:VNT通过改变涡轮喷嘴环面积可与柴油机各工况实现最佳匹配,燃油消耗率在全工况范围内明显改善,在高速低负荷时燃油消耗率降低最多,达到了10 %;通过增加低速的进气量,VNT对柴油机低速高负荷工况性能有明显改善,扭矩约增加15 N·m,油耗率降低2 %,烟度从原机4.5 BSU降低到2.5 BSU;通过与原机外特性的对比,在中高速的NO_x和烟度排放与原机相差不大,在低速区NO_x增加约100×10~(-6),烟度降低2 BSU,在整个转速范围内油耗率降低2 %～3 %.
침대보통폐기와륜증압기저속향응화고속공솔불능동시겸고적특점,대가변분취와륜증압기(VNT)진행료시험연구.통과시험분석료분취배협편위치대시유궤성능적영향,병득도료VNT적우화맥보.동시진행료VNT적순태향응연구.연구결과표명:VNT통과개변와륜분취배면적가여시유궤각공황실현최가필배,연유소모솔재전공황범위내명현개선,재고속저부하시연유소모솔강저최다,체도료10 %;통과증가저속적진기량,VNT대시유궤저속고부하공황성능유명현개선,뉴구약증가15 N·m,유모솔강저2 %,연도종원궤4.5 BSU강저도2.5 BSU;통과여원궤외특성적대비,재중고속적NO_x화연도배방여원궤상차불대,재저속구NO_x증가약100×10~(-6),연도강저2 BSU,재정개전속범위내유모솔강저2 %～3 %.
Due to the fact that low-speed response and high-speed power characteristics can not be considered simultaneously for normal turbochargers, the experimental research on the variable nozzle turbocharger (VNT) was conducted, analyzing mainly the effect of the nozzle ring position of VNT on engine performance and transient response capability of the VNT, and achieving the optimized VNT map. The results indicate that the matching of VNT with diesel engine can be optimized at every operating condition by varying the area of nozzle ring. The SFC can be improved obviously at all the operating conditions, especially at high speed and low load conditions the SFC decreases by about 10 %. By increasing the mass flux of inflow, the performance of diesel engine at low speed and high load conditions is improved, torque increases by 15 N·m, SFC decreases by 2 % and smoke decreases from 4.5 BSU to 2.5 BSU. In comparing to the original engine, the engine with VNT has little difference in NO_x and smoke emissions at middle and high speed ranges, but the NO_x emission increases by 100×10~(-6) and the smoke decreases by 2 BSU at low speed range, the SFC decreases by 2 % ～3 % at the whole speed range.