CAJ | 학술논문

以单缸风冷四冲程的林用小型汽油机为研究对象，采用气瓶供氧的方式，依次提供氧体积分数为21％的常态进气和氧体积分数分别为22％、23％、24％、25％和26％的5种富氧比例混合进气；保持节气门开度为25％不变，选择3000、3500、4000、4500、5000和5500 r/min 共6个速度点，进行速度特性试验；保持转速为4000 r/min 不变，选择0．5、1、1．5、2、2．5、3、3．5和4 kW 共8个负荷点，进行负荷特性试验；待林用小型汽油机工作稳定后，测定其动力性和经济性指标数据并进行对比分析。试验结果表明，富氧进气能够提高吸入林用小型汽油机的混合气热值，提高其燃烧效率，增加其有效输出功率，增强其动力性能；同时能够提高林用小型汽油机的能量转化率，降低其燃油消耗率，达到优化其经济性能指标的目的；相对于氧体积分数为21％的常态进气，氧体积分数分别为22％、23％、24％、25％和26％的富氧进气条件下，各个转速点的功率平均升高率分别为6．1％、14．2％、20．6％、29．7％和38．9％，各个负荷点的油耗率平均降低率分别为8．8％、17．9％、24．8％、32．8％和42．9％；富氧进气能够同时改善林用小型汽油机的动力性及经济性，并且富氧进气的氧体积分数越高，改善的效果越明显。
이단항풍랭사충정적림용소형기유궤위연구대상，채용기병공양적방식，의차제공양체적분수위21％적상태진기화양체적분수분별위22％、23％、24％、25％화26％적5충부양비례혼합진기；보지절기문개도위25％불변，선택3000、3500、4000、4500、5000화5500 r/min 공6개속도점，진행속도특성시험；보지전속위4000 r/min 불변，선택0．5、1、1．5、2、2．5、3、3．5화4 kW 공8개부하점，진행부하특성시험；대림용소형기유궤공작은정후，측정기동력성화경제성지표수거병진행대비분석。시험결과표명，부양진기능구제고흡입림용소형기유궤적혼합기열치，제고기연소효솔，증가기유효수출공솔，증강기동력성능；동시능구제고림용소형기유궤적능량전화솔，강저기연유소모솔，체도우화기경제성능지표적목적；상대우양체적분수위21％적상태진기，양체적분수분별위22％、23％、24％、25％화26％적부양진기조건하，각개전속점적공솔평균승고솔분별위6．1％、14．2％、20．6％、29．7％화38．9％，각개부하점적유모솔평균강저솔분별위8．8％、17．9％、24．8％、32．8％화42．9％；부양진기능구동시개선림용소형기유궤적동력성급경제성，병차부양진기적양체적분수월고，개선적효과월명현。
@@@@Small gasoline engines for forestry with single cylinder air-cooled four stroke were selected as experimental objects and normal intake air with oxygen volume fraction of 21% and five kinds of oxygen-enriched mixture intake air with oxygen con-tents of 22%, 23%, 24%, 25% and 26% were provided in Oxygen cylinder.With 25% of the opening degree of throttle valve, six speed points of 3 000, 3 500, 4 000, 4 500, 5 000 and 5 500 r/min were selected to test the velocity characteris-tics.With 4 000 r/min, eight load points of 0.5, 1, 1.5, 2, 2.5, 3, 3.5 and 4 kW were selected to test the load charac-teristic.When the small gasoline engines for forestry worked stably, the dynamic property and the economy index were measured and compared.The test results show that oxygen-enriched intake air can improve mixture calorific value, com-bustion efficiency, effective output and dynamic property by small gasoline engines for forestry.Oxygen-enriched intake air can also improve energytransformation ratio, fuel consumption rate and economy index of small gasoline engines for forest-ry.Compared with normal intake air with oxygen content of 21%, the power ofevery speed point with oxygen contents of 22%, 23%, 24%, 25% and 26% increases by an average rate of 6.1%, 14.2%, 20.6%, 29.7% and 38.9%, re-spectively.The fuel consumption rate of every load point declines by an average rate of 8.8%, 17.9%, 24.8%, 32.8%and 42.9%, respectively.Oxygen-enriched intake air can improve both dynamic property and economy of small gasoline engines for forestry.The higher the oxygen concentrations are, the more obvious the improvements are.