【摘要】 利用瞬态控制和测试系统,研究了增压柴油机恒转速增转矩瞬变工况不同加载时间和转速对发动机动态响应及燃烧劣变的影响.为分析问题的方便,定义了一个评价瞬变响应性能的参数——滞后系数.结果表明:在相同加载时间下,发动机的油量、转矩、进气量和NOx的滞后系数依次增大;随着加载时间或转速的减小,各参数的滞后系数逐渐增大;与稳态工况相比,瞬变过程中发动机存在进气延迟、空燃比降低、燃烧相位推迟、烟度和燃油消耗率增加等燃烧劣变问题,且随着加载时间或转速的减小,上述的"问题"越严重.更多还原

【Abstract】 Using transient measurement and control system,the effects of constant speed and increasing torque on dynamic response and combustion deterioration of a turbocharged diesel were experimentally investigated. To facilitate the analysis,the lag coefficient was defined which refers dynamic response speed. Results show that the dynamic response speeds of fuel,torque,intake air and NOx are decreased and corresponding lag coefficients are increased under the same transient operation. The lag coefficients are increased when shortening the transient time while decreased when increasing the engine speed. Compared with the steady-state conditions,engine demonstrates such phenomena like intake air delay,airfuel ratio decreasing,combustion phase delay,smoke and CO emissions increasing. Furthermore, these phenomena much worse as the loading time or constant speed decreasing.更多还原