罗琳，钱叶剑，龚震，齐景晶
（合肥工业大学 汽车与交通工程学院，安徽
合肥 230009）
摘要：本文利用GT-POWER7.3软件建立了长城GW2.5TCI柴油机仿真计算模型，模拟研究了喷油策略对柴油机动力性和排放性能的影响。计算结果表明：若柴油机的每循环供油总量不变，合适的预喷量能提高中高转速下动力性，但后喷会降低柴油机的动力性，且后喷量越大，动力性能下降越明显。适量的预喷能降低柴油机低转速下NOX排放，但Soot排放有所增加；后喷会增加低转速下NOX排放，且NOX排放随着后喷量的增加而增加，但Soot排放则随着后喷量的增加而减少；高转速下，后喷对NOX和Soot排放影响不大。因此，长城GW2.5TCI柴油机在中低转速范围内可进行适量的预喷和后喷，以提高动力性同时降低NOX和Soot排放。
关键词：柴油机；喷油策略；数值模拟；排放控制
Abstract: In this paper, the simulation model of GW2.5TCI diesel
engine is established by using the software named GT-POWER7.3, and the
influence of the power and emission performance of the engine is simulated and
studied by using different injection strategies. Results show that, when fuel
is delivered with the same amount in per engine cycle, the appropriate
pre-injection can increase the power performance in middle and high speed, but
post-injection can reduce the power of the engine; and when the quantity of
post-injection is more, the power performance decreased more extremely. An
appropriate amount of pre-injection can reduce NOX emission at low
speed, but the emission of the Soot increases. At low speed, the post-injection
will lead the NOX emission to increase and the Soot emission will
decrease with the increase of the amount of the post-injection. The
post-injection has a little effect on the emissions of NOX and Soot
at high speed. Therefore, at low and middle speed of the GW2.5TCI engine, the
appropriate amount of pre-injection and post-injection should be carried out,
which can improve the power performance and reduce the NOX and Soot
emissions.
Keywords: Diesel Engine; Strategy of the Injection; Numerical Simulation;
Emissions Control
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