选择1辆满足国Ⅴ排放标准的轻型汽油车作为试验样车，应用全流稀释排放测试系统在FTP75和US06测试循环下，对车辆在不同测试工况下的N₂O排放水平、车辆N₂O排放的影响因素以及N₂O排放随着车辆里程增加的劣化情况进行了研究。研究结果表明：FTP75循环下的N₂O排放结果高于US06循环，前者是后者的4倍左右；在冷起动阶段，由于催化剂没有达到正常的工作温度，车辆会产生较多的N₂O排放，且随着燃油硫含量的增加，车辆的N₂O排放呈现上升的趋势；随着车辆里程的不断增加，车辆的N₂O排放存在一定程度的劣化。

The spray process of diesel rotary engine was studied by means of constant volume bomb, schlieren device and high speed camera. The influences of back pressure and spray pressure on spray characteristics were emphatically analyzed. The results show that the spray diffusion rate increases rapidly and then decreases step by step during the spray process. The spray cone angle decreases sharply in the initial atomization stage and remains relatively stable in the stage of secondary atomization. The increase of spray environment pressure effectively shortens the spray penetration distance and increases the spray cone angle, which provides the test data for the optimization of fuel injection timing. With the increase of injection pressure, the spray penetration distance and spray cone angle increase and the initial fuel atomization and secondary atomization hence improve, which is beneficial to improve the spray quality of rotary engine. Accordingly, the mixing state of fuel and gas for rotary engine can be improved.