报告从宏观政策环境、地方政策动态、竞争对手情报、产品与技术创新等几个方面进行了分析及评论。

报告从宏观政策环境、地方政策动态、竞争对手情报、产品与技术创新等几个方面进行了分析及评论。

报告从宏观政策环境、地方政策动态、竞争对手情报、产品与技术创新等几个方面进行了分析及评论。

The history of tires dates back to the mid-1800s, during which only rubber tires, best known as solid tires, were used. Advances in technology led to the replacement of solid tires by pneumatic tires. They were first used in automobiles by the Michelin brothers, who went on to become one of the prominent tire vendors in Europe. Over time, the Tire market witnessed new breakthroughs in technology and the entry of many vendors.

Tires track their history back to the mid-1800s, at which time they were made of rubber, best known as solid tires. With time and new advances, solid tires were replaced by pneumatic tires, which were first used in automobiles by the Michelin brothers, who went on to become one of the prominent tire vendors in Europe. Over time, the Tire market has witnessed new technology breakthroughs and the entry of many vendors.

以某重型柴油机为研究对象,在低速中等负荷工况,通过对比进气门晚关机构开闭两种状态对两级增压系统匹配关系的影响,分析其对柴油机排放和热效率的影响。研究表明,喷油定时(上止点后-2.5°~8.5°)和EGR率(0%~21%)恒定时,使用进气门晚关(IVCA)机构后HC排放降低,有效热效率下降。当喷油定时不变,BNOxdif与BCOdif随着EGR率的增加而减少;当EGR率保持恒定时,随着喷油定时增加,BCOdif呈现先增加后减小的趋势,拐点在4.5°~6.5°(ATDC)之间;同时,开启IVCA机构后,EGR率在15.29%~21.16%,喷油定时在-2.5°~8.5°(ATDC)范围内,Bsootdif均小于0。在保证喷油定时恒定时,EGR率越大,Bsootdif越小。当量比在0.42~0.52范围内,保持喷油策略不变,使用IVCA机构致使进气流量减少,若当量比在原状态的基础上增加超过0.07,即可克服由于流量减少导致柴油机缸内平均温度和燃烧持续期增加对NOx生成的负面影响。

采用同步辐射X射线小角散射(SAXS)方法测量了柴油机在标定工况,燃用添加4种不同比例(0、0.25%、0.5%、0.75%)二叔丁基过氧化物(DTBP)的生物柴油时,排放颗粒的粒径,并与扫描电镜和透射电镜进行了对比,研究了燃料十六烷值对排放颗粒粒径分布的影响规律。结果表明,SAXS方法可用于柴油机颗粒粒径的测量,以获得单个颗粒粒径的统计分布数据,使测量结果不受颗粒团聚的影响;颗粒粒径近似呈正态分布,平均粒径在65~67nm之间;随着DTBP添加比例的增加,燃料的十六烷值升高,颗粒的平均粒径略有减小。

针对目前应用广泛的发动机冷却风扇类型,开发了兼容性的控制策略。首先针对有级调速、无级调速电子风扇及硅油离合器风扇的特点,以风扇转速作为目标控制量,根据发动机工况参数计算冷却风扇目标转速;然后基于风扇控制模式选择字对风扇的控制模式进行仲裁控制,获得当前控制模式对应的风扇转速百分比;最后将风扇转速百分比转换成与风扇控制类型对应的控制信号。控制策略设计完成后,先后在HIL和柴油机台架上进行了仿真和试验研究,结果表明控制策略有效可行,缩短了发动机暖机时间,并使发动机热机水温稳定在(85±3)℃,有效降低了燃油消耗率。