中文摘要：

为改善燃烧室内喷雾的空间分布，促进油气更好地混合，设计了一种新的直喷式柴油机撞壁喷雾燃烧室。对不同喷孔夹角在燃烧室内形成的近撞（包括全撞和半撞）及远撞喷雾方式的缸内混合气形成与燃烧过程进行了数值模拟。结果表明，从燃空比分布来看，半撞喷雾方式混合气最均匀，全撞方式次之，远撞方式最差。至于排放，远撞喷雾方式生成的NO排放最低，而半撞喷雾方式生成的碳烟排放最低。

英文摘要：

In order to improve the spatial distribution of fuel spray in combustion chamber and achieve better fuel-air mixing, a novel spray-wall impingement type of combustion chamber is designed for direct injection diesel engine, and numerical simulations are conducted on the in-cylinder mixture formation and combustion process with different ways of spray impingement including near-wall impingement （covering full and half impingements） and distant impingement formed by different spray hole angles. The results show that in terms of the distribution evenness of fuel/air ratio, the mixture formed by half impingement spray is the best and the distant impingement the worst with the full impingement in between. As for emission the distant impingement produces the least NOx emission while the haft impingement has a lowest soot emission.