The main objectives of engine development, given the increased environmental regulations, are performance and efficiency improvement, and emission reduction. Notably, for diesel engines, the significance of fuel consumption and emission reduction is increasing because they emit harmful materials (PM, NOx); however, they are characterized by relatively low CO₂ emission in comparison with gasoline engines. Various technologies have been developed to solve these problems of diesel engines; however, majority of the diesel engines are developed in a steady state, and yet their certification and evaluation include the transient state. The transient operation of diesel vehicles leads to additional fuel consumption and emission of NOx; however, the impact of transient operation has not been discussed thus far. Therefore, this study quantitively investigates the fuel consumption and NOx emission during the transient operation of a diesel vehicle. First, the engine and vehicle’s efficiency and NOx emission differences are derived and analyzed in the steady state. Subsequently, the effects of the vehicle’s transient operation are analyzed. A vehicle’s transient operation can be classified into two types: operational and thermal transient effects. Finally, the respective transient effects are quantified and analyzed.

鉴于环境法规的增加，发动机开发的主要目标是提高性能和效率以及减少排放。值得注意的是，对于柴油发动机而言，由于排放有害物质（PM、NOx），油耗和减排的重要性日益增加；然而，它们的特点是相对较低的 CO ₂排放与汽油发动机相比。已经开发了各种技术来解决柴油发动机的这些问题；然而，大多数柴油发动机是在稳定状态下开发的，但它们的认证和评估包括瞬态。柴油车的瞬态运行会导致额外的油耗和NOx的排放；然而，到目前为止还没有讨论瞬态操作的影响。因此，本研究对柴油车瞬态运行过程中的燃料消耗和氮氧化物排放进行了定量研究。首先，在稳态下推导出和分析发动机和车辆的效率和NOx 排放差异。随后，分析了车辆瞬态运行的影响。车辆的瞬态运行可分为两类：操作和热瞬态效应。最后，对各自的瞬态效应进行量化和分析。