Abstract: The fresh air load of automotive air conditioning is an important research object to improve the driving range of battery electric vehicles. Scholars focus on the analysis of the minimum fresh air volume and the optimization control mode, so as to reduce the vehicle energy consumption and improve the driving range. However, in terms of engineering realization, based on the current mainstream fresh air structure of automobile air conditioning, the author finds that with the increase of vehicle speed, the higher the deviation between the actual minimum fresh air volume and the theoretical demand value, the higher the additional fresh air load. Therefore, this paper proposes an improved fresh air structure, which can improve the realization degree of the theoretical minimum fresh air volume at different vehicle speeds. The computational fluid dynamics (CFD) analysis of the improved fresh air structure shows that the minimum fresh air volume can be improved from 68 m 3 /h to 33.5 m 3 /h when the speed is 120 km/h, and the control limit of the minimum fresh air volume is improved by 49%. Moreover, when the CO2 threshold is 1 000×10-6 mg/L comfort mode, the fresh air heat load at 0 km/h, 50 km/h, 80 km/h and 120 km/h is optimized by 0%, 27%, 38% and 51% compared with the existing design. When the CO2 threshold is 2 000×10-6 mg/L energy saving mode, the heat load at 0 km/h, 50 km/h, 80 km/h and 120 km/h is optimized by 58%, 66%, 58% and 51% compared with the existing design.

Key words: Automotive air conditioning; Refresh air structure; Minimum fresh air volume; Fresh air load

摘要： 汽车空调新风负荷作为纯电动汽车提升续航里程的重要研究对象，学者们着重通过分 析最小新风量和优化控制方式，进而降低整车能耗，提升续航里程。但是在工程实现方面， 基于目前主流汽车空调新风结构，笔者发现随着车速的增加，实际最小新风量与理论需求值 偏离越高，造成额外新风负荷越高，故而文章提出一种改进型新风结构，可以在不同车速下 改善理论最小新风量实现度。通过对改进型新风结构进行计算流体动力学（CFD）分析，结 果表明，在单人驾驶时，车速 120 km/h 时最小新风量可以由 68 m 3 /h 改善至 33.5 m 3 /h，最小 新风量控制极限改善 49%。而且在 CO2 阈值 1 000×10-6 mg/L 舒适模式时，在 0 km/h、50 km/h、 80 km/h、120 km/h 时新风热负荷比现有设计分别优化 0%、27%、38%、51%；CO2 阈值 2 000× 10-6 mg/L 节能模式时，在 0 km/h、50 km/h、80 km/h、120 km/h 时热负荷比现有设计分别优 化 58%、66%、58%、51%。

关键词: 汽车空调；新风结构；最小新风量；新风负荷