In extreme ambient conditions, engine temperature and air charge temperature (ACT) can be so high that they compromise the vehicular performance. To preserve the structural engine reliability, it is necessary to reduce the load through an increase in the engine speed to maintain the power output, which minimizes fuel conversion efficiency degradation. However, high engine speeds also lead to enhanced friction losses and combustion frequency, which reduces the engine thermal efficiency. Therefore, this work seeks to numerically study the best thermal management strategy to minimize performance losses arising from an engine power derate strategy, while also optimizing the design of a cooling system to withstand extreme engine stress conditions, characteristics of the Davis Dam tests. Different radiator lengths and fan power were numerically simulated to conclude about the most influential parameter on fuel consumption in the FTP-75 + HWFET cycle. The results showed positive effects from the engine power derate strategy, and the engine speed control was able to mitigate up to 23% derate by cooling temperature. There was a 0.8% increase in fuel consumption for every 2.5% aerodynamic drag coefficient increase, which reinforces the need to perform robust thermal management procedures instead of oversizing a vehicular cooling system for high-load operation.

在极端的环境条件下，发动机温度和进气温度（ACT）可能很高，以至于损害了车辆的性能。为了保持发动机的结构可靠性，有必要通过提高发动机转速来降低负荷，以维持动力输出，从而将燃料转换效率的下降降至最低。但是，高发动机转速也会导致摩擦损失和燃烧频率增加，从而降低发动机的热效率。因此，这项工作旨在对最佳的热管理策略进行数值研究，以最大程度地降低因发动机功率降低策略而导致的性能损失，同时还优化冷却系统的设计，以承受极端的发动机应力条件和戴维斯大坝试验的特性。对不同的散热器长度和风扇功率进行了数值模拟，以得出关于FTP-75 + HWFET循环中对油耗最有影响的参数。结果显示了发动机功率降低策略的积极效果，并且发动机速度控制能够减轻冷却温度导致的最大23％的降低。每增加2.5％的空气动力阻力系数，油耗就会增加0.8％，这增强了执行强大的热管理程序而不是为了高负荷运行而使车辆冷却系统尺寸过大的需求。