Abstract: To investigate the influence of key components of the heavy-duty vehicle engine cooling system on its cooling performance, a computational fluid dynamic (CFD) simulation method is adopted. Based on three-dimensional modeling, a systematic analysis is conducted on critical parameters such as radiator air-side resistance, fan blade number, and fan speed ratio. The results indicate that the radiator air-side resistance is significantly and linearly negatively correlated with the engine's allowable ambient temperature,lower resistance allows the engine to withstand higher ambient temperatures. An increase in the fan speed ratio notably enhances the air velocity across the radiator surface, thereby raising the allowable ambient temperature in a linear fashion. Increasing the number of fan blades can improve cooling performance within a certain range. The results of the full vehicle thermal balance tests are consistent with the simulation trends, fully validating the findings and providing a theoretical basis for forward design and optimization of the cooling system.

Key words: cooling system; CFD analysis; optimizationplan; impact on cooling performance

摘要： 为探究重型汽车发动机冷却系统关键部件对冷却性能的影响规律，采用计算流体动力 学（CFD）仿真方法，基于三维建模对散热器空气侧阻力、风扇叶片数及风扇速比关键参数 进行了系统分析。研究结果表明，散热器空气侧阻力与发动机许用环境温度呈明显线性负相 关，阻力越小，发动机能够承受的环境温度越高；风扇速比的增加显著提高了散热器表面风 速，进而提升了许用环境温度，呈现线性增长趋势；风扇叶片数量的增加在一定范围内可提 升冷却性能。整车热平衡试验结果与仿真分析结果趋势一致，充分验证研究结果可为冷却系 统正向开发与优化提供理论依据。

关键词: 冷却系统；CFD 仿真分析；优化方案；冷却性能影响