The ventilation flow in a heating, ventilation and air conditioning (HVAC) module of a passenger car was investigated experimentally. Three different ventilation modes with varying temperature mode were tested to study the effect of ventilation mode on the velocity field inside the HVAC module. For each mode, more than 450 instantaneous velocity fields were measured using a particle image velocimetry (PIV) velocity field measurement technique. The instantaneous velocity fields were ensemble averaged to obtain the spatial distribution of mean velocity and spanwise vorticity. The present work highlights the usefulness of the PIV technique for the analysis of the flow inside an HVAC module. The experimental results can be used not only to understand and improve the ventilation flow of an HVAC module but also to validate numerical predictions.

中文翻译：

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不同通风模式下汽车暖通空调系统内的流动特性研究

通过实验研究了客车的暖通空调 (HVAC) 模块中的通风流。测试了具有不同温度模式的三种不同通风模式，以研究通风模式对 HVAC 模块内部速度场的影响。对于每种模式，使用粒子图像测速 (PIV) 速度场测量技术测量了 450 多个瞬时速度场。对瞬时速度场进行集合平均以获得平均速度和展向涡度的空间分布。目前的工作强调了 PIV 技术在分析 HVAC 模块内的流动方面的有用性。实验结果不仅可用于了解和改进 HVAC 模块的通风流量，还可用于验证数值预测。