冷起动环境下车辆风窗玻璃除霜特性研究

Study on Defrosting Characteristics of Vehicle Windshield in Cold-Start Environments

喷射气流环境和热力状态参数是合理设计汽车风窗玻璃除霜系统的基本因素,二者存在着复杂的互动关联关系。通过研究喷射气流出口速度、温度和环境初始温度等参数对风窗玻璃除霜的影响,分析了风窗玻璃特征点温度、平均温度、平均液相率和液态分数等除霜相变特性的变化规律。结果表明,风窗玻璃表面温度在除霜过程中存在3段变化,即急升段、解霜相变段和缓升段,各阶段分别决定了除霜效果。

The airflow jet environment and thermal status parameter are the essential factors for a reasonable windshield defrosting system design and they are interacted with each other in a complicated way.The changing rule of defrosting characteristics including characteristic dot temperature,average temperature,average liquid rate and liquid state fraction etc.is analyzed by studying the effects of airflow jet speed,temperature and ambient temperature on windshield defrosting performance.The results show that the temperatures on windshield in a defrosting process have three periods, including rapid rise,phase-change of thaw and slow rise,and each period determines the defrosting effect separately.