接包机排风罩捕集区域受侧向风影响的研究

排风罩是局部通风系统的主要设备之一,其集尘性能直接关系到生产作业场所粉尘的控制效果,排风罩性能受诸多因素制约,当系统参数确定后,考虑外界干扰的影响就显得尤为重要。作者针对水泥行业包装作业典型生产工艺过程和现场布置,运用现场调查、试验性公式计算与数值模拟等研究方法,对包装车间接包机排风罩外部气流流场进行量化研究。通过现场调查获取流场特点与数据,由实验性公式计算和数值模拟得出排风罩捕集区域的特征距离、流场特征线及典型平面的风速分布云图。从而得出结论:侧向风对接包机排风罩捕集效率的影响很大,排风罩捕集效率下降达50%。

Study on influence of cross draft to capture zone of hood in discharging bag conveyer

Hood is one of the major equipments for factory ventilation , and its performance has the direct influence on control of the dust in factories .In gerenal the capability of hood depends on many factors of the system .Once the running parameters of the system were determined , it is most important to judge the influence of outward inter-ference .Based on the cement package process and the on-site layout , the field survey , emprical formula calculation and numerical simulation were applied to study exterior flow field of the hood influenced by the cross draft .The characteristics and geometrical dimensions of flow field were obtained by field survey , and the critical distances , the critical streamlines and the velocity contours on typical plates were obtained by emprical formula calculation and numerical simulation .The results showed that the capture efficiency of the hood was greatly influenced by cross draft, being decreased by 50%.