论文部分内容阅读
为了研究防风网的屏蔽功能,用理论分析的方法建立了防风网动力效应的数学模型.采用数值计算与风洞实验结合的方法研究了防风网前后的流场分布特点和网后风速的衰减规律.研究表明:在网后0~10倍网高的长度范围内,风流有40%~60%的衰减幅度.根据这个结果,以一大型露天煤粉堆场为实例,在煤堆场的上风向设置防风网,通过对堆垛表面摩擦风速的计算,得出该方案下堆垛煤尘的起尘率仅为37.40%,明显小于无网防护下煤尘73.6%的起尘率,表明设置防风网能有效降低煤尘表面的摩擦风速,减少煤尘的风蚀扬尘量.
In order to study the shielding function of the windbreak, the mathematic model of the windbreak dynamic effect was established by the theoretical analysis method.The numerical simulation and the wind tunnel experiment were used to study the distribution characteristics of the wind field before and after the windbreak and the attenuation law of the wind speed behind the windbreak The results show that there is a 40% ~ 60% attenuation of the wind flow within the range of 0 ~ 10 times the net height of the net.According to this result, taking a large open pit coal yard as an example, According to the calculation of the frictional wind speed on the stack surface, it is concluded that the dust collection rate of stack dust under this scheme is only 37.40%, which is obviously less than that of 73.6% of the coal dust without mesh protection, indicating that setting Windproof mesh can effectively reduce the frictional velocity of coal dust on the surface and reduce the amount of dust eroded by coal dust.