突扩巷道流场回流区边界PIV实验与数值模拟

发布时间：2018-05-08 04:44

  本文选题：矿井通风 + 突扩巷道　； 参考：《矿业安全与环保》2017年06期

【摘要】：为探究突扩巷道断面风速分布规律,准确确定流场回流区边界,利用粒子图像测速仪(PIV)对矩形均直突扩巷道流场进行测试,并对不同突扩比和不同入口风速条件下突扩流场进行数值模拟。研究结果表明:风流经过突扩巷道后流线由平滑直线发生突变,在突扩位置后上下隅角形成回流旋涡区,回流区域负值风速的存在使得回流区内速度分布呈现"Ω"型,随着距离的增加速度分布逐渐趋于稳定并呈"∩"型,断面风速由"Ω"型分布向"∩"型分布的过渡位置即为突扩巷道流场回流区边界位置;在风速0.1~2.5 m/s内,回流区边界位置随着风速的增大有较大变化,而在风速2.5~25.0 m/s内,回流区位置随风速的增大变化较小;当风速一定时,回流区边界位置随着突扩比的增大而距突扩过渡面越远,即回流区越长。
[Abstract]:In order to investigate the distribution of wind velocity in the section of the tunnel with sudden expansion and determine the boundary of the flow field, the particle image velocimeter (PIV) was used to test the flow field of the rectangular tunnel. Numerical simulation of sudden expansion flow field under different sudden expansion ratio and different inlet wind speed is carried out. The results show that the flow line changes from a smooth straight line after the wind flow passes through the sudden expansion roadway, and the circumfluence vortex region is formed in the upper and lower corner after the sudden expansion position. The negative wind speed in the backflow region makes the velocity distribution of the backflow zone appear "惟" type. With the increase of the distance, the velocity distribution tends to be stable and presents a "鈮，

本文编号：1860038