CIESC Journal ›› 2019, Vol. 70 ›› Issue (3): 1227-1235.DOI: 10.11949/j.issn.0438-1157.20181072

• Process safety • Previous Articles     Next Articles

Experimental study on flame propagation characteristic of polyethylene dust explosion under confined chamber

Jianliang YU(),Yujie HOU,Xingqing YAN,Wentao JI,Xiaozhe YU,Yibo WANG   

  1. School of Chemical Machinery and Safety, Dalian University of Technology, Dalian 116024, Liaoning, China
  • Received:2018-09-22 Revised:2018-12-19 Online:2019-03-05 Published:2019-03-05
  • Contact: Jianliang YU

密闭空间内聚乙烯粉尘爆炸火焰传播特性的实验研究

喻健良(),侯玉洁,闫兴清,纪文涛,于小哲,王祎博   

  1. 大连理工大学化工机械与安全学院,辽宁 大连 116024
  • 通讯作者: 喻健良
  • 作者简介:喻健良(1963—),男,博士,教授,<email>yujianliang@dlut.edu.cn</email>
  • 基金资助:
    国家自然科学基金项目(51574056, 51604057)

Abstract:

An experimental apparatus which could withstand high pressure and with good visibility was modified. PIV technology was applied to measure the distribution of cold pulverized flow field. Flame propagation characteristics of polyethylene dust explosion were investigated in closed vessel. In experiments, flame structure, flame brightness, flame front location, flame propagation speed and other parameters variation were analyzed. The results show that in the concentration range of 200—1000 g/m3, the low-concentration polyethylene dust explosion flame has a discontinuous fin-like structure, and the flame front is discrete star-shaped. On further increasing the dust concentration the flame continuity as well as the luminance increased and reached the top at the concentration of 400 g/m3. The velocity fluctuated obviously during the flame propagation process of polyethylene dust explosion at different concentrations, which increased at first and then decreased. The velocity-fluctuation of the flame was more obvious when it was close to the optimum explosion concentration range. The RMS turbulent velocity equation was adopted to quantify overall pulsation amplitude. Dust concentration was close to the optimal explosion concentration of 400 g/m3 and the RMS turbulent velocity was 3.21 m/s.

Key words: confined space, powders, turbulent flow, explosions, flame structure, flame propagation velocity

摘要:

采用竖直、可视粉尘爆炸火焰传播实验平台,结合粒子图像测速PIV技术测得喷粉的冷态流场分布,研究聚乙烯粉尘在密闭容器内的爆炸火焰传播特性,探讨火焰结构与锋面位置的动态变化、火焰传播速度等参数的变化规律。结果表明,在200~1000 g/m3浓度范围内,低浓度聚乙烯粉尘爆炸火焰呈不连续片羽状结构,火焰锋面呈离散的星点状。粉尘浓度增加,火焰连续性及亮度增强,锋面呈齿状,并在400 g/m3火焰最明亮,火焰平均传播速度均随粉尘浓度的增加先增大后减小。采用均方根湍流速度量化体系整体脉动幅度,浓度接近最佳爆炸浓度400 g/m3时,均方根湍流速度为3.21 m/s。

关键词: 密闭空间, 粉体, 湍流, 爆炸, 火焰结构, 火焰传播速度

CLC Number: