加氢装置是炼化企业典型的高危装置,涉及氢气等易燃易爆介质,安全风险较高。为研究加氢装置在开敞空间条件下氢气泄漏爆炸事故火焰及冲击波时空演化过程,基于FLACS三维模拟软件对某企业加氢装置建立了等比例模型,并对其进行氢气爆炸模...加氢装置是炼化企业典型的高危装置,涉及氢气等易燃易爆介质,安全风险较高。为研究加氢装置在开敞空间条件下氢气泄漏爆炸事故火焰及冲击波时空演化过程,基于FLACS三维模拟软件对某企业加氢装置建立了等比例模型,并对其进行氢气爆炸模拟研究,探究了不同当量比(ER)对氢气云燃爆超压值及温度的影响。研究结果表明,当量比(ER)在0.8~1.4范围内时,氢气爆炸的温度、超压峰值P max均随ER的增大呈先增大后减小的趋势,ER为1.05时,爆炸温度峰值及超压峰值最大,高温火焰传播范围半径约35 m,影响面积达到3800 m 2。此外,模拟结果为类似场景建筑物抗爆工程改造提供了理论指导。展开更多
Numerical simulation has been performed to investigate the DDT(Deflagration-to-Detonation Transition)mechanism by solving fully compressible reactive flow for hydrogen/air mixtures in tube with sudden cross-section ex...Numerical simulation has been performed to investigate the DDT(Deflagration-to-Detonation Transition)mechanism by solving fully compressible reactive flow for hydrogen/air mixtures in tube with sudden cross-section expansion.The results reveal the acceleration action of abrupt cross-section on DDT,which is validated by comparing the run up distance and time with corresponding long annular tube and single tube.Detailed discussion of flow field variations finds that the DDT process in cross-section abrupt tube can be divided into three stages(flame acceleration,transition to detonation,and detonation propagation stages respectively)according to different flame modes.Particularly,it is found that formation of vortex could accelerate DDT by promoting turbulent mixing of hot products and cold reactants.Further comparative analysis on DDT characteristics of cross-section abrupt tube with different annular gap lengths shows that different mechanisms dominate in the single tube zone.The conclusions in present study support the cross-section abrupt tube as a means to enhance DDT and provide an alternative potential in practical pre-detonation initiator and pulse detonation engine applications.展开更多
文摘加氢装置是炼化企业典型的高危装置,涉及氢气等易燃易爆介质,安全风险较高。为研究加氢装置在开敞空间条件下氢气泄漏爆炸事故火焰及冲击波时空演化过程,基于FLACS三维模拟软件对某企业加氢装置建立了等比例模型,并对其进行氢气爆炸模拟研究,探究了不同当量比(ER)对氢气云燃爆超压值及温度的影响。研究结果表明,当量比(ER)在0.8~1.4范围内时,氢气爆炸的温度、超压峰值P max均随ER的增大呈先增大后减小的趋势,ER为1.05时,爆炸温度峰值及超压峰值最大,高温火焰传播范围半径约35 m,影响面积达到3800 m 2。此外,模拟结果为类似场景建筑物抗爆工程改造提供了理论指导。
基金the Fundamental Research Funds for the Central Universities(Grant No.HEUCFJ170304,Grant No.HEUCFP201719)for supporting this work。
文摘Numerical simulation has been performed to investigate the DDT(Deflagration-to-Detonation Transition)mechanism by solving fully compressible reactive flow for hydrogen/air mixtures in tube with sudden cross-section expansion.The results reveal the acceleration action of abrupt cross-section on DDT,which is validated by comparing the run up distance and time with corresponding long annular tube and single tube.Detailed discussion of flow field variations finds that the DDT process in cross-section abrupt tube can be divided into three stages(flame acceleration,transition to detonation,and detonation propagation stages respectively)according to different flame modes.Particularly,it is found that formation of vortex could accelerate DDT by promoting turbulent mixing of hot products and cold reactants.Further comparative analysis on DDT characteristics of cross-section abrupt tube with different annular gap lengths shows that different mechanisms dominate in the single tube zone.The conclusions in present study support the cross-section abrupt tube as a means to enhance DDT and provide an alternative potential in practical pre-detonation initiator and pulse detonation engine applications.