沉积粉尘瞬态流动下的爆炸波结构及能量输出

Dust explosion is one of main accident types in production processes in our country at preset, which results in property loss and serious mass injuries and death usually. Dust disperses in air and cloud is formed after a dust layer is disturbed, which are a premise condition for studying local gas explosion causing the layer dust dispersed and dust cloud formed, and the dispersing dust cloud explosion. Compared with a homogeneous dust cloud explosion, the dispersing dust cloud explosion from the disturbed dust layer is a more complicated physical process. Interaction between the explosion wave and dispersing of deposited dust is a practical challenge in the explosion suppression mechanism and a frontier problem in explosion and flow science field. In this project, research contents cover: an experimental setup for local gas explosion to deflagration transition of deposited dust; the criterion for a explosion flame acceleration of dispersed dust cloud from the dust layer; correlation between the dispersing dust cloud front and the leading pressure wave from the local gas explosion in time and space; the criterion for dust dispersion caused by a leading pressure wave; distributions of transient concentration and turbulence; explosion wave structure of the dispersing dust cloud; energy output of the dispersing dust explosion. A new model evaluating a dust cloud deflagration caused by interaction between the dispersing dust and the explosion flame for a dust layer being disturbed and the deposited dust being dispersed will be developed in this project.

粉尘爆炸是我国目前主要生产事故类型之一，往往造成重大财产损失和群死群伤。沉积粉尘被诱导、弥散、形成爆炸是事故典型的物理过程，与悬浮粉尘云的爆炸相比，其物理过程更加复杂。局域爆炸诱导沉积粉尘瞬态弥散、爆炸能量演化既是沉积粉尘环境抑爆、爆炸事故预防面临的实际挑战，也是爆炸科学、流体科学中有待发展的重要课题。本项目建立局域爆炸诱导沉积粉尘瞬态弥散浓度场、湍流场的实验方法；通过实验和数值模拟，研究沉积粉尘瞬态弥散与局域爆炸先导压力波在时间和空间的耦合关系；揭示沉积粉尘瞬态弥散非均匀流场和浓度场耦合下的爆炸波结构及其非线性物理特征；研究先导波后沉积粉尘瞬态弥散浓度及湍流分布规律；研究沉积粉尘种类、粒度、沉积厚度、局域爆炸源能量等因素对沉积粉尘瞬态弥散爆炸能量输出的影响规律。

粉尘爆炸是我国目前主要生产事故类型之一，往往造成重大财产损失和群死群伤。沉积粉尘被诱导、弥散、形成爆炸是事故典型的物理过程，与悬浮粉尘云的爆炸相比，其物理过程更加复杂。局域爆炸诱导沉积粉尘瞬态弥散、爆炸能量演化既是沉积粉尘环境抑爆、爆炸事故预防面临的实际挑战，也是爆炸科学、流体科学中有待发展的重要课题。本项目建立了局域爆炸诱导沉积粉尘瞬态弥散浓度场、湍流场的实验方法；通过实验和数值模拟，研究了沉积粉尘瞬态弥散与局域爆炸先导压力波在时间和空间的耦合关系；揭示了沉积粉尘瞬态弥散非均匀流场和浓度场耦合下的爆炸波结构及其非线性物理特征；得到了先导波后沉积粉尘瞬态弥散浓度及湍流分布规律；得到了沉积粉尘种类、粒度、沉积厚度、局域爆炸源能量等因素对沉积粉尘瞬态弥散爆炸能量输出的影响规律。