热管抑制爆炸火焰和压力波的耦合热效应研究

A lot of thermal energy will be released when the flammable gas explode. If the quantity of the heat explosion cannot quickly spread out, and there could occur a fire danger. Based on this, it is proposed the heat pipe composite structure used in the flame retardant and the suppression explosion.When the explosion takes place in the pipe, at this time the heat pipe can be started the heat of combustion was served as a heat pipe power. The heat pipe can transmit quickly heat with the form of liquid gas phase change. When the blast wave reaches the metal heat pipe structure, which can make energy weaken and even flame quenching. It is promising to realize rapid quench fire and protect the fire equipment for the use of heat pipe.In order to substantially suppress the shock waves resulting from gas explosions as well to reveal the mechanism of explosion flame quenching by compound heat pipe construction. The physical model of compound heat pipe construction suppressing shock wave of gas explosion is established. The heat pipe can play a dual role in suppressing the combustion flame and shock wave of gas explosion. Starting from chemical reaction dynamics and chain-branching reaction theory, the suppression combustion wave and shock wave of gas explosion mechanism are elaborated in details. The quantitative relation between the composite structural geometric parameters and the free radicals sustaining gas combustion reaction concentration change rule are established. The physical model of gas explosion wave coupling flow process is established. The quantitative relation between the heat pipe structural parameters and shock wave energy attenuation is proved. It is illustrated the microcosmic energy mechanism of the heat pipe structure quenching flame. The new theory of explosion suppression will be gradually completed in order to provide the technical support for the development of practical explosion-proof products. The microscopic energy mechanism of micro-channel construction quenching flame is revealed. The research results make the research on explosion suppression from macro to micro field, as well as it provide theoretical grounds for development of heat pipe suppressing multiple and continuous gas explosions.

在爆炸发生瞬时会释放大量热量，如果这些热量不能及时快速导出，在阻火器另一侧就存在着火危险。基于此提出利用热管复合结构的高效相变传热来快速扩散爆燃热量从而有效达到阻燃防爆。发生爆燃时的燃烧热量正好作为热管热源而驱动热管启动，此时热管以液气相变形式迅速将火焰燃烧的热量导出，同时这种热管复合结构有望实现火焰和压力波的双重抑制。为了揭示热管复合结构抑制火焰和压力波的耦合热效应，建立该结构在跨尺度效应下抑制爆炸火焰和压力波的耦合微观热动力学模型，从热反应动力学和链式反应理论两方面来探索该结构对爆炸火焰和压力波的双重抑制机理。明晰热管结构几何参数与支持燃烧的自由基浓度变化规律的定量关系式。本研究旨在揭示热管对爆炸火焰和压力波的双重耦合抑制关键机理。对丰富和完善爆炸抑制理论，开发新型抑爆装置具有重要意义。

瓦斯爆炸后，高强度压力和大量热量同时释放，爆炸能量和压力波的耦合作用将会导致灾害程度和作用范围增大。如果能够阻断爆轰波及火焰的传播并及时把爆炸热量传递出去，对于抑制爆炸的热破坏作用是至关重要的。基于此本项目以高速导出高压高热为目标，提出热管泡沫复合多孔结构、多孔泡沫金属辅助真空腔多孔结构及动力式智能阻隔爆装置。建立数学模型分析了泡沫金属及热管复合结构用于阻火器抑爆的效果。插入热管位置一定对不同厚度内置管道填充两种不同孔径的铁镍金属泡沫抑爆特性进行了数值模拟研究，并与空管型管道和单内置泡沫铁镍金属型管道进行对比。从能量、动量、熵的角度分别分析了真空腔及多孔泡沫金属阻火降压机理，分析了复合多孔结构传热传质及淬熄机理。发现在泡沫金属结构参数一定时,传热因子和摩擦因子都随流体雷诺数Re的增大而递减，提出了一种简化的泡沫金属十四面体胞孔模型，拟合得到了其传热准则关系式。通过微观模型得到了泡沫金属的传热因子和摩擦因子的关联式。结果表明在流体流经泡沫金属骨架时直接冲刷泡沫金属骨架，减薄流动和热边界层，改变了速度矢量与温度的分布，能够快速导出火焰的高热量而达到抑制爆炸的效果。分别模拟了空管、障碍物、真空腔、多孔泡沫金属不同参数组合下的抑爆效果，计算结果表明内置泡沫铁镍金属可使爆炸温度快速下降，内置复合热管通过相变形式可以快速导出能量。从而热管泡沫复合结构可以使得火焰压力波得到有效衰减。对障碍物和真空腔分别位于管道不同位置，多孔泡沫金属不同厚度及不同孔径进行组合模拟，证实所提泡沫金属辅助真空腔作用复合多孔结构抑爆可行且高效。所研究内容为防燃抑爆装置研制及研究提供新思路，为阻火装置的设计提供新方法，将对工业抑爆、隔爆和淬火等安全技术提供理论依据。为下一步开展抑制爆炸提供新思路，对于降低瓦斯爆炸的危害保障人民生命财产安全有着重要的现实意义。