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长期以来，工业上都广泛采用多层金属丝网结构阻火器（系统），但其理论计算问题一直没有得到解决，全靠制造商的测试结果来决定。文中的实验旨在研究金属丝网结构对开敞空间预混乙炔—空气爆燃波的抑制效果，并描述了金属丝网层数、气云半径等参数对丝网结构内外两侧压差的影响。结果显示，在给定的气云半径以及丝网结构半径条件下，丝网结构内外两侧压差随着丝网层数的增加，先减小后增大，存在着一个最小值；特定的丝网结构，将对某一特定半径气云的爆燃波起到最佳的抑制效果。另外，通过与同样气云条件的开敞空间爆炸压力场进行比较发现，单纯地增加丝网层数并不是最好的抑制爆燃波的有效方式。

SUPPRESSING EFFECT OF METAL MESH CONSTRUCTION ON DEFLAGRATION WAVES IN UNCONFINED SPACE 1)

For a long time, flame arresters (system) with multi layers metal mesh are widely used in the industry. But the problem of their theoretical calculation hasn’t been solved. Their performance is decided with the testing results made by the manufacturer. The experiments conducted here attempt to study the suppressing effect of metal mesh construction on deflagration waves of premixed acetylene air mixture in unconfined space, and the influence of the parameters, such as the layer amount of metal mesh, the radius of gas cloud, etc., on the pressure difference between inside and outside of the metal mesh. The results show under a certain radius of gas cloud and mesh construction, as the layer amount of the mental mesh increases, the pressure difference between inside and outside of the metal mesh first decreases, then increases. So, there exists a minimum value for the pressure difference. With a given mesh construction, the optimal effectiveness of suppressing deflagration waves can be obtained for a special radius of gas cloud. In addition, comparing the pressure fields of explosion in unconfined space under the same conditions of gas cloud, it is found that only increasing the layer amount of metal mash isn’t the best way to suppress deflagration waves effectively.