为了解火灾环境下含炸药结构的热响应行为，针对其涉及的主要传热学问题，建立了池火灾火焰温升数值模型，碳/酚醛烧蚀层高温热解吸热数值模型，空气夹层复合传热数值模型，以及炸药受热分解放热数值模型。用所建数值模型，计算并获得...为了解火灾环境下含炸药结构的热响应行为，针对其涉及的主要传热学问题，建立了池火灾火焰温升数值模型，碳/酚醛烧蚀层高温热解吸热数值模型，空气夹层复合传热数值模型，以及炸药受热分解放热数值模型。用所建数值模型，计算并获得了含炸药结构在不同温升条件下（恒定值1073 K、1273 K 及本研究所提的火焰实测温升曲线）、不同火焰辐射率（0．1～0．9）和不同空气夹层间壳体表面辐射率（0．1～0．9）下的温度响应和热点火延滞时间。结果表明：火烧30 min 情况下，火焰温度为1273 K 时，内部炸药在28．92 min 已经发生热点火现象。火焰温度为1073 K 和实测温升曲线时，内部炸药最高温度分别为448 K 和535 K。火焰辐射率从0．9降低到0．1时，内部炸药最高温度由535．4 K 降低到344．6 K，热点火延滞时间由1917 s 增加到3520 s。空气夹层间壳体表面辐射率由0．9降低到0．1时，内部炸药最高温度由535．4 K 降低到329．0 K，热点火延滞时间由1917 s 增加到3739 s。展开更多
In order to improve the quality of laneways and tunnel excavation by drilling and blasting and by making effective use of explosive energy, a model experiment of rock blasting with a single borehole and a double free-...In order to improve the quality of laneways and tunnel excavation by drilling and blasting and by making effective use of explosive energy, a model experiment of rock blasting with a single borehole and a double free-surface was performed with the objective of studying the effect of parameters such as charge structure, free-surface and rock compressive strength on rock blasting.The model experiments indicate that:1) the smaller the rock compressive strength and density, the more distinctive the cavity expanding action by blasting;2) the powder factor in an air-decoupling charge structure is larger than that in a coupling charge structure, i.e., the explosive energy in an air-decoupling charge structure transferred to the rocks is less than that in a coupling charge structure;3) a free-surface improves the utilizations of explosive energy;4) an air-decoupling charge structure helps to maintain the integrity and stability of wall rock in controlled perimeter blasting, such as in roadways and tunnel excavation by drilling and blasting.展开更多
文摘为了解火灾环境下含炸药结构的热响应行为，针对其涉及的主要传热学问题，建立了池火灾火焰温升数值模型，碳/酚醛烧蚀层高温热解吸热数值模型，空气夹层复合传热数值模型，以及炸药受热分解放热数值模型。用所建数值模型，计算并获得了含炸药结构在不同温升条件下（恒定值1073 K、1273 K 及本研究所提的火焰实测温升曲线）、不同火焰辐射率（0．1～0．9）和不同空气夹层间壳体表面辐射率（0．1～0．9）下的温度响应和热点火延滞时间。结果表明：火烧30 min 情况下，火焰温度为1273 K 时，内部炸药在28．92 min 已经发生热点火现象。火焰温度为1073 K 和实测温升曲线时，内部炸药最高温度分别为448 K 和535 K。火焰辐射率从0．9降低到0．1时，内部炸药最高温度由535．4 K 降低到344．6 K，热点火延滞时间由1917 s 增加到3520 s。空气夹层间壳体表面辐射率由0．9降低到0．1时，内部炸药最高温度由535．4 K 降低到329．0 K，热点火延滞时间由1917 s 增加到3739 s。
基金Natural Science Foundation of Anhui Province of China (1808085QA06)Scientifific Research Foundation of the Education Department of Anhui Province of China (KJ2018A0090)+1 种基金Fund of Anhui Province of China (2019B355)Graduate Innovation Fund Project of Anhui University of Science and Technology(2021CX2027)。
文摘In order to improve the quality of laneways and tunnel excavation by drilling and blasting and by making effective use of explosive energy, a model experiment of rock blasting with a single borehole and a double free-surface was performed with the objective of studying the effect of parameters such as charge structure, free-surface and rock compressive strength on rock blasting.The model experiments indicate that:1) the smaller the rock compressive strength and density, the more distinctive the cavity expanding action by blasting;2) the powder factor in an air-decoupling charge structure is larger than that in a coupling charge structure, i.e., the explosive energy in an air-decoupling charge structure transferred to the rocks is less than that in a coupling charge structure;3) a free-surface improves the utilizations of explosive energy;4) an air-decoupling charge structure helps to maintain the integrity and stability of wall rock in controlled perimeter blasting, such as in roadways and tunnel excavation by drilling and blasting.
