Aim To study fuel dispersion in fuel air explosive(FAE) and computational ways of fuel dispersion velocity in the near area. Methods\ The dispersion process of fuel in FAE was analyzed by the use of results measured ...Aim To study fuel dispersion in fuel air explosive(FAE) and computational ways of fuel dispersion velocity in the near area. Methods\ The dispersion process of fuel in FAE was analyzed by the use of results measured with KODAK EKTAPRO EM Motion Analyzer and setting up mechanical models. Results\ Computational methods for fuel dispersion velocity in the acceleration stage is given and taken as a base for the study of fuel dispersion in the intermediate and the far area. Conclusion\ When the fuel flow velocity is higher than that of the explosion gas in the center cavity, the fuel divides with the explosion gas and its velocity of flow reaches a maximum. The acceleration stage ends at that time. The fuel dispersion velocity at this time is the initial conditions for numeral analyses of dispersion process in the intermediate and far areas.展开更多
An experimental system was setup to study the pressure field of unconfined vapor cloud explosions. The semi-spherical vapor clouds were formed by slotted 0.02mm polyethylene film. In the center of the cloud was an ign...An experimental system was setup to study the pressure field of unconfined vapor cloud explosions. The semi-spherical vapor clouds were formed by slotted 0.02mm polyethylene film. In the center of the cloud was an ignition electrode that met ISO6164 'Explosion Protection System' and NFPA68 'Guide for Venting of Deflagrations'. A data-acquisition system, with dynamic responding time less than 0.001s with 0.5% accuracy, recorded the pressure-time diagram of acetylene-air mixture explosion with stoichiometrical ratio. The initial cloud diameters varied from 60 cm to 300 cm. Based on the analysis of experimental data, the quantitative relationship is obtained for the cloud explosion pressure, the cloud radius and the distance from ignition point. Present results provide a useful way to evaluate the building damage caused by unconfined vapor cloud explosions and to determine the indispensable explosion grade in the application of multi-energy model.展开更多
文摘Aim To study fuel dispersion in fuel air explosive(FAE) and computational ways of fuel dispersion velocity in the near area. Methods\ The dispersion process of fuel in FAE was analyzed by the use of results measured with KODAK EKTAPRO EM Motion Analyzer and setting up mechanical models. Results\ Computational methods for fuel dispersion velocity in the acceleration stage is given and taken as a base for the study of fuel dispersion in the intermediate and the far area. Conclusion\ When the fuel flow velocity is higher than that of the explosion gas in the center cavity, the fuel divides with the explosion gas and its velocity of flow reaches a maximum. The acceleration stage ends at that time. The fuel dispersion velocity at this time is the initial conditions for numeral analyses of dispersion process in the intermediate and far areas.
基金Supported by the National Natural Science Foundation of China(No. 50076006).
文摘An experimental system was setup to study the pressure field of unconfined vapor cloud explosions. The semi-spherical vapor clouds were formed by slotted 0.02mm polyethylene film. In the center of the cloud was an ignition electrode that met ISO6164 'Explosion Protection System' and NFPA68 'Guide for Venting of Deflagrations'. A data-acquisition system, with dynamic responding time less than 0.001s with 0.5% accuracy, recorded the pressure-time diagram of acetylene-air mixture explosion with stoichiometrical ratio. The initial cloud diameters varied from 60 cm to 300 cm. Based on the analysis of experimental data, the quantitative relationship is obtained for the cloud explosion pressure, the cloud radius and the distance from ignition point. Present results provide a useful way to evaluate the building damage caused by unconfined vapor cloud explosions and to determine the indispensable explosion grade in the application of multi-energy model.
