238 / 2018-05-05 17:56:08

Temperature Influence on Peak Explosion Pressure and Flame Propagation Speed during Explosions of Flammable Gases

Peak explosion pressure,temperature,methane-air explosion,Deflagration index,spheical outward flame propagation,maximum flame propagation speed

矿山职业健康与环境安全 > 防爆炸

This work aimed to experimentally evaluate temperature influence on explosion characteristics of methane in air . The explosion characteristics were performed in a 20-L spherical explosion tank that a circular view port with a diameter of 110 mm was set. All experiments were conducted at different temperature (273-373K) and at ambient pressure, with a relative humidity range from 52 to 73%. The peak explosion pressure (Pmax), maximum pressure rise rate ((dp/dt)max), and gas deflagration index (KG) were observed and analyzed. The flame propagation behavior in the initial stage was recorded using a high-speed camera. The spherical outward flame front was determined on the basis of a canny method, from which the maximum flame propagation speed (Sn) of pure methane was calculated. At constant initial pressure and composition, the Pmax decrease with the increase of temperature. Furthermore, the (dp/dt)max and KG are slightly influenced by the initial temperature. And when the initial temperature rises, the Sn increases for the fuel-lean and stoichiometric range of the methane-air mixture. For methane-air mixture concentrations in fuel-rich, the Sn slightly decreases with increasing temperature.