|Budget Amount *help
¥2,200,000 (Direct Cost: ¥2,200,000)
Fiscal Year 1996: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 1995: ¥1,700,000 (Direct Cost: ¥1,700,000)
Methanol, ethanol, and alcohol blend fuels including them as main component are expected as feasible alternative fuels.Alcohol blend fuels that include components forming rich mixture or mixture beyond the upper flammable limit have advantages in safety storage since the possibility of forming flammable mixture layr on the liquid surface is usually smaller than that for pure methanol or ethanol. However, in transient processes or in large containers, the possibilities of thick flammable layr still remain. Therefore, it is important to understand explosion characteristics. In this study, explosion safety of storage of methanol/gasoline blend fuels was explored by using small vessels. The fuel was provided so as to cover the bottom, and for various sets of initial temperature, vaporized time, spark gap height, the mixture was ignited. In the former half of the projeic term, M100, M97, M95 including commercial white gasoline were examined, and in the latter half, M95, M90, and M85 including model gasoline consisting of seven pure components were examined. Several typical patterns of pressure fluctuation were identified. The contours of the maximum pressure rise and the range of explosion were plotted in the spark gap height-vaporized time plane. From the plots it was inferred that below 20ﾟC,where methanol-air mixtures in equilibrium are lean, within small gasoline content the range of explosion and maximum pressure rise increase with the content at first, and that except this region the exploded range is shrunk and the maximum pressure rise decreases with the increase of gasoline content. The observed maximum pressure rise is at least 1 atm and in usual cases it reaches 3 to 8 atms. These results indicate that if the ignition source is not excluded completely, the container to bear with expected pressure rise, or the increase of gasoline content should be necessary.