(3) The change of laws of maximum explosion pressure, maximum
rate of pressure rise and blast-wave peak overpressure
of 100 nm aluminum powders with concentration are similar
to those of 75 lm aluminum powders, and the effect of
particle sizes on them is smaller. The conclusions obtained
in horizontal pipes are similar to those in 20 L spheroid.
(4) The most violent concentration of 100 nm aluminum-powder
explosion in pipes is about 0.4 kg/m3, which is lower
than 0.8 kg/m3 of 75 lm aluminum powder, and the maximum
explosion pressure, maximum rate of pressure rise
and blast-wave peak overpressure of 100 nm aluminum
powders are much higher than 75 lm aluminum powders
under the same concentration. So the 100 nm aluminum
powder is more easily exploded, and more harm will be produced
than 75 lm aluminum powder. The main reasons are
that the particle sizes of nano-aluminum powders are smaller
than common ones, the specific surface area of particle is
larger, the oxygen adsorptions are many more, and the particle
burning is more sufficient.