In order to study the shock wave propagation law of coal
dust explosion
in complex structures, the diagonal pipe network model was established
by using computational fluid dynamics software, and the numerical
simulation of the coal dust explosion in the diagonal branch was carried
out. The change law of the shock wave and its attenuation at the corner
were analyzed. The results show that the pressure change process of
coal dust explosion can be divided into three stages, namely, the
stage where the pressure value at the ignition point is relatively
high, the stage where the pressure value on both sides of the ignition
source is maximum, and the stage where the pressure value at the shock
wavefront is relatively maximum; the overpressure of the shock wave
decays at the bifurcation point, and the larger the bifurcation angle,
the greater the pressure attenuation amplitude. For the same bifurcation
angle, the greater the initial pressure at the monitoring point, the
greater its attenuation amplitude. Multiple regression fitting on
the shock wave pressure values was performed before and after turning,
and the function relationship between the shock wave pressure attenuation
coefficient and the initial pressure, as well as different turning
angles, was obtained. The fitting results can be used as a formula
for calculating the ventilation network during the disaster process,
which has theoretical significance for evaluating the consequences
of coal dust explosion accidents.