When I casually think of an explosion I think of a rapidly expanding sphere of gases. It turns out this is rarely the case. An explosion propagates from the point of detonation along a (typically expanding) “front”. Because the pressure at the front is much greater than both ahead and behind it the gases produced, which are behind the front, expand in a direction away from the front. This video from Ry demonstrates that. The exploding targets are 7″ x 7″ x 1.375″. The gases expand into the axis parallel to the 1.375″ dimension. Until this video we did not realize this.
Whatever shape of the explosive and whereever the point(s) of detonation are affects the directions of the explosion. This is used to great effect in the Rocket Propelled Grenade (RPG) which can, with a rather small amount of explosives, penetrate over 30 inches of renenforced concrete, or a foot of steel.
That is COOL. The audio is great also– instructive. Hollywood should take a lesson or two from it. Most of their gunshot sounds don’t come close to reality, which is distracting for anyone familiar with reality.
I’m not trying to sound all-knowing, but I’m surprised you weren’t aware of shaped charges. The military uses shaped charges from 20mm grenades to 120mm tank rounds. The main charge pushes a copper cone inside out and forms a jet of copper that travels REALLY fast and penetrates LOTS of armor.
Cool stuff.
I have been aware of shaped charges for many, many years. It was just that with a charge that was the shape and size of a book we were surprised at how directional it was.