Aww... too bad... I thought those characters were supposed to give a hint at the tank's role
Judging by the appearance of these things, they don't appear to be intended to be accurate. Short barrel, placed in box of fours in a crude fashion, no targetting mechanism.
So they can't be AA guns. AA guns need to be accurate
I don't think they're flame throwers either. If you want a flame thrower with huge coverage you just need a single barrel and swing it around. Besides, 8 flame thrower barrels would seriously overheat the boxes
They could be... small machine guns to provide cover fire against infantry
My guess though is that it's an experimental design for shooting down incoming missiles and rockets, but was unsuccessful so it ended up becoming a display piece.
It's hard to aim a gun at a missile even if you're gun is accurate, so the solution would be to have many guns put together to give high volume of fire and high total fire rate (fire rate of all guns combined) and shoot them all in the general direction of the missile, one of them's gotta hit. Because it relies on volume, fire rate, and chance, a good targetting device is not important.
And because a missile only spends short time reaching your tank, you don't need to fire at it for extended periods of time, so less ammo is required. The ammo are probably kept within the box
I think the biggest problem would be that the guns are fixed to the turret so it turns too slowly in response to missiles. It could make sense if your turret is already pointed at some target, then that target suddenly shoots a rocket at you so you immediately light up your anti-missile guns and try to shoot it down.