from world of warships wiki
Detonation in World of Warships is caused by the ignition of at least one of the Magazine modules of the ship. Historically, they are where the powder charges and ammunition for the main artillery are stored. In game, sufficient damage that causes one magazine to explode results in the destruction of the entire ship regardless of how much health it has remaining.
The Armor Viewer in the Port Screen can be used to show the locations of the magazines, such as the ones on the Admiral Graf Spee.
To cause a detonation to occur, damage needs to be dealt to the magazines, which are found underneath the primary turrets and/or primary artillery. In other words ships, like Novik, that have non-enclosed rifles behind blast shields have magazines located beneath the deck. Damage to the magazines can be caused by penetrating damage from direct hits by armor-piercing shells, splash damage from high explosive shells, or even torpedoes if they hit close enough to a magazine below the waterline.
It should be noted that there is no situation in the game that warrants a 100% detonation chance. With that said, certain actions or choices will increase the probability of Detonation; a few of them are highlighted below:
As stated above, taking damage to the magazines will increase the chances of detonation occurring. When a magazine loses all of its hit-points, the chance of detonation will increase to its maximum native value. Note that this is still below 100%. Each ship has its own metric for calculating detonation chance based upon magazine hit-pool.
Therefore, by this logic, aircraft carriers can never be detonated since they have no magazine.
Each ship has its own armor value for the magazines, therefore ships with thinner magazine armor will inherently have a higher detonation chance.
Mounting either India X-Ray () or Juliet Whiskey Unaone () signal flags will increase magazine detonation chance.
As stated above, the occurrence of a magazine detonation will also detonate the entire ship; resulting in a complete depletion of the ship’s health pool. To further emphasize: even the detonation of one magazine is enough to cause an explosion of the entire ship.
The chance of detonation can be decreased in three ways:
Mount Magazine Modifications 1 as the Upgrade for Slot 1. This will decrease the chance of magazine detonation by 70%.
Mount the Juliet Charlie signal flag; this will decrease the chance of magazine detonation by 100%. In other words: the magazine will not detonate if this signal is mounted on the ship.
Another way to reduce the chance is by armor angling. This tactic consists of pointing the bow of the ship at (or angled towards) towards the enemy. Certain ships can similarly angle point their sterns towards the enemy and prevent detonations as well. Many detonations are caused by presenting the flat side of the ship (aka "sailing broadside") to the enemy; angling a ship will help reduce this possibility. (Angling can also greatly reduce the chance of citadel damage. This is why players will notice when shooting at or aiming at a ship it will turn in or away reducing the angle and ability to detonate and/or hit the citadel.)
Its been some time back well i think back in the closed beta archives one of the devs hoped on and exsplaned it more detail. Your magazine diffrent for ever ship and it location too. Its location and Hp and chance of detionation is only server side if i do recall. Yes RNG has 100% chance in this feature in the game but it can be medigated so it does not happen often. I like its in the game it a fun thing to do to some one and i laugh my [edited]of once i get detinated because of the chances to do so are rare.