WHy do you use ventholes on the oxidizer tank?

[rock]

Hello

Been reading an assembly instruction for a scyripper hybrid rocket engine, but one of the things i cant understand is the need for vent holes in the oxidizer tank.

I get the picture if the rocket in question would use gas condensated by cooling, such as liquid oxygen in the case of the space shuttle (when heat is being taken from the surroundings), but as far as i know, the common hybrid rocket uses pressure condensated N2O, so there should be no need to vent the gas, as the pressure in the tank wont increase on its own.

Ideas?

 

[plano-doug]

Hello

Been reading an assembly instruction for a scyripper hybrid rocket engine, but one of the things i cant understand is the need for vent holes in the oxidizer tank.

I get the picture if the rocket in question would use gas condensated by cooling, such as liquid oxygen in the case of the space shuttle (when heat is being taken from the surroundings), but as far as i know, the common hybrid rocket uses pressure condensated N2O, so there should be no need to vent the gas, as the pressure in the tank wont increase on its own.

Ideas?

Two things. When the tank is being filled with liquid N2O, the air in the tank must be allowed to escape. Plus, once the tank is full, the escaping liquid creates a visible cloud telling the operators that it's ready to launch.


Doug

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