What is ullage?

The extra volume of gas above the propellant in a tank

The volume of propellant stored inside a tank neglecting its empty volume

The ratio of the volume of extra gas to that of the propellant after 50% of the propellant has been consumed

The ratio of the volume of the propellant to that of the extra gas after 50% of the propellant has been consumed

Correct Answer : The extra volume of gas above the propellant in a tank

Explanation : Ullage is the extra volume of gas that lies above the propellant in a sealed tank. It is necessary for this extra volume to exist as it takes into account the thermal expansion of the propellant fluid.

Recently Updated in Rocket Propulsion Questions

Which of the following is not a property of the main liquid oxygen valve?

Low pressure

High pressure

Cryogenic

Reusable ball valve

Correct Answer : Option (A) : Low pressure

Explanation : Main liquid oxygen valves are under high pressure. Since liquid oxygen easily evaporates under normal atmospheric conditions, they are kept in cryogenic tanks. These valves also make use of reusable ball valves.

German antiaircraft missile Wasserfall used four of which of the following valves?

Latch valves

Burst diaphragm

Isolation valves

Drainage valves

Correct Answer : Option (B) : Burst diaphragm

Explanation : Burst diaphragm is used in the German missile Wasserfall. It actually used 4 of such burst disks.

Which of the following valves help in controlling gas pressures?

Latch valves

Isolation valves

Burst diaphragm

Pressure regulator

Correct Answer : Option (D) : Pressure regulator

Explanation : Pressure regulator, as the name mentions, helps in regulating or controlling gas pressure. Other valves serve different purposes, like maintaining the flow until a pressure differential (burst diaphragm) or for isolation of a particular flow region.