Ullage

About: Ullage is a research topic. Over the lifetime, 501 publications have been published within this topic receiving 4704 citations. The topic is also known as: headspace.

Ullage opening spillage prevention system

Abstract: A system for preventing spillage or overflow of liquid cargo through the ullage openings of cargo tanks of a tanker. An elongated guide is provided in the expansion trunk of each of the cargo tanks, the guide being characterized by an open framework which mounts a float for movement toward the ullage opening when the liquid cargo rises in the tank. The float is engageable with a seat adjacent the opening to seal off the opening and prevent cargo spillage occasioned by inadvertent overfilling. The open framework of the guide permits the ullage opening to still be used to insert a probing element into the cargo tank, the guide preferably being inclined from the vertical for this purpose. Conduits are also provided to convey overflow cargo to empty cargo spaces.

Liquid oxygen sloshing in Space Shuttle External Tank

Abstract: This paper describes a numerical simulation of the hydrodynamics within the liquid oxygen tank of the Space Shuttle External Tank during liftoff. Before liftoff, the tank is filled with liquid oxygen (LOX) to approximately 97 percent with the other 3 percent containing gaseous oxygen (GOX) and helium. During liftoff, LOX is drained from the bottom of the tank, and GOX is pumped into the tank's ullage volume. There is a delay of several seconds before the GOX reaches the tank which causes the ullage pressure to decrease for several seconds after liftoff; this pressure 'slump' is a common phenomenon in rocket propulsion. When four slosh baffles were removed from the tank, the ullage gas pressure dropped more rapidly than in all previous flights. The purpose of this analysis was to determine whether the removal of the baffles could have caused the increased pressure 'slump' by changing the LOX surface dynamics. The results show that the LOX surface undergoes very high vertical accelerations (up to 5 g) and, therefore, splashing almost certainly occurs. The number of baffles does not affect the surface if the structural motion is assumed; but, the number of baffles may affect the structural motion of the tank.

Hydrodynamic ram mitigating fuel cell structure

Abstract: A system and method to mitigate the effect of hydrodynamic ram. The system including a chamber adapted to receive fluid and a core disposed within the chamber. A plurality of columns extend through the core and a plurality of orifices extend through the thickness of the columns. The method includes channeling a portion of a vapor bubble to an ullage space disposed within the chamber with the plurality of columns and changing the fluid state of the vapor bubble with a plurality of orifices extending through the thickness of the plurality of columns.

System and method for reduced flammability of an aircraft fuel system

Abstract: Disclosed is a method for controlling the flammability of fuel vapors in an aircraft main fuel tank that is located in whole or in part in the fuselage contour The method comprises a fuel system architecture and fuel consumption sequencing maintaining liquid fuel in said main tanks during all normal operations Ceasing the withdrawal of fuel from the main tank when the fuel reaches a predetermined level thereby limiting the volume and flammability exposure time of the fuel vapor ullage Once the predetermined level is met the fuel is supplied from wing tanks throughout the remainder of the mission The predetermined main tank fuel level at which wing tank fuel begins to be consumed is determined by the aircraft flight reserves fuel volume stored in the main tank as well as the amount necessary to continuously submerge the main tank fuel pumps during the entire mission