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.

Liquid Hydrogen Zero‐Boiloff Testing and Analysis for Long‐Term Orbital Storage

Abstract: Advancement of cryocooler and passive insulation technologies in recent years has improved the prospects for zero‐boiloff (ZBO) storage of cryogenic fluids The ZBO concept involves the use of a cryocooler/radiator system to balance storage system incoming and extracted energy such that zero boiloff (no venting) occurs A large‐scale demonstration of the ZBO concept was conducted using the Marshall Space Flight Center (MSFC) multipurpose hydrogen test bed (MHTB) along with a commercial cryocooler unit The liquid hydrogen (LH2) was withdrawn from the tank, passed through the cryocooler heat exchanger, and then the chilled liquid was sprayed back into the tank through a spray bar The spray bar recirculation system was designed to provide destratification independent of ullage and liquid positions in a zero‐gravity environment The insulated MHTB tank, combined with the vacuum chamber conditions, enabled orbital storage simulation ZBO was demonstrated for fill levels of 95%, 50%, and 25% At each fill level, a steady‐state boiloff test was performed prior to operating the cryocooler to establish the baseline heat leak Control system logic based on real‐time thermal data and ullage pressure response was implemented to automatically provide a constant tank pressure A comparison of test data and analytical results is presented in this paper

Ullage volume sensor

Abstract: A device for measuring the free space in a tank is based on a second order mass spring system in which the spring is formed from the unknown volume (Vullage) of gas above the liquid in the tank and the mass is formed by the piston (3a). The resonant frequency of the system is used to determine the ullage volume above the liquid. This information is used to regulate the filling rate of the tank, said rate being proportional to the ullage volume.

Closed vapor control system for the ullage spaces of an oil tanker, including during a continuous maintenance of an ullage space underpressure

Abstract: Vapors, typically volatile organic compounds, emitted from a vaporizable liquid, typically oil, that is within a tank, typically a ship's tank, are (i) compressed, and (ii) stored in a reservoir that is closed to the atmosphere. The (i) compression typically transpires in and by a series/parallel array of pumps, rotary or reciprocating compressors, to a storage pressure of 150+ PSIA. The several million cubic feet ullage volume of a typical 200,000 ton oil tanker is typically compressed over a few days during and/or after loading, and stored in a typically spherical gas storage tank of some 10-20 feet in diameter. Stored gases are returned to the ullage spaces during offloading of the oil tanks in a closed system. This emission control by vapor recovery is interoperative with related systems and methods (i) to avoid spillage of oil due to the rupture of a ship's tank, and/or (ii) to make and maintain a mixture of gases and vapors within the tank's ullage space to be non-explosive and non-flammable. The first parallel system creates and dynamically maintains a partial vacuum in the tank's ullage space--even as all gases and vapors that are evacuated in order to do so are processed into the emission control system. The second parallel system injects an inert gas into the ullage spaces above the oil in the tanks--even though some of this inert gas becomes part of the compressed and stored gas and vapor mixture, rendering this compressed mixture itself non-explosive and non-flammable.

Transport-launching pack mainly for torpedo-type weapon

Abstract: FIELD: transport-launching packs for torpedoes. ^ SUBSTANCE: the transport=torpedo pack has a sealed body including a cylindrical shell with a destructible front cover and a domed bottom. The cylindrical shell is partially overlapped by the central cowling enveloping it with formation of a cavity that is filled with heat insulation. The bottom is provided with a shell enveloping the body with formation of a cavity that is filled with heat insulation. The sealed body, cylindrical cowling and the bottom shell are made of a composite material. The transport-launching pack also has a gas source for torpedo launch, torpedo retaining device, retaining device unlocking aid, electrical connectors of the electric coupling of the ship launch control system to the transport-launching pack, piling aid, temperature control system including a heating means, cooling aid and temperature-sensitive elements. A ullage motor is used in the transport-launching pack as a torpedo launch gas source. The sealed body of the transport-launching pack is made in the form of successively installed detachably joined to one another sections for placement of the torpedo, ullage motor, equipment of the cooling means respectively. The last section is also detachably joined to the bottom. The section for placement of the torpedo is made for sealing of its volume during operation of the ullage motor. The body of this section is made with inner centering guide components for the torpedo. The body of the section for placement of the torpedo near the front end face is made with an inside obturator in the form of a circular support. A collector ring is installed in the tail part of this section close to the cylindrical shell. The collector ring communicates with the section volume for placement of the torpedo by means of longitudinal ducts made in the centering guide components. The torpedo retaining aid is installed on the flange of the front end face of the body of the collector ring, and a seaped detachable partition is installed on the rear end face through a tight seal. The ullage motor is installed in cantilever on the partition, it is positioned inside the respective section. The cap of the ullage motor is passed through a hole in the partition, and the outlets of the ullage motor communicate with the volume of the section for placement of the torpedo. The unlocking aid of the torpedo retaining device includes a piston with a rod which are installed in the cap of the ullage motor for engagement of the rod tail end with the torpedo retaining device. The heating means has heating elements that are moulded in the material of the cylindrical shell in the area of the body section for placement of the torpedo. The equipment of the cooling means is installed in the respective section of the body of the transport-launching pack, and through an extended hollow component it communicates with the collector ring. The equipment of the cooling means includes an impeller for circulation of the refrigerant. The pilling aid is made in the form of aligned supports with engagement components for engagement with the mating engagement components of the launcher and/or supports of other transport-launching packs. ^ EFFECT: expanded possibility of torpedo use in various climatic zones. ^ 8 cl, 3 dwg