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.

Natural gas supply apparatus

Abstract: Apparatus for supplying natural gas fuel to heat the boilers of an ocean-going tanker for the transport of liquefied natural gas (LNG) comprises a compressor having an inlet communicating with the ullage space of at least one LNG storage tank and an outlet communicating with a conduit leading from the compressor to fuel burners associated with the boilers, and a forced LNG vaporiser having an inlet communicating with a liquid storage region of the said tank and an outlet communicating with the same or a different conduit leading to fuel burners associated with the boilers.

Passive propellant management system

Abstract: A passive propellant management system for a spacecraft liquid propellant tank (1) comprises several preferably V-shaped channels (2) which communicate liquid propellant from regions within the tank (1) to an outlet port (8), which expels liquid propellant but not pressurant gas. A liquid/bubble chamber assembly (9) couples the channels (2) with the outlet port (8). The channels (2) comprise relatively open portions (11) and relatively closed portions (10). In the relatively open portions (11), liquid is retained in a gap (12) between open ends of the V channels (2) and the inner wall of the tank (1). In the relatively closed portions (10), a screen, mesh or perforated plate (14) covers the open end of the V channels (2), intermediate the V channels (2) and the inner wall of the tank (1). The placement of the relatively open and closed portions (11, 10, respectively) is intentionally preselected based upon mission requirements. Where pressurant gas ullage is expected to be present, e.g., during periods of high g, relatively open portions (11) are used. Where liquid propellant is expected to be present, e.g., during periods of relatively low g, relatively closed portions (10) are used. The liquid/bubble chamber assembly (9) comprises a liquid trap (27) and bubble trap (28), which operate synergistically with each other and with the channels (2) to provide optimum liquid flow during all phases of the spacecraft mission.

Turbo compressor for use in OBIGGS application

Abstract: An on-board inert gas generating system (OBIGGS) uses a turbine in order to recover the energy of compression of the nitrogen-enriched product gas. This energy is transferred, through a shaft, to the compressor, which supplies compressed air to the separation membrane. Unlike conventional systems, where there is no means for recovering the energy of the compressed nitrogen enriched product air, the present system provides a cooled nitrogen-enriched gas to be supplied to a fuel tank ullage without losing the energy stored in the compressed nitrogen-enriched product gas.

Investigation of Tank Pressurization and Pressure Control—Part II: Numerical Modeling

Abstract: A multizone model is used to predict both the self-pressurization and pressure control behavior of a ground-based experiment. The multizone model couples a finite element heat conduction model of the tank wall to the bulk conservation equations in the ullage and the liquid. Comparisons are made to the experimental data presented in a companion paper. Results suggest that the multizone model can predict self-pressurization behavior over a variety of test conditions. The model is also used to predict the pressure control behavior when a subcooled axial mixing jet is used to thermally destratify and cool the bulk liquid. For fast jet speeds, the multizone model does a reasonably predict the pressure collapse behavior. Comparisons were also made between the data and a homogeneous thermodynamic model. These comparisons highlight the deficiencies of the homogeneous modeling approach.