Showing papers on "Ullage published in 1979"

Propellant injection for MPD thrusters

Abstract: The propellant gas for a pulsed self-field MPD thruster must be supplied by a valve which will necessarily be separated from the thruster injectors by some ullage volume. A model and experimental data are presented showing the effect of the ullage volume on the propellant pulse shape, along with a discussion of the proper location for the propellant flow choke point(s). Prospective MPD pulse valves are surveyed and the performance of two solenoid valves, one with a pulse length less than 2 milliseconds, is included. Pulse shape data is presented for a thruster specially modified to reduce the ullage volume.

Anti-static coating on ullage tapes comprising carbon black derived from a rich acetylene flame

Abstract: A static electric charge removal of dispersal coating for ullage tapes having an outer polymeric surface. The coating is formed of carbon black and is applied to the polymeric surface of the ullage tape to disperse therefrom any static electric charge which may be generated thereon when used for measurement purposes in large tanks which can build up a high static charge therein. The carbon black coating is preferably acetylene black formed on the tape and simultaneously anchored thereto by passing the tape near a fuel rich acetylene flame. Any excess coating which is not anchored to the tape can be removed by wiping or other similar operation. The method of this invention can be used to apply an acetylene black coating to polymeric items such as fluorocarbon wire, tape, or other forms which can be passed in close proximity to a fuel rich acetylene flame.

Assembly for the transport of fuel elements

Abstract: An assembly for the transport and storage of nuclear fuel elements comprises a transport flask and a holder for fuel elements which fits within the flask. The assembly has self regulating ullage means which may comprise a plurality of eleongate reservoirs so designed that liquid is maintained in all the reservoirs when the assembly is in either the orientation used to load fuel elements into the assembly or in the orientation used to transport the fuel elements.

Portable device for determining physical qualities of pressurized container contents

Abstract: A portable device is provided for determining the physical qualities, such as amount, ullage, temperature, etc., of liquids in closed tanks containing the liquid and vapors of the liquid and/or an inert gas above the liquid without lowering the pressure or allowing the pressurizing gas or vapors to escape to the atmosphere.

Relationship of pressure to temperature rise in overfilled cylinders

Abstract: Mild steel pressure vessels containing uranium hexafluoride are heated in 96-inch diameter autoclaves to allow the feed material to enter the gaseous diffusion process equipment for enrichment in the uranium 235 isotope. For purposes of safety analysis it is necessary to establish the ability of the instrumentation to shut off the steam supply to the autoclave prior to cylinder rupture if the cylinder has been overfilled. To make this determination requires estimates of the rate of change of pressure with respect to change of temperature at constant volume as a function of the temperature at which the ullage disappears. The paper presents the calculations for the estimation of this rate of change for liquid uranium hexafluoride using the ratio of the coefficients of expansion and compressibility using empirical liquid density data and the Eyring equation of state for liquids. 5 figs. (MB)

Preflight status of the External Tank portion of the Space Shuttle Main Propulsion System

Abstract: The development progress of the External Tank (ET) of the Shuttle Main Propulsion System (MPS) is described. 87% of ET propulsion components have satisfactorily completed qualification tests in preparation for the first Shuttle flight and their performance has been verified in the Main Propulsion Test Article (MPTA) firings of up to 100 seconds duration. The design changes in the LH2 tank pressurant diffuser, the LO2 feed system, and the ground test LO2 tank are discussed. Propellant loading information from MPTA tests may be used to predict loading operations and performance at KSC and VAFB, while ullage pressure profiles and boil-off rates during loading, chilldown rates, and final bulk density data have been obtained with geyser suppression evaluated and loading procedures established and verified. The MPTA test experience provided data to evaluate pressurization system and ET to Orbiter interface propellant performance noting thus that the fluid interface requirements will be satisfied for the first Shuttle flight. The Intertank inerting system was found to be effective in minimizing hazardous gas mixtures and full scale separation tests of the ET to Ground Umbilical Carrier Plate system were successfully completed.