Abstract:
A liquid-propellant tank for a spacecraft is symmetric about a longitudinal axis, and has a transverse partition (15) and a truncated conical partition (16), which divide the interior of the tank into a remote chamber (20), a proximate peripheral chamber (21) and a proximate axial chamber (22). Communication between the remote chamber (20) and the proximate peripheral chamber (21) is provided by a port structure (23), and communication between the proximate peripheral chamber (21) and the proximate axial chamber (22) is provided by a port structure (24). As liquid propellant is withdrawn from the tank, pressurant gas in the remote chamber (20) causes liquid propellant to pass from the remote chamber (20) into the proximate peripheral chamber (21) to replace liquid propellant thereby forced from the proximate peripheral chamber (21) into the proximate axial chamber (22), which replaces the liquid propellant withdrawn from the tank. Emptying of the three chambers in sequence limits the extent of migration of liquid propellant within the tank, thereby minimizing the effects of liquid-propellant migration on attitude stability of the spacecraft.
Abstract:
In a liquid storage tank 10 for use on a spacecraft, a transfer apparatus 15 (comprising gathering vanes 33, an elongate array of fins 32, and a sponge structure formed from panels 31) functions to transfer liquid from the inner surface of the tank 10 to the vicinity of an outlet line 40. A screen 23 is disposed between the panels 31 and the outlet line 40. When wetted with liquid, the screen 23 prevents gas and/or vapor in the tank 10 from passing to the outlet line 40. A perforated plate 22 disposed between the screen 23 and the outlet line 40 causes liquid to pass from the tank 10 to the outlet line 40 in a regular and generally unbroken flow.
Abstract:
In a tank 10 for cryogenic liquid to be used in a low-gravity environment (e.g., on a space vehicle), a liquid transfer apparatus 15 (which comprises an elongate array of fins 32 and a sponge structure formed from panels 31) functions to transfer cryogenic liquid from the interior of the tank 10 to a bowl structure 20 defining a reservoir region adjacent an outlet of the tank 10. A perforated plate 22 disposed between the sponge structure and the outlet of the tank 10 causes cryogenic liquid to pass through the outlet into an outlet line 40 in a regular and generally unbroken flow. To prevent any substantial amount of heat transfer into the reservoir region of the tank 10, the bowl structure 20 is separated from the inner surface of the tank 10 by a capillary distance in order to provide a thermally insulating space therebetween. A well for cryogenic fluid, which is in communication with the thermally insulating space between the bowl structure 20 and the inner surface of the tank 10, is formed around an outlet duct 21 leading from the bowl structure 20 in order to prevent any significant transfer of heat into cryogenic liquid that is being withdrawn from the tank 10 through the outlet duct 21.
Abstract:
In a liquid-propellant management system for providing substantially gas-free liquid propellant to thrusters of a space vehicle, a storage tank (10) has an opening (11) through which liquid propellant is delivered via a line (13) to the thrusters. A trap (14) is secured within the tank (10) adjacent the opening (11). and an exit port (15) of the trap (14) is aligned with the opening (11) of the tank (10). A liner (16) is secured inside the trap(14) to define a volume between an interior surface portion of the trap (14) and the liner (16), which volume communicates via the exit port (15) and the opening (11) with the line (13). Liquid propellant enters into the trap (14) through an inlet window screen (27), and passes through porous windows (28) in the liner (16) into the volume between the trap (14) and the liner (16). Vanes (19) are secured to the exterior surface of the trap (14) and extend into the interior of the tank (14) and the liner (16). Vanes (19) are secured to the exterior surface of the trap (14) and extend into the interior of the tank (10). An elongate edge of each vane (19) is spaced apart from the interior wall of the tank (10) by a capillary distance. As the tank (10) approaches an empty status, liquid propellant collected on the interior wall of the tank (10) spreads to the capillary spacings between the interior wall of the tank (10) and the elongate edges of the vanes (19). The liquid propellant is pumped by capillary action between the vanes (19) and the interior wall of the tank (10) to the exterior surface of the trap (14).
Abstract:
In a liquid storage tank 10 for use on a spacecraft, a transfer apparatus 15 (comprising gathering vanes 33, an elongate array of fins 32, and a sponge structure formed from panels 31) functions to transfer liquid from the inner surface of the tank 10 to the vicinity of an outlet line 40. A screen 23 is disposed between the panels 31 and the outlet line 40. When wetted with liquid, the screen 23 prevents gas and/or vapor in the tank 10 from passing to the outlet line 40. A perforated plate 22 disposed between the screen 23 and the outlet line 40 causes liquid to pass from the tank 10 to the outlet line 40 in a regular and generally unbroken flow.
Abstract:
A system for providing substantially gas-free liquid propellant to the engine(s) of a rocket or space vehicle comprises a storage tank (10) having a first opening (15) that communicates with a "fill, drain and feed" line (17) and a second opening (18) that communicates with a "pressurant and vent" line (20). A hollow trap (13) having a porous inlet window (22) and an exit port (21), which is aligned with the first opening (15), is positioned within the tank (10). A liner (14) having a plurality of porous windows (24) is positioned inside the trap (13), and is secured to the trap (13) circumjacent the inlet window (22) and circumjacent the exit port (21), but is elsewhere spaced apart from the interior wall of the trap (13). The inlet window (22) of the trap (13) and the porous windows (24) of the liner (14) have pores dimensioned to permit passage of liquid propellant therethrough, and to maintain a film of liquid propellant across each pore by surface tension when liquid propellant is not passing therethrough. The films of liquid propellant in the pores of the windows (22) and (24) act as a barrier to the passage of gas therethrough.