Passive low gravity cryogenic storage vessel

A vessel for storing cryogenic fluid in a reduced-gravity environment, wherein the fluid includes a liquid phase which is provided to an external device and a gas phase, said vessel comprising:

• a storage tank for holding the cryogenic fluid under pressure;
• a screen trap defining a plurality of apertures which are sized to prevent the flow of the gas phase therethrough yet allow the flow of the liquid phase therethrough, said screen trap extending across said storage tank for dividing said tank and creating a liquid phase compartment which is substantially filled with the liquid phase of the cryogenic fluid and a gas phase compartment for confining gaseous cryogenic fluid;
• a feed valve having an inlet in said liquid phase compartment through which the liquid phase of the cryogenic fluid is withdrawn from said storage tank and provided to the external device;
• a relief valve for releasing substantially gaseous cryogenic fluid from the interior of said storage tank when said cryogenic fluid exceeds a predetermined maximum pressure;
• at least one conduit having an inlet in said liquid phase compartment and extending to said relief valve so that pressure within said storage tank causes cryogenic fluid to flow from said liquid phase compartment into said conduit, said conduit having a first heat exchanger portion extending within said liquid phase compartment and a second heat exchanger portion extending within said gas phase compartment;
• and
• at least one throttle adjacent said inlet of said conduit and upstream of said first heat exchanger portion for reducing the pressure and temperature of the cryogenic fluid as the fluid flows therethrough such that said first heat exchanger portion passes reduced temperature cryogenic fluid through said liquid phase compartment and heat is transferred from the liquid phase to the cryogenic fluid within said first heat exchanger portion, and such that said second heat exchanger portion passes reduced temperature cryogenic fluid through said gas phase compartment and heat is transferred from the cryogenic fluid in the gas phase compartment to the cryogenic fluid within said second heat exchanger portion.

A vessel for storing cryogenic fluid in a reduced-gravity environment, wherein the fluid includes a liquid phase which is provided to an external device and a gas phase, said vessel comprising:

• a storage tank for holding the cryogenic fluid under pressure;
• a screen trap defining a plurality of apertures which are sized to prevent the flow of the gas phase therethrough yet allow the flow of the liquid phase therethrough, said screen trap extending across said storage tank for dividing said tank and creating a liquid phase compartment which is substantially filled with the liquid phase of the cryogenic fluid and a gas phase compartment for confining gaseous cryogenic fluid;
• a feed valve having an inlet in said liquid phase compartment through which the liquid phase of the cryogenic fluid is withdrawn from said storage tank and provided to the external device;
• a relief valve for releasing substantially gaseous cryogenic fluid from the interior of said storage tank when said cryogenic fluid exceeds a predetermined maximum pressure;
• at least one conduit having an inlet in said liquid phase compartment and extending to said relief valve so that pressure within said storage tank causes cryogenic fluid to flow from the liquid phase compartment into said conduit, said conduit having first, second and intermediate heat exchanger portions, said first heat exchanger portion extending within said liquid phase compartment, said intermediate heat exchanger portion traversing and being in conductive contact with said screen trap, and said second heat exchanger portion extending within said gas phase compartment;
• and
• at least one throttle adjacent said inlet of said conduit and upstream of said first heat exchanger portion for reducing the pressure and temperature of the cryogenic fluid as the fluid flows therethrough such that said first heat exchanger portion passes reduced temperature cryogenic fluid through said liquid phase compartment and heat is transferred from the liquid phase to the cryogenic fluid within said first heat exchanger portion, and such that said intermediate heat exchanger portion passes reduced temperature cryogenic fluid adjacent to said screen trap for conductive heat transfer to said conduit, and such that said second heat exchanger portion passes reduced temperature cryogenic fluid through said gas phase compartment and heat is transferred from the cryogenic fluid in said gas phase compartment to the cryogenic fluid within said second heat exchanger portion.