SPACECRAFT THERMAL AND FLUID MANAGEMENT SYSTEMS
To manage propellant in a spacecraft, the method of this disclosure includes storing propellant in a tank as a mixture of liquid and gas; transferring the propellant out of the tank; converting the mixture of liquid and gas propellant into a single phase, where the single phase is either liquid or gaseous; and supplying the single phase of the propellant to a thruster.
1 . A method for managing propellant in a spacecraft, the method comprising:
storing propellant in a tank as a mixture of liquid and gas;
transferring the propellant out of the tank;
converting the mixture of liquid and gas propellant into a single phase, where the single phase is either liquid or gaseous; and
supplying the single phase of the propellant to a thruster.
2 . The method of claim 1 , wherein
converting the propellant into a single phase includes converting the mixture of liquid and gas propellant directly into liquid.
3 . The method of claim 2 , wherein
converting the mixture of liquid and gas propellant directly into liquid includes compressing the propellant using a piston.
4 . The method of claim 1 , wherein
converting the mixture of liquid and gas propellant into the single phase includes converting the propellant directly into gas.
5 . The method of claim 1 , wherein
converting the mixture of liquid and gas propellant into a single phase includes:
first converting the mixture of liquid and gas propellant into gas, then converting the gas into liquid.
6 . The method of claim 1 , wherein converting the mixture of liquid and gas propellant into the single phase includes drawing the liquid through a wicking material into a liquid-phase pump.
7 . The method of claim 6 , further comprising:
causing a low-density vapor-phase of the propellant to condense onto a cooled complex surface at a temperature below a dew point of the propellant but above the freezing point of the propellant.
8 . The method of claim 6 , wherein the complex surface is composed of loosely packed hydrophilic fibers.
9 . The method of claim 6 , further comprising:
progressively compressing, using a peristaltic-type pump, the wicking material along a wave which forces liquid out of the wicking material and toward an output port.
10 . The method of claim 1 , wherein converting the mixture of liquid and gas propellant into the single phase includes:
evaporating the mixture to a complete vapor phase; and
condensing the complete vapor phase to a complete liquid phase.
11 . The method of claim 10 , wherein the evaporating includes:
directing a stream of the mixture through a restrictive orifice to generate an abrupt pressure drop to flash-evaporate the mixture.
12 . The method of claim 11 , wherein the condensing includes:
adding heat to the mixture using a warmed evaporator to generate a low-pressure vapor;
compressing a stream of the low-pressure vapor to generate a pressurized vapor with a higher pressure using a vapor pump; and
condensing the pressurized vapor to the complete liquid phase using a cooled condenser.
13 . The method of claim 12 , further comprising:
transferring heat from the cooled condenser to the warmed evaporator.
14 . The method of claim 10 , wherein evaporating the mixture to the complete vapor phase includes passing the mixture in pulses through a fast-acting valve into a low-pressure chamber.
15 . A spacecraft comprising:
a tank storing propellant in a tank as a mixture of liquid and gas;
a thruster configured to consume the propellant to generate thrust;
a two-phase intake component configured to configured to receive the mixture of liquid and gas from the tank; and
a phase conversion component configured to (i) receive the mixture of liquid and gas from the two-phase intake component, (ii) convert the mixture of liquid and gas into a single phase of the propellant, and (iii) supply the single phase of the propellant to the thruster.
16 . The spacecraft of claim 15 , wherein:
the two-phase intake component includes porous wicking material to absorb the mixture; and
the phase conversion component includes a mechanism configured to compress the porous wicking material to thereby extract a liquid phase of the propellant.
17 . The method of claim 16 , wherein:
the phase conversion component further includes a cooled complex surface, and
the phase conversion component causes a low-density vapor-phase of the propellant to condense onto the cooled complex surface at a temperature below a dew point of the propellant but above the freezing point of the propellant.
18 . The spacecraft of claim 17 , wherein the complex surface is composed of loosely packed hydrophilic fibers.
19 . The spacecraft of claim 15 , wherein:
the phase conversion component includes a piston configured to convert the mixture of liquid and gas propellant directly into liquid.
20 . The spacecraft of claim 15 , wherein the phase conversion component is configured to:
evaporate the mixture to a complete vapor phase; and
condense the complete vapor phase to a complete liquid phase.