Densifier for simultaneous conditioning of two cryogenic liquids

A densified propellant management system comprising a densifier, and a cryogenic temperature probe, wherein said densifier comprises an oscillatory power source for generating oscillatory power and a pulse tube refrigerator, said pulse tube refrigerator being a two-stage pulse tube refrigerator having a first stage refrigeration unit and a second stage refrigeration unit, said first stage refrigeration unit being adapted to supercool a first cryogenic liquid to a first cryogenic temperature, said second stage refrigeration unit being adapted to supercool a second cryogenic liquid to a second cryogenic temperature, wherein said second cryogenic temperature is lower than said first cryogenic temperature.

A densifier comprising an oscillatory power source for generating oscillatory power and a pulse tube refrigerator, said pulse tube refrigerator comprising a first stage refrigeration unit that is adapted to supercool a first cryogenic liquid to a first cryogenic temperature.

A method comprising:

• a) providing a densifier comprising an oscillatory power source for generating oscillatory power and a pulse tube refrigerator, said pulse tube refrigerator being a two-stage pulse tube refrigerator having a first stage refrigeration unit and a second stage refrigeration unit, said first stage refrigeration unit being adapted to supercool a first cryogenic liquid to a first cryogenic temperature, said second stage refrigeration unit being adapted to supercool a second cryogenic liquid to a second cryogenic temperature, wherein said second cryogenic temperature is lower than said first cryogenic temperature;
• and
• b) operating said densifier thus simultaneously supercooling said first cryogenic liquid to said first cryogenic temperature in said first stage refrigeration unit and said second cryogenic liquid to said second cryogenic temperature in said second stage refrigeration unit.