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Basic Flow Description

The chamber is an open, continuous flow system, in which CO2 flows from a high pressure bottle down to a vacuum pump. Specifically, CO2 from a bottle (station A) is passed through a humidity generator (stations B, C, D, & E) to a critical orifice (station F), which expands the flow to Mars ambient pressure. This expansion both reduces humidity and pressure. This conditioned flow enters a test chamber (station H) which is located inside a freezer (station G) that maintains the desired Mars ambient temperature. After exiting the test chamber the gas passes through a chilled mirror hygrometer (station I), which measures the frost point. Finally, the flow passes through a cold trap (station J) and into one or two vacuum pumps (station K).

Basic Flow Schematic

Basic Flow SchematicStation identification

  1. CO2 bottle
  2. Mass Flow Controller (MFC) #1
  3. MFC #2
  4. CO2 Dryer
  5. CO2 Saturator
  6. Critical Orifice
  7. Low Temperature Freezer
  8. Test Chamber
  9. Chilled Mirror Hygrometer
  10. Cold Trap
  11. Vacuum pump (2 pumps in parallel)

Test Chamber

Test Chamber Schematic