USSRC Proprietary 2015

ECLSS PANELS Orbiter ML31C L1 & L2 MEDS – Multi-function electronic Display System retrofitted to Atlantis 1999

Space Station Regenerative ECLSS Flow Diagram (Current)

ECLSS: Air Earth I.Pressurization System - supplies breathable air 1. ~79% Nitrogen 2. ~21% Oxygen 3. < 1% Trace Elements psi A. Earth’s Atmosphere

I. Pressurization System (cont) B. Orbiter Components 1.80% Nitrogen (11.2 psi*) 2.20% Oxygen (3.5 psi*) 3.*partial pressures do not correspond to percentages 4. Pressure varies: nominal cabin leak check before EVA ECLSS: Air Orbiter Only N2 & O2 stored midfuselage

I.Pressurization System (cont.) D. Station Components 1.80% N2, 20% O2 2.Pressure 14.7 psi E. Station Supply – N2 & O2 tanks: Progress – O2 source: electrolysis – Backup O2: solid cartridges (exothermic) Oxygen Hydrogen Electrolysis Graphic: News-StationAir.asp ECLSS Air Station Only

II. Air Revitalization System (ARS) – cleans used air A. ARS Microfilters-traps dust, hair, skin cells, etc… B. LiOH canisters-removes carbon dioxide C. ATCO (Ambient Temperature Catalytic Oxidizer) - turns CO into CO 2 LiOHCanisters ECLSS: Air Orbiter Only

II.Air Revitalization System (ARS) – cleans used air A. Gas Analyzers: check levels of O2, toxic gases; O2 added automatically as needed B. CDRA – Carbon Dioxide Removal Assembly - rechargeable CO2 removers ECLSS Air Station Only

II.Air Revitalization System (ARS) – cleans used air C. Trace Contaminant Control Subassembly – filters gas contaminants with charcoal D. Harmful Impurities Filter – backs up TCCS ECLSS Air Station Only

ECLSS: Air Orbiter/Station II. Air Revitalization System (cont) D. Heat Exchanger -Nominal temperature:65-80°F -Nominal humidity: 35-60% -Cabin air passes or bypasses heat exchanger -Station temp, humidity more consistent & homogeneous than orbiter

III. Supply and Waste Water – Panel ML31C A. Fuel Cells -produce water as a by- product of electricity -purge for peak performance B. 5 tanks: 75 gallons total A – drinking water B,C,D – cooling system E – waste water ECLSS: Water Orbiter Only

How Do You Go To The Bathroom In Space?

ECLSS: Water Station Only III. Supply and Waste Water A. Finite supply brought via Progress or Shuttle B. May 2009: total recycling via Boeing’s Water Recovery and Management Subsystem

IV.Active Thermal Control System (ATCS) a) Water Coolant Loops b) Freon Coolant Loops c) Water Freon Exchanger d) Flash Evaporators -topping evaporators -high load evaporators -ammonia evaporators Heat exchanger To Freon Exchanger & loops ECLSS: Temp Orbiter Only

IV.Common Cabin Air Assembly (Station) A.Similar to coolant loops & ATCS on orbiter B.Water coolant in racks, ammonia to radiators C.Ventilator locations: 1.Individual racks 2.Within modules 3. Between modules ECLSS : Temp Station Only Click Picture Click Picture

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ECLSS Review ECLSS regulates 3 things: Air - pressure & revitalization Temperature Water – supply & waste Nominal air components: N2 – 80% (11.2 psi) O2 – 20 % (3.5 psi) Nominal Temp & Humidity: F, 35-60%

ECLSS Review Nominal Pressures: 14.7 psi, on orbit (orbiter & ISS) 16.7 psi (orbiter) cabin leak check 10.2 psi (orbiter) pre-EVA Air cleaning methods (orbiter) ARS microfilters LiOH canisters

ECLSS Review What process cleans fuel cells? Purge 2 orbiter coolants: water and freon 2 Station coolants: water and ammonia

ECLSS Review Use flash evaporators when: PBD closed Which evaporators will move you? High load Use ammonia flash evaps when: Below 100,000 feet Good Luck on your ECLSS Activity !