title: [Optimization analysis of ventilation and dehumidification in manned spacecraft].
abstract: OBJECTIVE
  To achieve the optimized design of system operational parameters and system components in air ventilation and dehumidification of manned spacecraft.
  
  
  METHODS
  Mathematical-physical model of air ventilation and dehumidification system was established. Through the design of optimal operational parameters for system performance, heat and moisture in the cabin of manned spacecraft could be removed effectively, dewing could be prevented, and the comfort demand of the astronauts could be met. Equivalent mass of the system in different operational parameters and system components was analyzed by calculation.
  
  
  RESULTS
  The dew point temperature and the comfortability depended on the temperature and humidity of the influx, ventilation rate, and evaporation of moisture in the cabin. There were two ways to control the operational parameters of air ventilation and dehumidification system. The method based on controlling temperature didn't use recuperative heat exchangers in the loop, and the system structure for the design was simple, but it didn't meet the requirement of dissipating moisture in some conditions. The other method was based on controlling the moisture, and it could steadily keep the dew point temperature in the cabin and control the occurrence of dew. But the system structure of this design was relatively complex.
  
  
  CONCLUSIONS
  Mass and power consumption of the system could be reduced by selecting appropriate parameters and adopting the measures of optimization.
authors.affiliation: Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China.
authors.forename: X
authors.initials: X
authors.lastname: Ji
authors.forename: X G
authors.initials: XG
authors.lastname: Liang
authors.forename: J X
authors.initials: JX
authors.lastname: Ren
authors.forename: X R
authors.initials: XR
authors.lastname: Zhang
authors.forename: X H
authors.initials: XH
authors.lastname: Xu
mesh_terms: D000389:Air Conditioning / Q000295:instrumentation / Q000379:methods*; D004780:Environment, Controlled; D004867:Equipment Design; D006801:Humans; D006813:Humidity; D008021:Life Support Systems / Q000295:instrumentation*; D008962:Models, Theoretical; D013026:Space Flight / Q000295:instrumentation*; D018531:Spacecraft / Q000295:instrumentation; D013696:Temperature; D014691:Ventilation / Q000295:instrumentation / Q000379:methods*