International Space Station USOS Crew Quarters Development

Preliminary Numerical Studies for the Improvement of the Ventilation System of the Crew Quarters on Board of the International Space Station

“…Case 1 was already presented in detail in [7]. This configuration of the air diffuser is composed by four rectangular regions, each of them having independent vertical and horizontal guiding vanes [3,5,6]. For the Case 1 the unstructured tetrahedral mesh has 4.8 million elements, for Case 2 the mesh has 5.7 million cells.…”

“…For the boundary conditions, we imposed three mass flow rates corresponding to the three positions of the fan controller: low, medium and high, 108 m 3 /h, 138 m 3 /h and 196 m 3 /h [3], respectively. The inlet air temperature was in all cases 18°C corresponding to the air taken from Node 2.…”

“…The ventilation system's main objective is to flush the carbon dioxide concentration, which in high levels represents an asphyxiation hazard. Inside the CQ, the air receives the crew member's metabolic heat (considered to be between 100 and 132 W) and the electronics heat (around 153 W) [3,5,6]. The air is then directed though the CQ exhaust duct outlet and directed parallel to the rack face and down the aisle way toward the Node 2 CCAA air return.…”

“…The total deployed volume of a CQ is around 2.1 m 3 and it was desirable to provide as large a habitable volume for the crew member as possible with the respect of the configuration to a standard US rack volume [3,5,6]. The structure of a CQ is divided into three main areas: bump-out, rack, and pop-up ( Figure 2).…”

“…Last but not least, all of the systems need to be as energetically efficient as possible, while having a long lifespan and offering easy access to manual intervention as well as redundancy protection. The current CQ solution was designed to fit inside the standard rack spaces present on the ISS, [3,4]. The ventilation system is composed of two axial fans, one used for the introduction of air into the CQ, the other for its extraction.…”