Characteristics and Performance of the Japanese Experimental Module (JEM) Air Ventilation

The Japanese Experimental Module (JEM) Pressurized Module (PM) is a facility where astronauts conduct experiments or control the total JEM facility. Inside the PM, the air composition, temperature and humidity are controlled so as to be comfortable for astronauts' activity all the time. The verification of the on-orbit performance of the functions constituting a manned space system is one of the critical points. Computational Fluid Dynamics (CFD) simulation technology is utilized to characterize and investigate the airflow in the JEM for various operating conditions. The development of a successful CFD model for International Space Station (ISS) operation is useful because there are always off-nominal and other contingency operations, which might occur and could be analyzed using an existing CFD model. This paper also presents the cabin ventilation test data obtained from the JEM flight module. The CFD model analysis results are correlated to the module ventilation test data to be most useful in predicting the performance of future systems. The JEM ventilation performance for the cabin aisle way is addressed along with performance comparisons with the U.S. Laboratory module and the Service Module cabin air ventilation.