The Application of MFR in Ventilation System Design

To meet crew comfort criteria, remove CO₂, control contaminant and so on, the velocities of cabin air are required to be distributed within a specified range. A Computational Fluid Dynamic (CFD) model of a given space station cabin is built to study the velocity distribution of cabin air, especially when the air flowrate varies. This paper introduces a new conception: the Margin of FlowRate (MFR). The characteristic of the MFR and its application are introduced. The MFR specifies a flowrate range based on the velocity distribution requirements. When air flowrate varies within this range, the velocity distribution of cabin air can always meet the requirement. As the safety is emphasized increasingly, the MFR will be proved useful in designing and qualifying the ventilation system.