METHOD FOR SUSTAINING OF AIR COMPOSITION IN CLOSED WORKING VOLUME Russian patent published in 2002 - IPC

FIELD: sustaining of constant composition of air in a closed working volume, in which the gas composition is changed as a result of physicochemical processes without any ingress in it of aerosols, bacteria and other particles from the ambient. SUBSTANCE: method consists in a gas exchange with the environment by means of a membrane, the air is forced to flow along the inner and outer surfaces of a track membrane with a diameter of pores equal to ≥0,20 μm without any differential of the normal component of pressure of the membrane in the condition, when Nusselt number Nu determining the resistance of the track membrane to mass transfer through its incoming air layers equals: Nu = 0,0180 Re^0,8, provided Re = Vde/ν>10⁴, where: V-air speed along the membrane; V-kinematic viscosity; de - equivalent diameter of the duct for gas flow. EFFECT: enhanced intensity of mass transfer of air gas components per unit of the membrane area for sustaining of processes of life support in a closed working volume, as well as protection of the closed volume against ingress of aerosols from the ventilated (external) volume. 3 dwg