ANALYSIS OF THE EFFICIENCY OF RECTIFYING PLATES IN CROSS MOTION OF PHASES V. N. Pavlechko UDC 66.048.375 The efficiency of rectifying plates in cross motion of phases is analyzed. The equilibrium of vapor escaping from an ideal plate with a mean content of liquid on the plate equal to the mean value of vapor composition at the inlet and outlet from the plate is assumed. Four versions of interaction between an ideal and an actual plate are suggested. The equality of the efficiencies in vapor and liquid phases in each version is proved. Some versions are compared to the Murphree and Hausen models. The ratios between the efficiencies of the plates are obtained for the considered versions. JEPTER74920199922 JEPTER7492022