ON THE SEAL EFFECT OF THE LABYRINTH PACKING IN A VERY SMALL CLEARANCE.

Abstract

IN THIS PAPER, THE SEAL EFFECT OF THE STRAIGHT-THROUGH LABYRINTH PACKING WITH AN INLET LENGTH OF THE STATIONARY TYPE WAS EXPERIMENTALLY STUDIED,WHEN THE CLEARANCE WAS ABOUT 0.06 MILLIMETRE.THE RESULTS OBTAINED ARE AS FOLLOWS.(1) THE SEAL EFFECT DEPENDS ON THE CLEARANCE EPSILON, PRESSURE RATIO, DEPTH H AND WIDTH B OF THE GROOVE AS WELL AS ON THE TOTAL LENGTH OF THE LABYRINTH PACKING AND THE INLET LENGTH.(2) THE RATIOS OF H/B AND EPSILON/B, WHICH GIVE THE MAXIMUM SEAL EFFECT, WERE 0.15 # 0.20 AND ABOUT 0.10, RESPECTIVELY, WHILE THE CORRESPONDING REPORTED VALUES OF AN OVER 0.2 MILLIMETRE CLEARANCE WERE 0.20 # 0.30 AND ABOUT 0.15, RESPECTIVELY.(3) BY USING THE ABOVE RESULTS, AN EMPIRICAL FORMULAR INCLUDING ALL THE FACTORS WAS DETERMINED FOR THE EFFECT ON AIR LEAKAGE.ACCORDING TO THIS, THE OPTIMUM FORM OF THE LABYRINTH PACKING, WHICH GIVES THE MAXIMUM SEAL EFFECT, CAN BE FOUND FOR A VERY SMALL CLEARANCE.