CREEP FLOW AND PRESSURE RELAXATION IN BUBBLY MEDIUM

General equations governing the slow creep motion of a nonlinear visco us, incompressible medium containing a large number of small gas bubbl es are analyzed on the basis of asymptotic averaging methods for perio dic structures. Special attention is paid to account for the interacti on of bubble compression (decompression) relaxation and deviatoric mac ro deformations in the two-phase system. The corresponding approximate rheological relations and averaged macroscale mass and momentum balan ce equations are derived. The relationship between gas-medium pressure drop and volume expansion (compression) rate, as well as the one betw een deviatoric macro-stresses and macro-strain rates are numerically e xamined in application to bubbly ice rheology. Copyright (C) 1996 Else vier Science Ltd.