EFFECT OF GEOMETRY AND ANISOTROPY OF A HELE-SHAW CELL ON VISCOUS FINGERING OF POLYMER-SOLUTIONS

Viscous fingering patterns of hydroxypropyl methyl cellulose (HPMC) so lutions were investigated by forcing air in radial and linear geometry Hele-Shaw cells with radial and linear geometry as functions of HPMC concentration and applied pressure. The resulting patterns depended on the HPMC concentration and the cell geometry and anisotropy. The char acteristic quantities of pattern growth, such as the finger tip veloci ty and the finger width, were evaluated. The tip velocity in the aniso tropic linear cell was almost the same as that in the radial one, more over, the finger width was well correlated with the pattern morphologi cal changes.