Figure: (a) ~ (c) Viscous fingering pattern for the gel elasticity is (a) low (b) medium (c) high. (d) Results obtained from stability analysis of flow interface considering viscoelastic properties. In the x-axis, β−1 < 0 or β−1 > 0 means that the gel has shear thinning viscosity or shear thickening viscosity. In the y-axis, η2 > 0 is the shear viscosity of the gel at a certain shear rate.