Surfactant spreading on thin liquid films on chemically patterned surfaces

The injection of surfactant solutions is a promising technique for enhanced oil recovery from sub-surface reservoirs. Towards a quantitative understanding of the fluid-mechanical aspects of the process, we conducted a combined experimental and numerical study of the spreading dynamics of soluble and insoluble surfactants on confined thin liquid films. To good approximation the surfactant front propagates according to a power-law relation [formula]. We determined the spreading exponents alfa for different film thicknesses and initial conditions and found a favorable agreement between experiments and simulations