in the present  paper electrical conductivity (ec) of colloidal gas aphron (cga) suspensions was measured for anionic and cationic surfactants (sodium dodecyl sulfate (sds) and tetradecyl trimethyl ammonium bromide (ttab)). experiments were made for different concentrations of sds (6, 8.1, 10 mm) and ttab (2, 3.51, 5 mm). cga drainage behavior was observed and measured using 1 liter measuring c...

The evolution of a foam is determined by drainage flow of the continuous (liquid) phase and coarsening (aging) of the dispersed phase (gas bubbles). Free-drainage experiments with slow- and fast-coarsening gases show markedly different dynamics and elucidate the importance of the coupling of the two effects. Strong coarsening leads to drainage times that are shorter (accelerated drainage) and i...

We have studied bubble motion within a column of foam allowed to undergo free drainage. We have measured bubble motion upward with time and as a function of their initial positions. Depending on the gas used, which sets the coarsening and drainage rates, different bubble upward motion types have been identified (constant speed, acceleration or deceleration) and explained in relation with liquid...

Gravity drainage is the main mechanism which controls the oil recovery from fractured reservoirs in both gas-cap drive and gas injection processes. The liquid bridge formed between two adjacent matrix blocks is responsible for capillary continuity phenomenon. The accurate determination of gas-liquid interface profile of liquid bridge is crucial to predict fracture capillary pressure precisely. ...

– Experiments on foam drainage have so far only been performed in essentially one-dimensional flow geometries aligned with the direction of gravity. Here a foam-filled HeleShaw cell is used to examine pulsed drainage, which is the flow of a finite liquid volume, both along and perpendicular to the direction of gravity. An exact similarity solution to the generalized foam drainage equation exist...

Foam drainage varies with surfactant. We present direct measurements of the flow velocity profiles across single Plateau borders, which make up the interconnected channel-like network for liquid flow. For protein foams the interface is rigid, whereas small-surfactant foams show significant interfacial mobility. The results agree with a model that takes into account the shearing of the liquid-ga...

We investigate the drainage of a 2D microfoam in a vertical Hele-Shaw cell, and show that the Marangoni stress at the air-water interface generated by a constant temperature gradient applied in situ can be tuned to control the drainage. The temperature gradient is applied in such a way that thermocapillarity and gravity have an antagonistic effect. We characterize the drainage over time by meas...

Liquid-infused surfaces display advantageous properties that are normally associated with conventional gas-cushioned superhydrophobic surfaces. However, the surfaces can lose their novel properties if the infused liquid drains from the surface. We explore how drainage due to gravity or due to an external flow can be prevented through the use of chemical patterning. A small area of the overall s...

The drainage of liquid through a foam involves flow in channels, also called Plateau borders, which generally are long and slender. We model this flow by assuming the flow is unidirectional, the shear is transverse to the flow direction, and the liquid/gas interfaces are mobile and characterized by a Newtonian surface viscosity, which does not depend on the shear rate. Numerical finite differen...

A method has been developed to infer the wettability of steam-water-rock systems based on the relationship between permeability and capillary pressure by Purcell. The Purcell model was extended to two-phase flow to verify whether the wettability is a function of water saturation. The results calculated using the experimental data showed that the wettability index in drainage was greater than th...