Patent ID: 8114221

Claim:
A method for cleaning an internal surface of a narrow diameter channel, method comprising the steps of: i) flowing a liquid cleaning medium and a gas at a pressure of 35 psi or less through the narrow diameter channel under a flow regime that creates surface flow entities in contact with and sliding along the internal surface of the narrow diameter channel, said surface flow entities having three-phase contact lines and associated menisci, said surface flow entities detaching contaminants with which they come in contact from the internal surface of the narrow diameter channel, wherein the narrow diameter channel has a diameter of about 0.02 centimeter to about 1.6 centimeters, and a length of about 0.75 meter to about 5 meters, wherein the internal surface of the narrow diameter channel is a hydrophobic surface, and wherein the surface flow entities exhibit an advancing contact angle greater than 50 degrees and a receding contact angle greater than zero degree; ii) rinsing the internal surface of the narrow diameter channel to remove residual liquid cleaning medium and detached contaminants from the internal surface of the narrow diameter channel; wherein during step i): the detachment of contaminants from the internal surface of the narrow diameter channel is produced by a sweeping of the internal surface of the narrow diameter channel with the three-phase contact lines of the surface flow entities, the cleaning medium is not predispersed in the gas as droplets before entering the channel, and less than 10% of the internal surface of the narrow diameter channel is covered by a contiguous annular film.