Patent ID: 7769549

Claim:
A method for on-line foam quality acoustic monitoring comprising the steps of: placing at least one emitter/receiver pair in close vicinity to a foam flow, emitting at least one acoustic pulse, recording travel time within which the acoustic pulse travels from the emitter to the receiver, determining acoustic pulse speed or sound speed by analyzing an acoustic response of the receiver, measuring pressure in the foam in the area between the emitter and receiver, and calculating foam quality Γ using an equation: Γ = 1 2 ± 1 4 - N ρ fl ⁢ p C fm 2 , where C fm —speed of sound in the foam, p—pressure, ρ fl —fluid density, Γ—foam quality, N—polytrophic expansion coefficient, wherein the reference value, N=1 for isothermal process; and N=1.4 for adiabatic process.