Patent attributes
A process for determining a fluid flow velocity and then a mass flow rate of a cryogenic fluid in which a Helmholtz resonator is used to detect a presence of a two-phase flow in a conduit. The process first measures a frequency of the fluid flow, then determines a speed of sound of the fluid from the frequency, then measures the temperature of the fluid flow, and from the speed of sound and the temperature determines a quality of the fluid flow (liquid or vapor), and from the frequency and the fluid quality determines a Strouhal Number. The fluid flow velocity is found from an equation relating the frequency and a diameter of the surface area to the Strouhal Number. The mass flow rate is found from the fluid flow velocity and the temperature.