Fluid delivery systems

摘要

A system for measuring flow of fluid delivered through a line, the system comprising:
an acoustic energy source for acoustically exciting gas in an acoustically contiguous region at only a single frequency, to produce an acoustic response associated with a change of a volume of a subregion of the acoustically contiguous region caused by fluid in a zone coupled to the volume of the subregion;
a first acoustic transducer, mounted at a first position in the acoustically contiguous region, for producing an electrical signal based on the acoustic response, the electrical signal of the first acoustic transducer having a phase relationship with respect to a reference; and
a processor, coupled to the first acoustic transducer and to the reference, for determining a quantity related to change of volume of the subregion based on temporal evolution of the phase relationship.