HIGH-TEMPERATURE, HIGH PRESSURE ACOUSTIC RESONANCE CELL

摘要

A compact, rugged and portable measurement cell design for the determination of sound speed in fluids at temperatures up to 250° C. and pressures up to 3,000 psi is described. Swept Frequency Acoustic Interferometry measurement for liquid sound speed determinations in liquids up to 250° C. is of both fundamental interest, as in the case of basic equations of state, and applied interest, such as for characterizing geothermal or petroleum down hole environments. Representative sound speeds for water, as a function of temperature and pressure, are in agreement with an internationally accepted standard for the sound speed of water.

主权项

1. A high-temperature, high-pressure acoustic resonance cell, comprising:
a first piezoelectric transducer; a first enclosure effective for protecting said first transducer from mechanically and chemically harsh environments, said first enclosure having a first side with a flat exterior surface and a flat interior surface parallel thereto, and wherein said first transducer is acoustically coupled to the interior surface of the first side; a second piezoelectric transducer; a second enclosure effective for protecting said second transducer from mechanically and chemically harsh environments, said second enclosure having a second side with a flat exterior surface and a flat interior surface parallel thereto, wherein said second transducer is acoustically coupled to the interior surface of the second side, and wherein the exterior surface of the first side of said first enclosure and the exterior surface of the second side of said second enclosure are parallel and spaced apart a selected distance, forming thereby a volume; a spacer member for establishing and maintaining the selected distance and parallel disposition of the first side and the second side; a signal generator for supplying a chosen time-varying electrical signals to said first piezoelectric transducer; a signal gain and phase analyzer for receiving electrical signals from said second transducer; and a processor for processing the received electrical signals from said signal gain and phase analyzer, and for controlling said signal generator.