ACOUSTIC-IMPEDANCE METHOD TO MEASURE LEVELS OF LIQUID MEDIA Russian patent published in 2004 - IPC

FIELD: automatics, measurement technology. SUBSTANCE: proposed method can be utilized in heat power industry, in chemical, oil and other industries to measure levels of liquid media in tanks. Method includes placement of metal waveguide in liquid medium along height of tank, excitation of longitudinal elastic wave of zero order in one end of metal waveguide, reading of forward wave and wave reflected from the other end of waveguide of elastic waves of zero order, determination of intensity levels of forward and reflected elastic waves of zero order. Voltages of forward and reflected signals corresponding to intensities of forward and reflected elastic waves of zero order are memorized in sequence by first and second storage locations with capacitors C. Resistor is connected to first storage location with capacitor C. Voltages of forward and reflected signals are compared. Time interval from moment of connection of resistor to first storage location with capacitor C to moment of equality of voltage across resistor R and voltage across capacitor C of second storage location is measured. EFFECT: secured constancy of sensitivity of acoustic-impedance method measuring levels of liquid media in range of conversion. 1 cl, 2 dwg