The determination of the viscoelastic properties of liquid materials at ultrasonic frequencies by CW mode impedance measurements

A method is described for measuring shear mechanical properties of liquids at ultrasonic frequencies. The method is based on the process of the electrical impedance of a sensor in contact with the liquid. The sensor is composed of a piezoelectric transducer bonded to a delay line. The process determines the complex reflection coefficient of shear waves reflecting from the delay line-liquid interface, and the mechanical impedance is deduced. Experimental determination of dynamic shear properties of a series of saccharose solutions is presented as an example of the method.