Volume 31, Issue 1 (January 2003)
The Wave-in-a-Tube Method for Estimation of Mechanical Properties of Viscoelastic Materials Using Ultrasound
The wave-in-a-tube method allows for the estimation of material properties of gel-like, viscoelastic materials utilizing only a pair of matched ultrasonic pressure transducers. To employ this technique, a sample tube must be manufactured that (1) has an inside diameter that fits snugly around the element of the transducers being utilized, (2) is as long as the specimen size will allow given the diameter required, and (3) is made of a low-density, solid material. After construction of the container, the sample to be measured is placed in the tube with a pressure transducer fitted into each end with large air pockets eliminated. An ultrasonic pulse is sent through the sample, and the resulting waveform is analyzed per the Reynolds wave-in-a-bar method, yielding the magnitude of the complex moduli.