Abstract

This paper reports an ultrasonic waveguide sensor for liquid level measurements using three guided wave modes Longitudinal L(0,1), Torsional T(0,1) and Flexural(1,1) simultaneously. These wave modes were simultaneously transmitted/received in a thin stainless-steel wire-like waveguide using a standard shear wave transducer. Experiments were conducted in non-viscous fluid (water) and viscous fluid (castor oil). It was observed that the flexural F(1,1) wave mode showed a change in both time of flight (due to change in velocity and dispersion effects) and amplitude (due to leakage) for different levels (0-9cm) of immersion of the waveguide in a fluid media. For the same level of immersion, the L(0,1) and the T(0,1) modes show only relatively smaller change in amplitude and no change in time of flight were observed. The experimental results were validated using Finite Element Model (FEM) studies. Also, by monitoring all three wave modes simultaneously, a more versatile and redundancy in measurements of the fluid level inside critical enclosures of processing industries can be achieved by compensating for changes in the fluid temperature using one mode while the level is measured using another. This ultrasonic waveguide technique will be helpful for remote measurements in physically inaccessible areas and in hostile environments.

How to Cite:

Raja, N. . & Balsubramaniam, K. ., (2019) “Ultrasonic waveguide based level measurement using fundamental guided wave mode L(0,1) T(0,1) and F(1,1) simultaneously”, Review of Progress in Quantitative Nondestructive Evaluation .