Today, the only solutions on the market for measuring 2D velocity fields are laser-based optical methods (such as particle imaging velocimetry: PIV).
These are limited by the need for optical access to the flow and are therefore inapplicable on opaque fluids (such as liquid metals) or through opaque pipes (such as metal pipes, the majority in industry).
To overcome this limitation and meet new challenges (in research and industry) it is possible to rely on acoustic imaging methods.

The LISM (CEA Cadarache Instrumentation Laboratory) has been working for several years on the development of an industrial acoustic PIV (or echo-PIV) method.
An initial thesis has led to significant progress, and the CEA is now planning to market echo-PIV scanners through a start-up project.
However, there are still a number of hurdles to overcome, in particular that of imaging through walls with high acoustic impedance differences.

Your main objective will be to remove these obstacles. This mission will be structured as follows:
- Bibliographical study and familiarisation with the echo-PIV method
- Numerical study and development of a solution to resolve the problems of energy transmission through the metal wall
- Experimental validation of the detection of microscopic reflectors through a metal wall
- Numerical study and development of a solution to the problem of multiple reflection within the metal wall, leading to poor reconstruction of the final image
- Experimental validation of the solution to the reflection problem
- Adaptation of the acoustic imaging method to simultaneously resolve the transmission and reflection problems
- Publication in scientific journals (and/or patents)