Sensing physical fluid properties with CMUT arrays

Fluid waves at the interface of CMUTs (Capacitive Micromachined Ultrasound Transducers) to the surrounding fluid are an often discussed and unwanted effect for medical imaging applications, as they cause ringing artifacts. A new approach for a surface wave sensor is presented which uses these dispersive surface waves for sensing fluid properties like mass density and viscosity. After a short introduction to the theory and our FEM model we will present first results. A mixture of water and glycerin was used to investigate the sensitivity of the sensor to dynamic viscosity.