Novel, Spatially-distributed Optical Sensor for Unsteady Surface Pressure Field Mapping

PSI proposes to demonstrate the feasibility of developing an optically-based sensor for real-time measurement of unsteady water turbulence pressure fields with high sensitivity and a large dynamic range. The sensor is based on a fiber Bragg grating (FBG) sensing technique applicable for high-speed measurements, incorporating multiple transducers to enable spatially resolved pressure detection. The innovative detection technology relies on time-domain spectral measurements that enable high spectral resolution and time multiplexing of multiple sensing points. The design uses a unique mechanical transducer that coverts pressure to strain with a large magnification ratio for and detection sensitivity and high dynamic range. During Phase I, PSI will develop theoretical models to simulate water turbulence conditions and measurement characteristics of the envisioned FBG pressure sensor. A prototype with one sensing element will be developed and tested to demonstrate feasibility. The successful feasibility experiment will lay the foundation for the Phase I Option development and testing of an expanded sensor system, including 10 spatially-distributed sensing elements. Successful completion of the Option program will support the development and testing of a complete turbulence pressure sensor with 100 sensing elements during Phase II. The effort leverages PSI experience developing and commercializing innovative spectroscopy sensing technologies and systems.