Fiber Optic Flow Sensor Research Articles

Cantilever Supported Fiber Bragg Grating Flow Sensor for Space Applications

In this article we report design, mathematical formulation, simulation and fabrication of fiber optic flow sensor using fiber Bragg gratings (FBG) mounted on a cantilever-based transducer support. Design, fabrication and material parameters are optimized in a way that the sensor is operational even at higher flow velocities and finds potentially capable of determining flow rate in rocket fuel tanks for space applications. The reported cantilever supported FBG flow sensor based on simulation results has shown sensitivity to flow rates ranging from 0.1 m/s to as high as 10 m/s flow velocities with varied fuels ranging from liquid hydrogen with density 70.99 kg/m3 to Dinitrogen tetroxide with density 1110 kg/m3. Effect of flow rate is simulated and experimented by placing different weights on the disc and the wavelength shift corresponding to the weights from the designed sensor are recorded. It is observed that the experimental results matched with simulation results to around 50-60%. Flow sensor fabricated is thermally, electrically stable and with its minimal weight finds its extensive use in space applications.

Simulation of a Fiber Optic Flow Sensor for Measuring the Rate and Parameters of Fluid Flows in Astronaut Life Support Systems

The design of a simplified sensing element for the fiber optic sensor used for measuring the rate and parameters of fluid flows is presented together with the diagram of forces acting in the sensing element node. A control flow diagram of the algorithm for fiber optic sensor calculation is suggested. A technique for simulation and calculation of the design and process parameters of the fiber optic sensor is developed.

Self-compensating fiber optic flow sensor system and its field applications.

A self-compensating fiber optic flow sensor system based on the principle of broadband white-light interferometers and cantilever beam bending is described. The fiber optic sensor system uses two fiber ferrule sensors that are bonded on either side of a cantilever beam to measure the flow rate by monitoring the air-gap changes caused by the bending of the cantilever beam. Cross sensitivity of the temperature and pressure dependence of the sensor can be compensated for automatically. The prototype sensor system was constructed, laboratory characterized, and field tested. The results from the field testing have demonstrated high resolution, repeatability, and stability for on-line detection of the flow rates of fluids.