Development of an optical fiber flow velocity sensor.
A new optical fiber flow velocity sensor was developed by using an optical fiber information network system in sewer drainage pipes. The optical fiber flow velocity sensor operates without electric power, and the signals from the sensor can be transmitted over a long distance through the telecommunication system in the optical fiber network. Field tests were conducted to check the performance of the sensor in conduits in the pumping station and sewage pond managed by the Tokyo Metropolitan Government. Test results confirmed that the velocity sensor can be used for more than six months without any trouble even in sewer drainage pipes.
A Circular Target Flow Measurement System
Based on the relation between the wavelength shift of sensing FBG and the strain, a flow measuring device of the circular target binding Fiber Bragg Grating with the cantilever is designed and the mathematical model based on a circular target flow measurement system is established. Through the flow experiment, we can get the flow test result. The experimental data error analysis can be concluded to verify the feasibility and precision of the design.
Investigations of dielectric gratings using electrodynamic models based on volume integral equations
Eigenmodes of planar and cylindrical dielectric gratings (DGs) and electromagnetic wave scattering from multiplayer DGs are investigated. The DG characteristics are calculated using numerical-analytical solution of integral equations (IEs).