Laser-optical fiber Bragg grating anemometer for measuring gas flows: application to measuring the electric wind

Abstract

A novel laser-optical fiber Bragg grating anemometer (FBGA) has been devised for measuring the speed of a moving gas in the range 0-1.5ms‑1. As a test, the FBGA was applied to measuring the speed of the electric wind generated in the particularly harsh, high-voltage environment of a dc, negative-polarity, partial (corona) discharge in atmospheric air. The instrument proved more stable and yielded an order-of-magnitude improvement in sensitivity (Δv≈4×10‑3ms‑1) compared with other optical-fiber-based anemometers. On-axis wind speeds ranging from zero to 1.1ms‑1 were measured in the vicinity of the corona discharge.