Knowledge of the gas flow distributions, their mass velocity and turbulences, in chemical reactors, thermodynamic
engines, pipes, and other industrial facilities may help to achieve a more efficient system performance.
In our novel approach, optical fibre Bragg grating (FBG) sensors have been used for measuring the temperature of a
heated element, adapting the principles of conventional hot-wire-anemometers. Because of the multiplexing capability
of FBG sensors, the gas mass flow distribution can be measured along the sensor array. The length of the heated and
sensor-equipped element can be easily adapted to the cross section of the gas flow, from <10 cm up to several metres.
The number and distances of FBGs distributed over this length defines the spatial resolution and is basically limited by
the sensor signal processing. According to FBG sensor lengths < 5 mm, spatial resolutions of gas flow measurements of
less than 1 cm can be achieved.