A novel fiber-optic ice sensor capable of identifying ice type accurately

This paper introduces a novel fiber-optic ice sensor with a differential structure of dual signal fiber bundles and an oblique end-face of fibers, not perpendicular to the axis of the optic fiber. An experimental facility to simulate aircraft icing on the sensor and measure the ice thickness was set up and used to measure the ice-growth curves for different types of ice accreted at different temperatures. The curves turned out very distinct from each other. With increasing ice thickness, the output voltage of the sensor would reduce rapidly for glazed ice, increase rapidly for rime ice, and make no remarkable change for mixed ice. These different trends were attributed to the different optical intensity distributions in the fibers for different ice types, which can be used to reliably identify the ice type and accurately measure the ice thickness. This fiber-optic ice sensor can be of great value in direct ice detection for aerospace applications.

► We propose a novel fiber-optic ice sensor with an oblique end-face of fibers.
► Ice-growth curves quite differ from each other for glazed, rime and mixed ice.
► Optical intensity distributions change with ice type.
► The sensor can reliably identify the ice type for aerospace applications.