Quantitative analysis for the effect of the thermal physical property parameter of adhesive on the thermal performance of the quadrupolar fiber coil.

As a high-precision angular sensor, the fiber optic gyroscope (FOG) usually shows high sensitivity to disturbances of the environmental temperature. The thermal performance of the FOG will be directly affected by the selection of adhesive for adhesion inside the fiber coil, however, the current research on this is very rare. This paper is focusing the question above; firstly, the influence mechanism of temperature and stress on the non-reciprocity phase difference of the fiber coil is analyzed, and a model of fiber coil thermal-induced drift error is built. Secondly, the fiber coil three-dimensional simulation model including fiber core, coating layer, adhesive and various materials is built, and the accuracy of the model is verified by simulation and experiment. In the end, the influence of six thermal physical property parameters of adhesive material on the thermal performance of the FOG is analyzed quantitatively and the degree of influence from high to low is Young's modulus, Poisson's ratio, specific heat capacity, density and thermal conductivity. Results show that when choosing the adhesive, decreasing the thermal expansion coefficient, improving the young's modulus, reducing the poisson's ratio, reducing the heat capacity, reducing the density and increasing the thermal conductivity within a certain scope will be conducive to inhibit thermal-induced error of the FOG. And further prove that, the thermal stress distribution inside the fiber coil has more influence on the thermal performance of the FOG than the temperature field distribution. These findings are very helpful to chose and produce adhesive of fiber coil and improve the thermal performance of FOG.