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Polymeric coatings and packaging are often used to enhance the temperature sensitivity of fiber Bragg grating temperature sensors. The high thermal expansion coefficient of the polymer enhances the thermal sensitivity by improving the wavelength shift due to thermal expansion. The adhesion of the polymeric coatings to the silica based optical fiber plays an important role in the wavelength response characteristics of fiber Bragg gratings with respect to temperature. Experiments are done to qualitatively analyze the influence of adhesion. Three‐dimensional finite element simulations have been carried out. Spring elements are used to interconnect the nodes of the meshed models of optical fiber and coating. The effect of adhesion is studied as a function of spring stiffness.

The purpose of this paper is to analyse an actual representation of ice accretions, which are important during the certification process.

Ice accretion experiments are conducted in a low-speed subsonic wind tunnel testing facility to evaluate the influence of various ice shapes around the airfoil sections. Ice accumulation changes the shapes of local airfoil sections and thereby affects the aerodynamic performance characteristics of the considered NACA 23012 profile. The ice profiles are impregnated using balsa wood with glace, horn and mixed ice accretion cases for the detailed experimental investigation.

Computational fluid dynamics analysis is done to compute the influence of different ice shapes on the aerodynamic coefficients (C_l and C_d) while ice accretion occurs at the leading edge of the airfoil sections. It is observed that the C_l and C_d modified immediately more than 40% as compared to the clean wing configuration. In the same fashion, the skin friction coefficient also abruptly changes for different ice shapes that have the potential to induce flutter at the critical speed of the airplane. The computational solutions are further validated through wind tunnel experiments and recent literature concerning certification for flight in icing conditions.

The ice accretion study on the aerodynamic surfaces can also be extended for wind turbine blades installed at different cold regions around the globe. Further, the propeller icing influences the entire rotorcraft aerodynamics at low temperature conditions and the findings of this study are strongly connected with such problems.

The aerodynamic characteristics of the baseline airfoil are greatly affected by the ice accretion problem. Although flight through icing condition endures for a short duration, the takeoff path and decision speed are determined based on airplane drag as per federal aviation regulations. Hence, the proposed study is focussed on a cost-effective approach to predict the effect of ice accretion to achieve optimum performance.