Experimental measurement and analytical method for critical temperature of aircraft icing detection failure

In modern aircraft, the icing detector is incorporated into the ice protection system (IPS) to determine if the aircraft is in an icing environment, thereby enabling the IPS to activate promptly when ice forms on the wings, engines, etc. Regardless of the type of icing detector used, certain unique flight conditions can result in ice accumulation on wings or engines before detection by the device, thereby delaying the identification of icing events and compromising aircraft safety. To mitigate the risk of icing detection failure, aircraft must operate in environments above the critical icing detection temperature. However, within the icing envelope, capturing the critical temperature has traditionally been a challenging task. This paper addresses this issue through a combination of ice wind tunnel experiments, numerical simulations, and theoretical analysis, a novel and rapid method for calculating the critical temperature is presented. Current research involves the experimental measurement of critical wing temperatures in an icing wind tunnel, revealing that icing detection failures occur under flight conditions with a large angle of attack. Additionally, a numerical model has been developed to calculate the critical temperature, and its results align well with experimental data. However, due to the high computational cost of numerical simulations across a wide range of icing conditions, this paper proposes an analytical method based on the principle of thermal equilibrium. This method rapidly predicts the critical temperatures of the probe and wing, achieving a deviation of less than 10% between the analytical and experimental values.