Numerical and experimental characterisation of an aeronautic Pitot probe

Abstract

Aeronautic Pitot probes (PPs) are extremely important for airspeed and altitude measurements in aviation. Failure of the instrument due to clogging caused by ice formation can lead to dangerous situations. In this work, a commercial aeronautic PP was characterised experimentally regarding its inner composition, material properties and its thermal performance in a climatic wind tunnel. Performance runs were taken out in order to analyse the thermal response of the PP under various operating conditions with a particular emphasis on the cooling process in the case of a heating element failure. Data for the thermal conductivity, diffusivity and specific heat for each material forming the PP were obtained. A numerical model to simulate the thermal behaviour of the PP was created using Comsol Multiphysics (CM). Experimental data were compared with their numerical counterparts for model validation purposes. After the model was validated, the operation of the PP in flight conditions was simulated. The failure of the conventional heating system was analysed to obtain the time until the PP reaches a tip temperature where ice formation can be expected. The tip temperature undercut the zero degrees Celsius mark 165 seconds after the heating element was switched off. The data collected in this work can be used to implement and validate mathematical models in order to predict the thermal performance of Pitot probes in flight conditions.

A cumulative exposure model for remaining useful life prediction of pitot tube based on dynamic operating data

“…For reliability‐related issues of PT, a numerical model using Comsol Multiphysics (CM) was created to simulate the thermal behavior of the PT by Jäckel et al., which used the data to predict the thermal performance of PT in flight conditions 5 . The studies by Wajih Ezzeddine et al.…”

“…4 For reliability-related issues of PT, a numerical model using Comsol Multiphysics (CM) was created to simulate the thermal behavior of the PT by Jäckel et al, which used the data to predict the thermal performance of PT in flight conditions. 5 The studies by Wajih Ezzeddine et al have defined the hazard and reliability function based on Coxs proportional hazard model to determine the optimal preventive maintenance policy for the PT system. 6,7 In later work, he also proposed an algorithm for a periodic inspection strategy for multi-unit irreparable systems like PT, and derived a regression model based on k-out-of-N system estimation algorithm to determine the effect of internal and external conditions on the operating state.…”