Research In Physical Property Testing Method Of Aeronautic Porthole Assembly

Because of its excellent optical performance, intensity, temperature andaging resistance, for a long time aeronautic PMMA has been used as the mainmaterial of airframe transparency, like aeronautic porthole. With the continuousimprovement of modern airplane performance, the increasingly complicated flightenvironment provides a much stricter requirement for the material property ofporthole glass. The porthole glass’s property has a direct impact on the normaloperation of airborne equipment and the safety of its flight crew. At present theresearch in aeronautic PMMA is mainly the mechanical property testing, such as thetensile testing under different temperature loads, whose testing environment has a bigdifference with the real flight conditions, and its research object is merely focused onthe own property of aeronautic PMMA. Therefore, based on the analysis of materialproperty and flight conditions, in this paper a physical property testing method foraeronautic PMMA based on temperature-pressure parameters was put forward. Themain work was as follows:1) The material property of aeronautic PMMA, the structure of aeronauticporthole, and flight conditions were analyzed. Based on present testing and studymethod a physical property testing method for aeronautic PMMA based ontemperature-pressure parameters was proposed, and its hardware was designed.2) The mathematical models of adiabatic gas charging and discharging systemwere built, appropriate pressure-control algorithm was designed, and then thepressure-control part of aeronautic porthole assembly testing system was studied byco-simulation based on AMESim and MATLAB/Simulink. The simulation resultdemonstrated the tracking control of system pressure could be realized effectively bythe proposed pressure-control system and its fuzzy-PID control algorithm, whosestatic and dynamic performances were both better than conventional PID controlalgorithm.3) The testing system’s software design was completed, and the study ofexperiment for different testing materials by this testing device was carried out. The curves of temperature, pressure and deformation showed the performance of thetesting system met the design requirement, and proved the feasibility of this testingmethod.