نوع مقاله : مقاله پژوهشی
1 دانشگاه صنعتی نوشیروانی بابل
2 دانشکده مهندسی مکانیک، دانشگاه فردوسی مشهد
عنوان مقاله [English]
In the present work, the effect of smart shape memory alloys on thermal buckling and post-buckling of monoclinic and unidirectional composite panels has been investigated. The aerodynamic pressure applied to the system was modeled using the piston theory method and also the effect of thermal heating for ultrasonic flows was estimated from the reference temperature method. The panel is modeled nonlinearly with large deformations based on Van Karmen theory. The obtained results show that the shape-memory alloy was able to increase the critical temperature of thermal buckling. The effect of the arrangement of composite layers on increasing the thermal buckling temperature was also studied. The results show that the amount of thermal deflection is greatly reduced due to the use of this alloy. Also, in the higher temperatures differences, the rate of reduction of the panel is increased.
In this work, the effects of thermal stress on buckling and thermal buckling in a rectangular composite panel with hinge-hinge boundary conditions were investigated. Also, the effect of shape retention alloy in controlling these two phenomena has been studied. The shape memory alloy wire was placed in martensitic mode to apply a compressive force to the panel to control the heating and aerodynamic forces after changing the phase to austenite. The governing equations of the system were extracted through the layer theory method in order to better show the effects of in-plane displacements.
Investigations on the effect of different layers (symmetry effects and arrangement angle of composite sheets) were performed to investigate thermal buckling. According to the obtained results, the layer arrangement of plates (0.90 / 0.90), (-45.45), (30/60), and (0.90 / 90), respectively, had the greatest effect on raising the critical temperature of thermal buckling in Dimensional ratios are equal to or greater than one. This shows that the symmetry of the arrangements has a greater effect than the angle of the arrangements. Examining the buckling diagrams for the effect of a shape memory alloy, it can be concluded that by placing this alloy in the composite panel, in addition to raising the buckling temperature, this alloy has a greater effect on the displacement control by increasing the temperature after the critical buckling temperature.