developed this method on an aircraft leading edge structures, and the experimental results confirmed the advantages of this method in the aspect of the less power consumption and the relatively light weight. Kandagal and Venkatraman used piezoceramic actuators to induce vibration in a flat plate, the de-icing experiment was successful at resonance frequencies at which the peak values of shear stresses exceeded the adhesive shear strength values of ice on the plate. The latter method is studied in this work. One stimulates the actuator at ultrasonic frequency range, and the other induces the resonance of structures at much lower frequency. The global research on de-icing by piezoelectric actuators can be divided into two categories. Based on this conclusion, a vibration method with piezoelectric actuators is carried out to de-ice in a softer and efficient manner. The research on the adhesive properties of ice indicates that the adhesive strength of ice is much lower in shear than in tension. Among the prevalent surface deformation systems, some have to change the outer surface of the wing, and others produce strong forces to destroy the adhesive strength of ice, which present a threat to the fatigue of the skin. The ice cracks and debonds from the deformed surface, and the particles are carried away by the aerodynamics force. The surface deformation systems are developed to reduce the amount of energy required for de-icing. Freezing point depressants have a low power demand, but the weight brought by the huge demand for certain chemistry fluid limits its usage on in-flight de-icing compared with its application on the ground. De-icing by thermal melting is a well-developed and commonly used technology while its high power requirement is a significant disadvantage. The de-icing methods consist of freezing point depressants, thermal melting and surface deformation according to their mechanism. Icing problems bring serious security threats and potential economic losses to the aviation, thus efficient de-icing methods are in urgent demand. The ice will distort the smooth flow of air over the wing, resulting in the reduction of the wing’s maximum lift and the critical angle of attack leading to a stall, as well as significantly increasing drag and adversely affecting the handling qualities of airplanes. When the aircraft flies through clouds containing “super-cooled” liquid water droplets, icing is likely to occur on impact. The power consumption for vibration de-icing is about 36.5 w/m 2, which is only 1.57 % of the power consumption when using the latest electro-thermal de-icing method.Īircraft icing is one of the major hazards to aviation. Finally, experimental investigations on a clamped aluminum plate are carried out to verify the results of the analysis. Actually the optimal length would be a slightly longer due to the influence of the actuator. For a specific mode the maximum excitation happens when the length of piezoelectric actuator is an odd integer multiple of the half wavelength of that mode. The results indicate that peak values of the shear stress at the interface appear at the edges of the ice, and the amplitudes depend upon the strains on the surface of plate underlying the edges of ice. The optimal length is determined in order to maximize the shear stress. ![]() The finite element method (FEM) is used to get the relationship between the length of piezoelectric actuator and the vibration intensity of the modes to be excited. A shear model of linear Bernoulli-Euler type is derived with ice attached to a flat plate, which is capable of predicting the shear stress along the interface and gives guidance to the choice of vibration modes for de-icing. The vibration induces shear stress at the interface of the ice and structure, which leads to the shedding off of ice. The maximum displacement of the structure will be achieved when excited at the natural frequencies. This work presents the analytic and experimental research of a vibration de-icing method for aircrafts with piezoelectric transducer as the actuator.
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