Abstract

Currently, the environment is saturated with physical fields of different nature, one of which is acoustic. It has both a positive and negative impact on living organisms. A special case is the coincidence of the resonant frequencies of individual organs with certain frequencies of the acoustic fields, which leads to negative effects at high values of the oscillation amplitudes. This determines the relevance of the selected theme of research. A study was made of the acoustic and mechanical characteristics of the strength of living bodies, which led to the conclusion that it is possible to exert a detrimental effect on the bodies of the larvae of harmful insects with acoustic fields. To realize a negative acoustic effect on the bodies of insect larvae, it is necessary to know the mass, stiffness and resonance frequency of these bodies. A technique for determining the resonant frequency of the larvae of harmful insects has been developed. The research is based on the assumption that the shape of the body of the larva is close to the shape of a homogeneous cylindrical shaft. The bodies of larvae are loaded in a special device. The processing of experimental data made it possible to calculate the elastic modulus and rigidity of the body of the larva. The obtained values of the resonant frequencies are in the range from 5.2 to 8.8 Hz. These data made it possible to determine the frequency tuning of the acoustic radiation intended to destroy the larva. Having carried out calculations in the ANSYS software environment and comparing them with the results of full-scale tests, it is defined that the value of deformations differs approximately by 2-3 times, and the resonant frequency by approximately ± 10% during the experiment and during simulation. The discrepancy in the results is due to the fact that the ANSYS software environment calculates deformations by the finite element method more accurately, while a large error is based on the experimental data. The possibility of destructive effect on the bodies of harmful insects larvae by acoustic fields is determined on the basis of data dealing with their mechanical characteristics. The simulation of the experiment in the ANSYS software environment was carried out.

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