Nauka ta progres transportu (Oct 2014)
THE BASIS OF RESONANCE-STRUCTURE THEORY FOR VIBROIMPACT UNLOADING OF THE VEHICLES
Abstract
Purpose. The use of the main provisions of the resonance-structure theory for theoretical study of basic physical and mechanical processes taking place in unloading material during the vibrimpact discharge in order to substantiate the efficiency of their application. Methodology. Unloading material during vibroimpact unloading, as the study object, appeared as phenomenological model of spatial dispersion medium. The dynamics equations of unsteady forced particle oscillations of the "linked" structure under the action of vibration and impact loadings, taking into account the vibro rheological effect, with the establishment of resonance zones were considered. Findings. When considering the resonance zones of unstable forced oscillations of the "linked" structure particles it was found out that under the influence of vibration loadings the system is effectively affected by the monoharmonic pulse of external forces in the form of sinusoidal wave with an angular frequency. This frequency is equal to the main frequency of the natural oscillations of the unloading material. Under the impact loading it is necessary to affect the system by the accumulation of external force pulses in the form of single instant impulse. Under the given load conditions in these systems the phenomenon of resonance, which provides absolute deformation in handling system of the "linked" structure of the material due to discrete growth in the range of plastic deformations takes place. Absolute deformation, resulting in handling material exceed the permissible elastic deformations for the particles of this system and the destruction of the contact zones of these particles takes place. Originality. The authors studied unstable forced oscillations of the "linked" structure particles based on the phenomenological model of the spatial dispersion medium of unloading material. Thus, for each type of vibro-impact loads were calculated the conditions for resonant processes. That was presented by the relevant type of the actuating force. Practical value. The main provisions of the resonance-structural theory in theoretical study of the vibroimpact load processes prove the use efficiency of the vibroimpact equipment to increase the intensity of the vehicles unloading. The use of resonance-structural theory allows predicting the required parameters of vibro-impact loading on the unloading material, depending on its physical and mechanical properties that ensures the efficient unloading due to the destruction of the power relations of unloading material particles.
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