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Документ Practical aspects modeling of air conveying modes for small–piece food products(2020) Kryvoplias-Volodina, Liudmyla; Gavva, Oleksandr M.; Yakymchuk, Nikolai; Derenivska, Anastasiia; Hnativ, Taras; Valiulin, HennadiiA mathematical and physical model of the critical pneumatic conveying modes has been developed to ensure the calculation and construction of pneumatic product pipelines of continuous operation. The model takes into consideration the technological conditions of gas suspension movement; the laws of movement of individual fine particles, accounting for their impact interaction and decompression, as well as the actual boundary conditions for a food product movement. The parameters of the zone of dynamic destruction of the layer of a small-piece food product by impact airwave were experimentally studied; the results of the calculation have been compared with the experimental data. The process of managing critical pneumatic conveying modes has been theoretically described, based on the proportional elements and feedback (a current loop of 4‒20 mA); the process of destruction of the cluster of products by airwave and controlled decompression has been studied. The process of pneumatic conveying of a small-piece product at the experimental bench system has been examined. As well as the process of moving the material in the product pipeline, which is controlled by compressed air pulses, to maintain the modes of operation. The following has been established: pressure losses caused by the movement of clean air; additional pressure losses resulting from the movement of the material; the loss of pressure required for transporting in a suspended state on a vertical stretch. A model has been developed to calculate the coordinates of a product particle when it collides with the inner surface of the product pipeline, as well as a change in its kinematic characteristics. The developed model makes it possible to determine the rational modes of pneumatic conveying and possible energy costs in the processing of various small-piece materials. The rational pneumatic conveying regimes have been determined, as well as possible energy costs in the processing of small-piece materials. As the time of supplying compressed air in the product pipeline increases, the number of product particles reaches a maximum in the range of 0.1...0.2 s. The compressed air flow rate, depending on the value of inlet mainline pressure P (0.1…0.3 MPa), is 80…160 (Nl/min). A general approach to the modeling of pneumatic conveying systems has been proposedДокумент Dynamics of mechatronic function modules drives of flow technological lines in food production(2018) Kryvoplias-Volodina, Liudmyla; Gavva, Oleksandr M.; Volodin, Sergiy; Hnativ, TarasThe tasks were considered, which are related to the working bodies for the artificial food products movement according to the specified movement law and their positioning in the intermediate positions of the kinematic cycle.Materials and methods. The actuators dynamics characteristics and control system of power part of positional electro-pneumatic actuators were researched. The methods of mathematical and computer modeling, and methods of solving ordinary differential equations and partial differential equations and method of correlation analysis were used. Results and discussion. The analytical dependences for determining the kinematic parameters of the artificial product movement with the mechanism of collision, which is based on the pneumatic actuator, are obtained. The dynamical model of the actuator is mathematically tested and the movement law of the collision mechanism, which is approximated to the optimal speed, is obtained. To analyze the loading process of the working link of the positional actuator, the model of a generalized control system is used, which is limited by the one full cycle of operation of the functional mechatronic module of the packing machine. Such a model allows to describe the overload process, both in the case of full and partial filling of the working cycle. This is important when packing products in different geometric shapes of consumer packaging, which is typical of modern packaging machines. The simulation model of the actuator is theoretically substantiated and confirmed, which has a number of advantages, unlike the existing structures of positional drives in packaging machines. Сalculated difference, during mathematical modeling, of the value of the working time of the output stage of the functional mechatronic module for the processing of the kinematic cycle of the operation of the packaging machine was for the various input parameters of the limit to 7%. The results of the mathematical modeling of dynamics for a positional pneumatic actuator, with the condition of changing the cross section of the exhaust hole, gave the opportunity to obtain the kinematic characteristics of the drive. Conclusions. The results of mathematical modeling for positional pneumatic actuators with the condition of changing the section of the exhaust hole allowed to track all the kinematic characteristics of the actuator.