| Abstrakt: |
It is known that the physical and mechanical properties of raw cotton stored in a riot change over time. It is known that the physical and mechanical properties of raw cotton stored in a riot change over time. It has been established that due to changes in kinetic and biological processes, the internal temperature of raw cotton is distributed according to a non-linear law. As a result of such processes, a slight change in temperature leads to a qualitative change in the physical properties of cotton. Therefore, mathematical modeling of the conditions of storage of raw cotton in bunt is of great importance. In the authors' scientific article [1], a one-dimensional mathematical model of temperature distribution in raw cotton was developed. The results obtained shows the temperature distribution along the height of the cotton riot changes according to a linear law. This change in the initial layers obeys a stationary law (for o7m) the temperature rises. The temperature at the top of the bunt is the same as the outside temperature (16℃-20℃), and the bottom layer is around 28℃-32℃. Because the heat transfer coefficient of raw cotton is relatively small in the upper part of the bunt, and large in the lower layer. At the same time, raw cotton is heated in the lower layers, which negatively affects its quality. In such cases, appropriate measures must be taken to prevent overheating. In this scientific article, a two-dimensional mathematical model of temperature changes in raw cotton was considered based on Laplace's law of heat transfer. Based on the two-dimensional model, a differential equation representing the non-stationary heat flow distribution law was established. Differential equations was transformed into algebraic equations by the finite difference method in a grid-space-time coordinate system in a discrete sequence. These equations were numerically solved using MAPLE-17 software. Graphs of temperature changes over time in horizontal and vertical layers of cotton were obtained. It was found that the temperature change in the horizontal direction along the vertical layers from top to bottom is linear. With the transition to the lower layers, the transition of the temperature to a non-linear state was observed. As a result, it causes a spontaneous increase in temperature in the middle of the lower part of the cotton layer. This situation deteriorates the natural properties of cotton. [ABSTRACT FROM AUTHOR] |
