MODELING OF HEAT-PHYSICAL PROCESSES IN SOLAR DRYERS

Abstract – In this article, the process of a solar drying installation is described thermophysical characteristics and their design formulas in the possibility of an algorithm of mathematical modeling.

JOURNAL OF CRITICAL REVIEWS

I.Introduction

A sharp increase in energy demand will lead to the use of alternative energy sources. The relatively low efficiency of power plants operating with such energy sources complicates their use. The growing population of the world is also leading to an increase in demand for dried food products. The role of solar dryers in the uninterrupted supply of dried food to the population is invaluable. Solar dryers mainly consist of a transparent layer, air circulation openings, space for the product to be dried and walls. The working principle of the dryer is that sunlight passes through a transparent layer and is absorbed by the indoor air as well as the drying elements. The absorbed energy is converted into heat. The dryer temperature is formed due to this energy. An inflow of low-temperature air from the lower slits of the device enters the dryer; the temperature rises and at the same time evaporates the moisture of the product intended for drying from the upper slits.

II.Literature review

Research in the field of design and improvement of solar dryers has been conducted by many scientists. So far, no perfect devices have been created among the solar dryers created. There are some devices whose performance has improved due to the design. There is no single device that combines the performance of all the devices created. There is a need for such devices today. Fruits and vegetables grown in Uzbekistan are distinguished by their unique taste. Therefore, the similarity of dried fruits and dried vegetables made from them is not found in the world market. Therefore, such products are in great demand in the world market.

III.Analysis

The development of effective solar fruit dryers and its implementation requires the study of heat-mass exchange, thermal-physical processes that occur during the drying of fruits. Determining the construction mode of each fruit dried in dryers, the study of construction kinetics, technological processes related to the quality of dried fruits is one of the current tasks. The quality and appearance of the dried product (moisture-heat regime of the dryer) depends not only on the drying modes of the fruit, but also on the technology of pre-treatment and drying of the fruit before drying. In the mathematical modeling of the thermal regime of solar dryers, we write the heat balance equations for each element of the system under consideration (Figure 1): Learn more...