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Vapor–liquid flow in a cylindrical channel through fillings of spherical particles is studied experimentally. Data on the critical flow of a vapor–water mixture with various vapor contents through densely packed layers of spherical particles from stainless steel with diameters of 2 and 4 mm for a filling column height of 250 and 355 mm are obtained. Experimental data demonstrate the influence of pressure, the vapor content of the mixture at the input, and the geometric parameters of the filling on the critical mass velocity. The linear dependence of the critical mass velocity on the geometric factor \(\sqrt {d/H} \). The possibility of generalizing the experimental results based on the gas dynamic model for the flow of a homogeneous medium is considered.

The work investigates the process of making chips from carrot root crops. Now fruit and vegetable chips are very popular due to their high concentration of nutrients which significantly increases the calorie content, biological value and assimilation of the product. The lowered moisture content provides the chips with good preservation of concentrates for a long time. Experimental studies were carried out on an experimental infrared drying plant, developed by the staff of the Department of Power Supply and Heat Power Engineering of Irkutsk State Agrarian University. Drying of carrots was carried out in an oscillating mode “heating - cooling” which allows intensifying the drying process and shortening its duration. Recording results on the change in weight and size of carrot slices along the length was carried out every ten minutes. Based on the data taken it was done graphs of the relative mass dependence from the time of infrared drying and we presented the results of studies on the shrinkage of chips.

The article considers the heat treating process of edible vegetable raw materials in the system “emitter - material” as the simplest case of heating and drying a homogeneous and isotropic body. It is accepted that the cooling conditions, the ambient temperature and the heat transfer coefficient in time remain constant, and there are no internal heat sources. Based on the study of the fundamental works of famous scientists in the field of food drying, the problem of determining the time constant of raw material heat treatment is solved. This parameter during heat treatment directly depends only on the physical properties of the material, the cooling process on its surface, geometric shape and body size. Knowing the values of the heating time constant, it is possible to determine the time and speed of heating the material to a given temperature.

The purpose of these studies is to create an automated system for the drying process of agricultural raw materials. This system should be capable of providing biotechnological conditions for heating a single product to preserve especially valuable biological components in this product. Environmental problems of modern society determine the objective of functional nutrition of a person, as the basis of a healthy lifestyle. To solve this problem, it is necessary to obtain products of high nutritional value, with a maximum content of active substances. Each plant product contains not only vitamins and minerals, but also elements that determine its special value. During storage, these components are lost due to biological characteristics and storage conditions. To preserve them for a long period and create a product of high nutritional value, certain conservation methods must be used. Such methods include drying. Products dried in a special way are able to maintain up to 95% of their valuable indicators. An analysis of modern drying methods for plant raw materials showed that the pulse infrared-convection method more closely meets the requirements of biotechnological heating conditions and is therefore suitable for obtaining products of high nutritional value. This method has a sterilizing effect, which allows to increase the shelf life of finished products. The creation of an automated control system for pulse infrared - convection radiation made it possible to obtain products of high nutritional value for long-term storage.