Probabilistic Model of the Reflectivity of Construction Materials of the Agroindustrial Complex

When developing modern lighting technologies for objects of the agro-industrial complex, the problem arises of assessing the contribution of reflected light to the normalized illumination. The reflective properties of the surfaces of materials are characterized by a reflection coefficient ρ, which reaches a value of 0.7. This allows us to consider the reflective surfaces as an additional light source and the possibility of reducing energy consumption costs. (Research purpose) The research purpose is in developing a mathematical model that allows us to estimate the spectral reflection coefficient ρ(λ) of materials of construction technologies of the agro-industrial complex in the ultraviolet and visible spectral regions. (Materials and methods) That the disadvantage of various models is the lack of an analytical method for calculating the reflection coefficient in a wide range of wavelengths. We used a probabilistic method to overcome this disadvantage. (Results and discussion) The developed mathematical model makes it possible to estimate the reflection coefficient of the rough surface of materials in a wide range of the spectrum. For concrete, the area of agreement between theory and experiment is in the wavelength range from 250 to 1000 nm. The saturation mode predicted by the theory (the independence of the reflection coefficient from the wavelength) at a reflection coefficient of 0.4 is consistent with the experimental values in the visible range of the spectrum for construction materials of the agro-industrial complex, in particular, gray textured concrete, gray facade paint, light wood, gray silicate brick, new plaster without whitewash. (Conclusions) In the case of normal light incidence, the developed mathematical model allows us to theoretically estimate the reflection coefficient of the rough surfaces of construction technologies of the agro-industrial complex. The proposed model can be used in the development and design of a system of technological lighting of large-area premises (for example, when keeping birds on the floor), as well as for developing recommendations for reducing the energy consumption of existing lighting systems.

Installation with a Temperature-Controlled Panel for Piglets

Agricultural enterprises include engineering systems to ensure the vital activity of animals. The effectiveness of such systems is determined by the possibility of creating the required conditions in places where animals are kept in interaction with external temperature parameters of the habitat. (Research purpose) The research purpose is considering the physical and thermodynamic models of the thermal regime of the heated site and developing a structural scheme, a method for calculating the installation of heating sites for piglets using thermo-electricity. (Materials and methods) The article describes models of the combined thermal regime in a biotechnical system. The layout and structure of the technical system of thermal stabilization with the use of thermoelectric modules were considered. The article presents the relations between the technical elements included in the biotechnical system and the boundary conditions for the existence of such a system. (Results and discussion) The contact heating method is characterized by high technological efficiency. When young animals are located on a surface heated to the required temperature, the outflow of heat from the animal's body to the floor decreases, hypothermia of vital organs is prevented. The normal vital activity of the animal is possible within a limited range of the surface temperature of the sites in the places where they are located, the temperature factor acts as the determining factor. Depending on the environmental conditions and the duration of the growing cycle, it is necessary to generate a certain level of thermal energy in the thermodynamic system "animal-environment". The article justifies the use of certain installations and the creation of a technical system that ensures the maintenance of comfortable conditions for the maintenance of young animals. (Conclusions) The method of regulating the thermal regime with the construction of an effective thermal stabilization system can be based on the use of thermoelectric modules. The article presents the operating modes and load characteristics of a specific thermodynamic module in the space of variable parameters that display the areas of change of individual factors included in the mathematical model. Based on the results obtained, we concluded that the module is capable of working in this application.

Modeling and Analysis of Lightning Protection in an Emergency Situation of a Lightning Strike

The grounding of the supports determines the resistive, the most significant component of the overvoltage acting on the insulation gap between the lightning rod and the equipment of the electrical substation when lightning strikes the lightning rod. (Research purpose) The research purpose is in developing recommendations for the grounding devices for lightning rod supports and means of suppressing sliding spark channels in a multi-wire system. (Materials and methods) The estimation of the share of lightning current in the grounding conductor of the lightning rod support can be calculated simplistically. This makes it possible to abandon the solution of long-line wave equations and switch to a substitution scheme with concentrated parameters, in which the active and inductive resistances of sections of an electric circuit loaded with lightning current should be considered, with mandatory consideration of inductive connections between them. (Results and discussion) The article presents the calculation for a pulse with an oblique front and a flat head, which is traditionally used to estimate the number of reverse overlaps on an overhead power transmission line when a lightning strike hit a support. It was assumed that the lightning strike occurred in the extreme thunderstorm, the current load mode of which is the least favorable. The greatest current load of the grounding conductor of the support corresponds to a direct lightning strike, when the current amplitude there differs from the current amplitude of the first component in the lightning channel by no more than 25 percent, this mode should be taken as the calculated one when estimating the maximum length of the sliding spark channel. (Conclusions) The maximum lengths of sliding spark channels in soils of different conductivity were determined using computer modeling of an emergency situation of a lightning strike, provided that the reinforced concrete foundations of the lightning rod supports connected by an underground horizontal bus are used as grounding conductors of lightning rods. The most effective means of limiting the danger of sliding spark channels is their forced orientation to the side, which is safe for the grounding circuit of an electric substation.

The Three-Factor Experiment on Microwave Micronization of Grain Feed

To obtain the most reliable information about the object of research with minimal time and financial costs, it is necessary to search for a rational sequence of data collection on the characteristics of micronization of grain feeds. (Research purpose) The research purpose is in conducting experimental studies of UHF micronization of grain feeds. (Materials and methods) The article presents a full factor experiment as the method of planning and conducting the experiment, this method serves to find the optimal conditions and rules of processes occurring during ultrahigh-frequency processing of grain feed raw materials. Micronization was carried out in the developed installation, which provides the addition of magnetron powers to reduce the cost of the installation and the operating costs of micronization. Authors conducted experiments on feed barley of the second production class. During the experiment there was used the grain moisture meter "Fauna-M", ultra-high-frequency magnetron generators 1 kW Daewoo M 218 and caliper ShTs-1. (Results and discussion) A complete three-factor experiment was performed, as a result of which the influence of design parameters and installation modes on the properties of grain feed was studied on the example of feed barley when adding the magnetron powers in the device. The article presents experimental data on the measurement of the exchange energy content in samples of feed barley grain. Its increase was revealed, which is the main physical and chemical characteristic of the process of micronization of grain feed. (Conclusions) The article presents optimal ratios of variable essential factors, compliance with which can contribute to an increase in the exchange energy content in feed barley grain samples from 12 to 13.1 megajoules per kilogram: humidity of 16.5 percent, the power level of the second device, the height of the radio-transparent end of the waveguide relative to the grain layer level of 41.7 millimeters.

The Potential of the Russian Federation and Uzbekistan for the Implementation of Solar Renewable Energy Systems

The main drawback of the modern power supply system is centralization. Renewable energy is a promising alternative for supplying electricity to remote settlements. Solar energy is more preferable, since it is least dependent on the geographical location. (Research purpose) The research purpose is in studying the possibilities of creating an autonomous renewable energy system based on solar photoconvertors for remote villages. (Materials and methods) Authors examined small rural settlements in various climatic regions of the Russian Federation and Uzbekistan, identified promising regions for solar-powered systems similar in climatic and socio-economic parameters – the Krasnodar Territory and the regions of Uzbekistan. There was used data from the NASA POWER project for analysis. (Results and discussion) The article presents the comparison of a diesel generator and a renewable solar-diesel system as an autonomous source of electricity for small settlements. Due to the lack of sun in winter and due to lower temperatures, there is a need for an additional source of energy. (Conclusions) The article presents the methodology for assessing the technical and economic potential of renewable energy sources in the regions under consideration. Due to the high solar activity and geographical location, the cost of energy in the regions of Uzbekistan was 0.153, 0.155, 0.166 dollars per kilowatt-hour for hybrid renewable energy systems and 0.387, 0.371, 0.401 dollars per kilowatt-hour for a diesel generator. In the Krasnodar Territory these costs are 0.138 dollars per kilowatt-hour for a hybrid system and 0.316 dollars per kilowatt-hour for a diesel generator. It is possible to create fully autonomous power supply stations in these regions based on solar energy stations. For this purpose it is necessary to add an energy source that will be used during periods of insufficient solar activity. The most promising solution is the use of a wood gas source.

Development of an electromagnetic device for studying the electrophysical properties of agricultural products

The problem of control and quality of agricultural products is relevant for agro-industrial production. To determine the quality indicators, for example, milk, various indirect methods are used, but they are complex, some require special preliminary preparation of the sample. We need methods that will meet the following requirements: simplicity, speed and mobility. The identification of the electrophysical properties of biological objects can become the basis for the development of an electromagnetic method that will meet the above conditions. The article considers processes based on a change in the voltage (output signal) of a parallel oscillatory circuit in which an inductive cell contains the studied agricultural products. (Research purpose) The research purpose is in developing a device for determining the electrophysical properties of biological objects, analyzing the results of the study, obtaining the dependences of the output signal of the resonant amplifier on the frequency of the generator. (Materials and methods) The article presents studies of the resonant processes occurring in the simplest parallel oscillatory LC circuit. The article analyses the effect on the output parameters of a parallel oscillatory LC circuit when its inductance changes by placing various substances in an inductive coil. (Results and discussion) The article presents a block diagram of an electromagnetic device for determining and studying the electrophysical properties of biological objects. The block diagram is implemented directly into an electromagnetic device. Authors created a program in the MATLAB package for processing the experimental data. Based on the results of processing, authors got frequency dependencies for various biological objects of agriculture. (Conclusions) The processing of an array of experimental data will allow us to determine the functional, statistical and logical dependencies between the output and input values of the presented device.

Possible Directions in the Improvement of Small-Sized Household Drying Plants

The main problem that we have to face in agriculture is processing and storage of agricultural products. One of the most preferred processing methods is drying. The dried product is stored longer, while the requirements for storage conditions are more tolerant. Standard dryers are a sealed chamber where the dried product is located; they work in cycles: loading-drying-unloading. Such characteristics are well suited for small agricultural enterprises. Traditional drying methods, as a rule, involve large energy costs and take a long time. The development of highly efficient drying equipment is possible because of improving the technology and designs of devices that intensify heat and mass transfer, by creating combined dryers and optimal drying schemes, combining the drying process with other processes. (Research purpose) The research purpose is in considering rational methods of physically justified processes of high-intensity drying of agricultural products for the development of effective drying equipment. (Materials and methods) The description of heat and mass transfer processes allows you to choose a rational method; solve the problem of forecasting processes; determine the way to increase the efficiency of drying and equipment. (Results and discussion) The rate of moisture transfer in the material depends on the moving of moisture inside and the surface of the material to the drying agent. The value of the drying speed depends on the temperature, humidity and air speed, the dried air accelerates the drying process. (Conclusions) The magnitude and relative direction of the thermodynamic forces of moisture conductivity and thermal moisture conductivity determines the intensity of material dehydration. For a specific drying method, optimal technological modes of dehydration should be created, ensuring the production of high-quality materials. Closed-cycle devices with recirculation of the drying agent and heat energy recovery reduce the energy consumption for the process.

Influence of Microwave Radiation on the Freezing Rate of Water in a Heat Pump Installation

The article presents the data obtained as a result of an experiment to determine the effect of microwave radiation on the freezing rate of water in a heat pump installation are presented. (Research purpose) The research purpose is in experimentally evaluating the effect of microwave radiation on the speed of the water-ice phase transition to increase the efficiency of the heat pump unit by increasing the rate of water crystallization. (Materials and methods) The main criterion for conducting the experiment was the speed of the water-ice phase transition of ordinary water and water that passed through microwave radiation. The article presents an experimental installation for conducting experiments, consisting of a 90-liter freezer, a Danfoss TLES4F compressor with a cooling capacity of 91 Watts, a programmable Arduino controller with four connected sealed DS18B20 temperature sensors, a water tank made of food- grade plastic. The article presents the scheme of the experimental installation. The water was treated with microwave radiation for 12 seconds, the thickness of the water layer was 4-5 millimeters, and the power of the magnetron used was 750 Watts. (Results and discussion) There was conducted 20 experiments on obtaining thermal energy using the water-ice phase transition. Ten experiments with ordinary filtered water and ten experiments with water subjected to microwave radiation. (Conclusions) Water subjected to uniform microwave radiation cools to 0 degrees Celsius 23 minutes earlier than water that has passed only filtration, and performs a phase transition to a solid state 74 minutes faster. Microwave radiation can be used to increase the efficiency of a heat pump using the energy of the water-ice phase transition by accelerating the production of thermal energy from the heat carrier to the heat supply system.

Research of the Solar Electromagnetic Motor

The article presents the Mendocino solar engine and the solar unipolar engine and their shortcomings. A new solar electromagnetic engine was introduced. (Research purpose) The research purpose is in studying the electrical and mechanical characteristics of a solar electromagnetic motor. (Materials and methods) The LED digital switching DC power supply LW-K3010D; magnetic field detector; digital tachometers RPM, TL-900, DT-2234C; digital LED thermometer 1M-50⁓100; digital voltmeter 0.28 Inch Red; multimeters MAS830L, MAS838L, DT-181, HP-4070L; ammeters M4204; energy meter Dudget KIT MT-4014 were used during the study. The experimental method was used. (Results and discussion) Authors experimentally developed several engine designs. With a rotor diameter of 100 millimeters and a voltage of a high-voltage solar photovoltaic module of 110 volts, the power consumption is 0.44 watts, the rotor rotation speed is 750 rpm. The solar electromagnetic motor with a rotor diameter of 250 millimeters and a total rotor weight of one kilogram consumes 1.9 watts and has 100 rpm at free mode. (Conclusions) The article presents the designs of a solar electromagnetic motor in which there are no losses for eddy currents when the rotor rotates in a constant magnetic field of the stator, and the magnetic field of the rotor currents strengthens the magnetic field of the stator. The advantages of the proposed solar electromagnetic motor are high voltage and low currents in the electric windings, low energy consumption and no losses for eddy currents, for shading solar cells and for friction in sliding contacts. The results allow us to conclude the possibility of further development of solar electric machines using neodymium magnets, ionistors, high- voltage solar modules.

Thermal Mode of Floor Power Plants in the Areas of Keeping Young Piglets

Agricultural enterprises include engineering systems for ensuring the vital activity of animals. The effectiveness of such systems is determined by creating the required conditions in places where animals are kept in interaction with external temperature parameters of the habitat. (Research purpose) The research purpose is in considering the physical model of the heat flows distribution in piglets' recreation areas, developing the structural diagram of the power equipment of local installations to maintain a given thermal mode. (Materials and methods) The state of the issue was studied using theoretical models for describing a comfortable thermal mode for young animals. The physical model of "animal-environment" heat transfer was presented. The article describes the boundaries of the area of heat flow change to create comfortable conditions for keeping piglets of different age groups. (Results and discussion) The contact method of heating piglets is characterized by high technological and energy efficiency. When the young animals are located on a surface heated to the required temperature, the outflow of heat from the animal's body to the floor is significantly reduced; hypothermia of vital organs is prevented. The normal vital activity of the animal is possible within a limited range of the surface temperature in their locations, the temperature factor is the key. Depending on the environmental conditions and the duration of the growing cycle, a certain level of thermal energy should be generated with a variable direction of the heat flow in the "animal-environment" thermodynamic system. (Conclusions) The article describes the necessity of developing fundamentally new technical means with a variable direction of heat flows. The article presents a structural scheme of local power equipment for maintaining a given thermal regime in the area of piglets with a variable heat flow in the "animal-environment" system. The results of the study serve as the basis for the design of operating modes of thermal power equipment, including using Peltier thermodynamic modules.