The article is devoted to modeling heating of fuel oil using a pulsed fluid flow in the SolidWorks Flow Simulation software module. In the future, the use of this technological solution can be considered by a number of industries in the Russian Federation and abroad. The purpose of this article is to describe the results of a computer model of the technological process under study. The computer calculation of the fuel oil heating model using a pulse flow makes it possible to evaluate the efficiency of the process and determine the optimal parameters to achieve maximum efficiency. This will help to reduce the cost of heating fuel oil and increase the efficiency of industrial equipment of enterprises.
Keywords: fuel oil, oil, coolant, shock unit, diaphragm pump, pulse flow, turbulent mode, cavitation, solidworks flow simulation
The article presents a feasibility study of the use of the izoproflex-115A pipeline based on thermal and hydraulic calculations of existing thermal networks in Saransk. When modeling two variants (pipe networks made of steel in polyurethane foam insulation and polymer pipelines "izoproflex-115") of pipelines, the same technique was used. Analysis of the calculation results of the longest section of the heat network showed that ISOPROFLEX pipes, on average, have a three-fold capacity reserve in relation to a steel pipe. The use of modern izoproflex-115A pipeline systems will ensure high-quality and uninterrupted heat supply to consumers, increase energy security and energy efficiency, reduce the accident rate of heat supply systems and improve the financial performance of heat supply organizations.
Keywords: heating networks, pipeline, reserve, capacity, heat supply, consumer, insulation, electronic model, isoproflex-115A, Zulu Thermo
The paper studies the problems of heat transfer intensification in shell-and-tube heat exchangers used in the heat supply of buildings. The solution to this problem is to use the circulation of the coolant flow in a pulsed mode, with different frequency pulsations. Based on experimental studies to determine the efficiency of a shell-and-tube water-to-water heat exchanger, a method has been proposed, in accordance with which it has been proved that the pulsed mode, compared to the stationary one, is the most effective in terms of key indicators, such as the heat transfer coefficient and thermal power.
Keywords: intensification, heat transfer, heat exchanger, coolant, fluctuations, efficiency, thermal power
The article studies the thermal conditions in the heating system of a two-storey building of the laboratory building of the Medical Institute. The analysis was carried out on the basis of data obtained from thermograms of heating devices. The study of thermal conditions in a two-pipe heating system is carried out, the actual and estimated power of each heating device is determined, as well as the temperature inside the premises.
Keywords: Coolant regulation, heating system, thermostat, thermal modes, thermogram, coolant, balancing, heating system
The paper presents a comparative assessment of the methods for generating radiation in the form of a two and three-frequency symmetric packet of discrete frequencies, both traditional on the basis of the Mach-Zehnder modulator operating at various operating points, and the author's on the basis of tandem amplitude-phase modulation. The generated emissions are special cases of an ultra-narrowband packet of discrete frequencies used to construct radio-photonic vector analyzers. Based on the results of computer simulation of the shapers in specialized software, a qualitative and quantitative assessment of the purity of the generated radiation is given, which confirms the results obtained for mathematical models and their adequacy to the described physical processes.
Keywords: modulation of optical radiation, ultra-narrowband packet of discrete frequencies, Mach-Zehnder modulator, tandem amplitude-phase modulation, electroabsorption modulator
The paper presents the concept of constructing microwave photonic vector analyzers of a new type based on an ultra-narrowband packet of discrete frequencies, formulated as a result of a comparative analysis of existing methods for constructing optical vector analyzers.
Keywords: optical vector analyzer, microwave photonics, microwave photonic vector analyzer, modulation of optical radiation, ultra-narrowband package of discrete frequencies
The work is devoted to some questions of prosthetics of human limbs. A prototype of a prosthesis control system based on electromyography is suggested, which is not inferior to existing analogues, but significantly benefits in its cost.
Keywords: bionic prosthesis, electromyography, EMG sensor, amplifier
The article considers the issue of measuring and controlling the parameters of a high-voltage AC circuit using a Bragg grid. A model of a fiber-optic sensor based on the magnetostriction effect, the main component of which is a fiber-Bragg grating, is proposed. The 3D modeling of the magnetostriction process and the design of the block diagram are carried out.
Keywords: optical fiber, magnetostriction, bragg grid, AC, sensor, solenoid, coil, nickel, ferrite, MathCAD, COMSOL
The technologies for producing ultrafine copper powders are examined. The influence of various parameters on the processes of electrocrystallization of particles is studied. Various mechanisms for producing particles in the presence of water-soluble polymers are presented. The ultrafine copper powders obtained using different electrolysis modes. A review of advanced electrochemical methods for producing ultrafine copper powders with the addition of various stabilizers particle growth, further ways of developing the technology of these technologies are highlighted.
Keywords: ultrafine copper powders, electrocrystallization, production methods, particle stabilization, water-soluble polymers, double electric layer, vibrocathode
A method for the intellectualization of measurement procedures has been developed. It is based on the step-by-step optimization procedure, which provides a reduction of the stochastic estimation problem to a number of deterministic problems. The task of the first stage of optimization is the synthesis of an adaptive mathematical model of the measuring process based on the combined principle of maximum, which, unlike the known methods, will ensure the constructiveness of its use in the next stages of optimization. The task of the subsequent stages of optimization is to solve the estimation problem based on the regularization method A.N. Tikhonov. Equations of an iterative measurement procedure are obtained that differ from the state transition vector functions known in structure. It belongs to the category of intelligent measuring procedures, since it makes a targeted choice of the closest to the true value of the assessment of the measured parameter in the conditions of structural uncertainty of the model of the studied object and parametric uncertainty of the observation model.
Keywords: two-stage synthesis, intellectualization, the combined principle of maximum, regularization
The paper describes the implementation of a fiber-optic single-channel vibration sensor built on the basis of two fiber Bragg gratings, a broadband source, a photodetector and a sound card of a computer used as an ADC
Keywords: vibration, fiber optic sensor, fiber Bragg grating, Fourier transform
The complexity and high cost of multiplexing optical fiber sensors is still the main limitation for the widespread introduction of sensory systems, both distributed and quasi-distributed, and point-like. The article proposes a new multiplexing method that takes advantage of both broadband and two-frequency radio-photon multiplexing systems. The simplest broadband radiator is taken from the first, but a complicated and expensive system of spectrometry is not used to determine the central wavelength of fiber Bragg gratings. From the second, a recording system is used at the beat frequency between two components, but an expensive system for generating two- and polyharmonic probing systems is not used. The multiplexing parameter is determined by the frequency of separation between the transparency windows of a fiber Bragg grating, for example, with two phase π-shifts, which differs by a certain value for each of the sensors. The mechanism of modeling of gratings of the specified type is given, in principle the possibility of multiplexing of various number of sensors is shown. When using sensor networks built on the basis of passive optical, the number of multiplexed sensors can reach 256, with all sensors having the same Bragg wave of the wave, and can be combined into tree, bus and other topologies.
Keywords: fiber Bragg grating, phase inhomogeneity, fiber optic sensor, multiplexing, transparency window, frequency difference between transparency windows, beat frequency
The article presents the results of an experimental research on the effect of the pulsating mode a capacitive heat exchanger with an active pipe part on the convective processes heated fluid. Described dignity capacitive heat exchangers. The research was conducted using a thermal imaging surveys. Compares two modes: stationary and pulsating. The method of experimental data processing, based on the analysis of fluid layers. A regression analysis allows to determine the dependence of the relative distribution of the temperature difference between the layers of fluid in the studied mode. The obtained regression equations were presented in the form of an exponential function and harmonic. The effect of pulsing regime on the process of convection in the upper quarter of the heating zone in a capacitive heat exchanger. The study showed the advantage of the capacitive heat exchanger with an active pipe part is often compared with the classical heat exchanger in part the speed of convective processes in the fluid to be heated.
Keywords: capacitive heat exchanger with an active pipe part, pulse heating system, convective process