Objectives. Development of a model and carrying out numerical calculations for the cooling of thin jets of Hydrogen and Deuterium as applicable to installations on receiving cryogenic monodisperse targets.

Methods. To achieve this purpose, the model of cryogenic jet outflow into the low pressure area was created and using PHOENICS software the temperature change of the surface and the interior of a jet over time for various external parameters is investigated through the numerical method.

Result. The dependences of temperature changes of liquid Hydrogen and Deuterium jets along the jet surface and along the radius depending on the jet diameter, speed, initial jet temperature and pressure in the working chamber of installations for receiving cryogenic monodisperse targets were carried out.

Conclusion. The principal possibility of creating high-speed cryogenic monodisperse targets is shown. According to the calculations, at input of thin liquid jets of Hydrogen or Deuterium with a speed up to 100 m/s into the working chamber with low pressure, jets at a distance of up to 1 mm do not have time to freeze and can be broken into monodisperse drops. Drops are cooled due to evaporation and become granules. The developed model, the program for determination of parameters of steady monodisperse disintegration of liquid cryogenic streams and results of numerical calculations can be used during creation of units for receiving high-speed cryogenic monodisperse targets.

Objectives. Cryogenic surgical instruments have been successfully used to conduct tumor ablation. For a long time, cryoablation procedures in Russia were carried out using cryodestructors cooled with liquid nitrogen, which are able to remove heat from the ablation object with high heat flux density and quickly form a cryoablation zone, while being relatively cheap and easy to operate. However, these instruments turned out to be unsuitable for minimally invasive surgeries; therefore, they are squeezed out of practical medicine and cryosurgical instruments are cooled by throttling argon gas. This led to the purpose of the study - the choice of equipment for the organization of local supercooling of pathological tissue.

Method. To solve the problem of optimizing the cryogenic pipeline, a method was chosen for finding the Pareto-optimal solution. To solve this problem, it is sufficient to increase the pressure in the fluid flow directed to the NCS using a liquid micropump. In the role of quality criteria in this task, we selected: hydraulic loss power and heat loss power.

Result. The following results were obtained: the minimum pressure in the vessel, which ensures the movement of the fluid in a single-phase state, according to the magi-line of 1 m length is 0.75 MPa; With this pressure, through a line with a diameter of 1 mm, the flow rate is maintained up to 6 kg / h; heat dissipation ability of the instrument reaches 608 watts. The thermal load on the cooling system of the heatdissipating device of the device for CA is unsteady and is formed due to the heat reserve accumulated in the patient's tissues.

Conclusion. The use of liquid nitrogen in the undersized cryosurgical equipment makes it possible to overcome the noted drawbacks of liquid cryodestructors.

Objectives. The purpose of the article is to examine the design of the thermoelectric system (TPP) for the extraction of foreign objects from the human body by the method of freezing, as well as the simulation of heat transfer processes in it.

Method. A design and a physical model of the system for the extraction of foreign objects from the human body are proposed, in which the source of cold is a thermoelectric module (TEM) placed on a special mechanical device made in the form of a probe, which also provides removal of heat from the hot junctions of the module. A mathematical model of thermal power plants was developed, implemented on the basis of solving the problem of ice layer growth using the method of solving the non-stationary Fourier differential equation, presented in partial derivatives by reducing it to an equation with full derivatives based on the use of an extended version of the Lame-Clapeyron substitution, and power series, which describes the temperature distribution in the frozen ice layer and satisfies the boundary conditions of the problem.

Result. Data were obtained on the change in temperature of the extracted object and the thickness of the ice layer over time at various values of the cooling capacity of TEM. It is established that the duration of the formation of an ice layer between the object to be extracted and the cold surface of the TEM, which is the executive element of the system, is within narrow limits that meet medical standards, while the speed of the ice growth process depends on its thickness (increasing the cooling capacity of the TEM from 1000 to 3000 W / m2 reduces the duration of the formation of an ice layer, 2 mm thick, by almost 40 s, while the temperature of the extracted object decreases from 269 K to 252 K). It is indicated that the selection of geometric parameters of TEM and its power supply should focus on the limitations on the operation of the device, as well as medical norms and standards in order to avoid the process of frostbite of the adjacent tissues.

Conclusion. A method is proposed for increasing the efficiency of the system, according to which the preliminary cooling of the TPP by an external source of cold is used, as well as the use of forced TEM operation modes.

Objectives. The aim of the study is to develop a computational model of the system of thermal stabilization of elements of electronic equipment (REA), based on the joint use of working substances with a stable melting point and the liquid method of heat sink, the study of the thermophysical processes occurring during its operation.

Method. A computational model of the REA thermostabilization system based on the use of working substances with a stable melting point has been created. The model includes a description of the heat exchange processes during laminar fluid motion in a heat exchanger, determining the duration of stable operation of the REA elements, depending on the flow rate and cooling capacity of a thermoelectric battery (TEB).

Result. The graphs of dependences reflecting the main characteristics of the developed system were obtained, in particular, the dependence of the change in the duration of maintaining the stable temperature of the REA element on its power, the temperature of the cold junctions of the thermopile, scattering at different maximum flow rates of the heat exchanger.

Conclusions. The results of the calculations determine that the duration of complete penetration of the working substance, corresponding to the duration of stable operation of CEA elements, can be within the required limits only if certain very specific conditions are met: using a sufficient amount of the working substance in the heat stabilizing system, corresponding to the temperature and flow rate of the liquid in the heat exchanger. These parameters of the thermal stabilization system must be selected based on the amount of heat emitted per unit of time by the REA element, the duration of its operation, and the characteristics of the thermopile used to cool the fluid.

Objectives. Mathematical modeling of heat transfer in flat channels with turbulators symmetrically located on both its sides, depending on the cross section of the turbulators.

Methods. The calculation was carried out on the basis of a theoretical method based on solving the Reynolds equations factorized by the finite-volume finite-volume method, closed using the Menter shear stress transfer model, and the energy equation on multi-scale intersecting structured grids (FCOM), which was successfully tested in [23].

Results. The article results of calculating the intensified heat exchange in flat channels with double turbulators of different cross sections (square, rectangular, semicircular, triangular) depending on the determining parameters were quite satisfactorily consistent with the existing experimental material, but having an indisputable advantage over the latter, since the assumptions made in their derivation cover a much wider range of defining parameters than the limitations found in the experiments (Pr=0.7÷100, Re=103÷106, h/dE =0.005÷0.2, t/h=1÷200).

Conclusion. According to the results of calculations on the basis of the developed model, it is possible to optimize heat transfer intensification in flat channels with double turbulators of different cross sections, as well as control the heat transfer intensification process. As shown by the calculated data, with the intensification of heat transfer in the flat channels, symmetrical protrusions of square, rectangular and triangular cross sections, i.e. relatively sharp outlines, in the vortices up to the protrusions and behind them the production of turbulence is comparable to energy dissipation, which leads to increased hydraulic losses; for flat channels with protrusions of a semicircular cross section, i.e. relatively smooth outlines, the energy dissipation is much smaller, therefore, the hydraulic resistance in such channels is less. A detailed analysis of the structure of the vortex zones (main, angular, secondary, etc.) between periodic surface flow turbulators of square, semicircular, triangular and rectangular cross sections depending on the geometric and regime parameters of the coolant flow was carried out, the effect of the above vortex zones heat transfer and hydraulic resistance of the channel; additionally confirmed the optimality of application to abrutized turbulators, where hydraulic losses are much smaller than for sharp turbulators, which is directly or indirectly verified by existing experimental material [1—6].

Objectives. Ways to prevent the onset of rollover in the liquefied natural gas storage.

Method. The article deals with modern methods of mathematical modeling and software when solving problems in a nonlinear formulation. A regulatory analysis of existing methods of LNG transportation has been carried out.

Result. Using the mathematical program ANSYS, the rollover process in the liquefied natural gas storage was modeled. In the ANSYS software package, 3d modeling of the process of heat and mass transfer of the stratified liquid in the liquefied natural gas storage was performed. When simulating a rollover phenomenon, the time to its occurrence was 30 minutes, which differs from the experimental value by 1.7%. Based on the results of the calculations, it can be determined that the time to the onset of rollover depends on the concentration of the component layers, on the filling and geometry of the reservoir. These factors lead to an increase in evaporation of liquefied natural gas of 0.04%.

Conclusion. The method of numerical experiment allows to determine the distribution of pressure, temperature, density, concentration in the object under study, without resorting to real experiments. The use of the ANSYS software package of computational fluid dynamics in the process of heat and mass transfer of the stratified liquid in the liquefied natural gas storage is necessary when calculating the increased accuracy.

Objectives. The article considers the problem of accuracy in determining the generalized coordinates of the lever mechanisms of the copy-type setting devices with the condition of excessive mobility. The purpose of the article is to determine the analytical dependence of the generalized coordinates of the mechanism of the copy-type setting device with excess mobility.

Method. The article describes the principle of forming generic coordinates of a copy-type setting device for controlling a three-link anthropomorphic manipulator with 7 degrees of mobility, which allows determining the position of any desired points of a copy-type device for controlling a three-link anthropomorphic manipulator with 7 degrees of mobility by solving the inverse kinematics problem.

Result. Matrices for finding the position of the nodes of the manipulator in space are constructed. Matrices of rotation transformations around generatrix axes and the corresponding formulas for finding the coordinates of the end node are given. The formulas for the transition to the local coordinate system of the corresponding links and the formation of the absolute values of the coordinates are described.

Conclusion. A complex relationship has been revealed that allows one to calculate the absolute values of the coordinates of the wrist joint at known angles between the links and the angles of rotation of the joints. The presented method of determining the coordinates of the system allows to simplify the calculated part and increase the accuracy of determining the end points, which entails a comprehensive increase in the performance of the system “master device - robot”.

Objectives. At present, conducting a computational experiment on a system for protecting information from unauthorized access operated in an automated system is a time consuming process. The greatest difficulty in this area of research is the determination of probabilistic-temporal characteristics and the formation of reports during the operation of the information protection system. In order to analyze, obtain and study the probabilistic-time characteristics of this system, it is necessary to develop a mathematical model of its operation using an imitational modeling tool.

Method. One of the methods for solving this problem is a computational experiment, which is based on the construction of a simulation model. The CPN Tools environment was chosen as a software simulation product, the main advantages of which are: a high level of visualization, the ability to generate various reports on the system operation, fast modifiability of models for solving a different class of problems, as well as integration with other software means for the formation of graphical dependencies.

Result. A simulation model of the system for protecting information from unauthorized access in the “CPN Tools” software environment was developed. protected performance.

Conclusion. The presented im-model model of protecting information from unauthorized access in the software environment “CPN Tools” can be used as a tool in assessing the security of special bodies for the attestation of informatization objects and structural divisions of authorized departments. It can also be used in the design of such systems in order to prevent logical errors, determine their temporal characteristics and compare with the existing ones in accordance with the technical specifications for the system being developed to protect information from unauthorized access.

Objectives. The aim of the study is to select methods and means for the effective modernization of the security system existing in the enterprise.

Method. It is proposed to improve the access control mode using the access control system based on ARDUINO microcontrollers. To highlight the functions of the system and the requirements for it were built UML-diagrams. On the basis of these diagrams, the balls have developed a schematic electrical diagram of the hardware of the system with an indication of all its elements. At the next stage, an algorithm was proposed for the operation of the hardware of the access control system. The implementation of a part of the algorithm for information exchange between the device and the information system is shown in the form of a sketch using the example of packet transmission over an Ethernet network using the TCP protocol. An intuitive interface has been developed for interaction between the access control system and the end user. The necessary information is stored in a database created in a Microsoft SQL Server environment.

Result. The developed system was tested at the enterprise by means of sketches and a multimeter. Test results allow us to conclude that the system is ready for implementation. Conclusion. The article describes one of the methods for upgrading the existing access control system through a more user-friendly interface and the addition of entry/exit functions.

Acknowledgments. The work was commissioned by the company LLC «Kalinin Baranchinsky Electromechanical Plant».

Objectives. The relevance of this article lies in the fact that the problem of increasing the reliability of subsystems of aviation and rocket and space technology in case of sudden independent refusals determines one of the important areas of scientific research. The work is aimed at identifying and analyzing specific features that must be considered when researching and developing passively redundant subsystems, taking into account tolerances in case of sudden independent failures.

Method. During the study, calculations were carried out using the methods of probability, search. The necessity of taking into account assigned and implemented tolerances, multiple and non-multiple reservation, discrete scales of realizable tolerances with different levels of significance, critical probabilities, determining the probability ranges of elements, where redundancy is profitable and unprofitable, is shown.

Result. The possibility of implementing any tolerance for different values of a number of increasing individual multiplicities is revealed, which allows for a given tolerance to pose the task of finding the optimal multiplicity and its corresponding optimal backup structure in the interests of ensuring maximum reliability of the redundant subsystems. Analysis of the presented dependencies for the implemented tolerances of the first and second levels shows that for each tolerance level there are equilibrium values ???????????? at which the critical values of p_kr practically do not change depending on the multiplicities ????????.

Conclusion. A different nature of the change in the critical probabilities ???????????? was found depending on the multiplicities for different values of the tolerances to be realized. So, with tolerances of the first level, larger than 25%, with increasing multiplicity, p_kr increases and smaller than 25% decreases with increasing multiplicity. The similar nature of the change in the p_kr values has a 28.6% tolerance for the implemented second-level tolerances.

Objectives. The aim of the study is to develop information technology design systems for monitoring load-bearing structures of buildings and structures of a higher category of responsibility based on the initial data on the construction object and the results of engineering surveys.

Method. The article discusses the approach to the formalization of the description of the procedure for developing projects for monitoring buildings and structures, based on the design features of the SMC building structures, the engineering experience of designing these systems.

Result. The article presents the conceptual foundations of the developed information technology, the algorithm for determining the monitoring mode based on information about the construction object, the algorithm for the macro to determine the most loaded nodes and elements in the complex finite element modeling. Recommendations are given for determining the control parameters, the composition of the measuring equipment.

Conclusion. The conceptual foundations of information technology developed in the course of the research allow for the further development of algorithms and programs for the automated analysis of information about the object and the construction site in order to obtain the automatic mode of the results necessary for developing monitoring systems for buildings and structures of a higher category of responsibility.

Objectives. Solving the main tasks of designing construction objects in accordance with environmental standards is impossible without computer-aided design and database management systems. The article discusses a part of the software package that will automate the process of ensuring compliance of the object with the standards of "green" construction.

Method. The basis of the project development is the criteria of the system of voluntary environmental certification of real estate objects, approved by the order of the Ministry of Natural Resources of Russia, as well as the criteria of LEED standards. For data analysis, the software complex MapInfo was used.

Result. The structure of the software product has been developed, which will answer the main questions arising in the design of any building, taking into account the standards of green building. For each category the underlying factors (input data) are the corresponding data for each criterion.

Conclusion. The developed software package will provide an opportunity to minimize the impact of a construction object on the environment and increase the energy efficiency of the object under construction. Also, improve the quality of organizational and technological decisions of the construction process, reduce the impact of the construction project on the environment and effectively use resources. Full implementation of the algorithm will make it possible to reduce the time and cost of designing buildings and structures, increase the accuracy of drawing details and structural elements, improve the quality and technical and economic level of the design results, and minimize the costs of manual modeling and testing.

Objectives. The aim of the study is to develop a set of interconnected information blocks for the formation, subsequent processing and application of data in the preparation of reporting and functional documents.

Method. The choice of regularly used templates as a basis for the development of information blocks. Based on the structure and forms of the selected templates, software modules for information block interfaces have been developed.

Result. Based on the results of identifying and analyzing problematic issues in the activities of the operational duty shift for the automation and intellectualization of the activities of specialists, the idea of developing and using universal information blocks as part of a database management system for automated workplaces was proposed. Interfaces of information blocks are included in the composition of each workstation and provide for the processes of: entering, changing, searching and filtering data; Previewing, printing and saving documents. In the development of algorithms, original software solutions were applied: combining data prepared by several specialists, generating document details, transferring information between different workstations, monitoring the availability of documents, accessing the necessary reference information.

Conclusion. The introduction of the developed information blocks: “Schedule of SLM duty”, “Requisites”, “Journal of Carriage of Duty”, “Control”, “Reference book” into the complex of automated workplaces of operational duty shift in the Crisis Management Center allows you to refuse as a result of automation from manual filling of text templates and, as a result, reduce labor intensity, increase resource and improve the quality of preparation of operational reporting documents in the event of accidents, emergencies, fires and functions national documents in the mode of daily activities in accordance with the regulatory, job and functional duties of specialists.

Objectives. The paper discusses the feasibility of using the technogenic raw materials of the coal series in the production of highly efficient wall ceramics. The interest in the man-made raw materials of the coal series (sludge, screenings and cake) as the raw materials used in the manufacture of ceramic products has now greatly increased. The reason for this was the reduction of the base of high-quality clay raw materials, the appreciation of its use in the production of wall ceramics, a large amount of accumulated reserves of various rocks of coal-based man-made raw materials.

Method. The research used the following composition of the raw mix: 70% of technogenic raw materials of the coal series (screenings) and 30% of the clay raw materials. The determination of the physicomechanical properties of the samples was carried out according to GOST 530-2012. Coal dumps are fine- grained products, the solid part of which contains a significant amount of coal.

Result. The technological parameters of obtaining wall ceramic products based on coal slimes are determined. Studied the main physico-technical characteristics of the materials obtained. Phase transformations occurring during the burning and patterns of the formation of the structure of the shard were studied. The feasibility of the production of highly efficient ceramic products with low thermal conductivity and density based on technogenic raw materials of the coal series using the technology of compression molding is shown.

Conclusion. The results of theoretical studies are confirmed by practical data, which consist in the fact that in raw mixtures containing technogenic raw materials of coal series, a sharp increase in strength, taking into account the complete burning of carbon, occurs at temperatures of 1000-1060 ° C. The changes introduced during the production of products using this method will help achieve a significant energy saving of gas and optimization of the firing mode.

Objectives. This article discusses options for additional restraints for support structures made from polymer dowels. The issue of increasing the stability of polymer sheet piles plays a key role in the design and construction of facilities using this type of material. The article compares two variants of the restraining devices and compares them with the non-reinforced version using the example of a notch of the same depth.

Methods. The calculations are carried out by the Coulomb- Mohr methods implemented in the GEO5 software package module “Pit Fencing - Analysis.

Result. The obtained calculations showed the possibility of using both types of restraints in retaining structures made of polymer dowels. Conclusion. Calculations have shown the effectiveness of both methods in their use as additional restraints for supporting structures using PVC dowels.The variant with the installation of the support pipe allows to slightly reduce the deformation of the sheet pile structure, but it does not have the ability to adjust the vertical position of the wall, which is present in the variant with the anchor system by welding the threaded rods to the ends of the metal braces or using talreeps.

Objectives. The article presents the conclusion of the resolving equation for calculating the stability of the flat form of deformation of prismatic beams, taking into account the rheological properties of the material.

Method. The problem is reduced to a second-order differential equation for the twist angle, which is solved numerically by the finite difference method in combination with the Euler method.

Result. The obtained differential equation allows one to take into account the presence of initial imperfections in the form of the initial deflection of the beam, the initial angle of twist, and also the eccentricity of the applied load. The solution of the test problem for a cantilever polymer beam under the action of a concentrated force is presented. The non-linear Maxwell-Gurevich equation is used as the creep law. The value of the long-term critical load is introduced and it is shown that with a load less than the long-term critical creep is limited. It has been established that, as with the squeezed rods, with a load less than the long-term critical, the growth rate of the displacements with time decays. When F = F_dl, the displacements grow at a constant speed, and when F> F_dl, the growth rate of displacements increases with time. The results obtained confirm the validity of the chosen method.

Conclusion. A universal resolving equation is obtained for calculating the stability of a flat shape of bending of rectangular beams, suitable for arbitrary creep laws.

Objectives. The current topical issues of energy and environmental safety of construction sites and the air-conditioning systems that serve them are identified and analyzed.

Method. Using thermal methods and means of controlling heat and power parameters in transitional conditions of energy supply and removal in the system “energy source - energy receiver”, the possibility of identifying its power and flow characteristics that determine and form the processes and modes reflecting the basic quantitative and qualitative levels of current energy transformations.

Result. Options have been proposed to solve this problem through the integrated monitoring of some energy-ecological characteristics of the building structures of buildings and structures at the laboratory-experimental research stand “energy source - energy receiver”. The algorithm for identification of thermodynamic forces, flows, properties, changes and reproduction of entropy in the system “energy source - energy receiver”, a functional model and hierarchical representation of a three-level open thermodynamic system “energy source - energy receiver” are presented, some calculated results -experimental determination of the eco-energy characteristics of a fragment of the building envelope by the example of a brick wall.

Conclusion. It has been suggested and proved that the experience of joint use of the laws of nonequilibrium and phenomenological thermodynamics for research and modeling of nonequilibrium thermodynamic processes occurring in systems of various kinds, allows you to control their ecological state and increases the accuracy of forecasting costs and rational use of energy resources.

Objectives. Foamglass and expanded clay are absolutely fireproof, reliable and environmentally friendly heat insulators. But in the cost of their production, energy costs reach 40 ... 60%.

Method. A part of the thermal energy required for the production of building materials was proposed to be developed by a wind power station (WPP).

Result. A heating plant with a Darya turbine capable of operating in severe climatic conditions has been developed. The bearing part of the wind power installation consists of three simple masts, working mainly in compression. The masts are symmetrically placed relative to the center of the wind farm. The design feature is that the vertical shaft with the turbine is suspended at the top of the swivel at the point where the three almost horizontal cables meet. The free ends of the ropes pass through the blocks on the tops of the masts and are secured with anchors at ground level. Therefore, the shaft works mainly in tension and torsion and is well opposed to transverse vibrations. A simple generator without equipment for voltage and frequency regulation operates at WPPs, as for electric heaters of furnaces to which the generator current is supplied, power conditioning is not required. With a decrease in wind speed and a drop in HPP power, the automation supplies more fuel to the burners to maintain the temperature according to the regulations.

Conclusion. Thus, the WPP capacity fills a part of the required heat output of the furnaces, and the missing part of the heat output is compensated by burning gas or fuel oil. If the WPP is located near the enterprise, then electricity is supplied to the consumer without transformers. It is cheaper to lay cables of a larger section than to complete a wind farm with two power transformers.