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In the presented work, the issues of measuring the thrust force of spacecraft thrusters are considered. A program for determining the thrust force based on machine vision has been developed. A mathematical model of the mechanical part of the stand has been compiled. Numerical modeling of the compiled system of equations is carried out. The simulation results are processed using the developed program. The relative error of misalignment is no more than 5 %. Field experiments are carried out and the thrust levels of the ion thruster are measured. A comparative analysis of the experimental results obtained with a mathematical model is shown. Experimental studies have been conducted to determine the thrust of a prototype arcjet thruster using a stand based on machine vision and using a stand based on a displacement sensor. The discrepancy in the results of the thrust force is  5,6 %.

The article presents a quantum mechanical model of an ion thruster. The basic equations describing the shape of the accelerated beam are considered. Detector plates demonstrating the interference pattern in thin films are presented. A mathematical description of the relief of thin films is given using the resulting wave function. The operation of a low-power ion engine is demonstrated. The results of numerical solution of the model with different initial values are shown. Based on the results of calculations, diagrams of the trajectories of charged particles are constructed.

The article examines mechanisms for deepening interaction between universities and enterprises in order to improve the quality of training of specialists and solve scientific and production problems, first of all, considering the problems of organizing production on the basis of a university, in particular, the problems of creating small innovative enterprises in a university environment and the possibility of commercialization are considered scientific and educational activities. The authors consider the features of the activities of small innovative enterprises and emerging risks. They offer mechanisms for building relationships with industrial partners. They pay attention to the rather complex procedure and rules for creating production activities on the basis of a university, analyze the experience of the functioning of small industrial enterprises in Russia, and highlight several problems that in one way or another hinder the widespread organization of production on the basis of universities. The scientific novelty of the article is the attempt to combine into a single system all forms and methods of interaction between the university, school and industrial partner through the creation of a holding company based on basic departments. The main research methods: studying the experience of the country’s leading universities, through the analysis of their charters and the analysis of Internet resources on the functioning of small innovative enterprises — in universities.

In this paper, the applied problems of designing a bridge resonant converter with a high-voltage arc ignition system in the channel of an electric arc motor is solved. The development of a bridge resonant power supply is presented, a review and analysis of power sources of arcjet thruster of various capacities is carried out. The theoretical aspects of calculating the main parameters of the source are considered. The transfer function describing the gain of the resonant circuit of the power supply is given. With the help of the transfer function, gain diagrams are constructed for various values of the Q-factor of the contour. A prototype of a power supply, a starting system and an arcjet thruster is presented. A series of experiments aimed at identifying the operability of the source is carried out. According to the experimental results, the maximum output power of the source wiz 182,4 watts, and the maximum efficiency is 87,5 %. Frequency spectra of the output current of the power supply are obtained. The current-voltage characteristics for the Ar and N2 are constructed. In the course of the study, phenomena related to the chaotic dynamics of the arc in the engine channel are discovered. Chaotic fluctuations are observed at the moment of starting the engine and disappeared after steady-state operation.

A mathematical model of thermodynamic processes occurring in the arcjet thruster device with using argon for arcjet working process carring out. A comparative analysis of the results of experimental data with theoretical data has been carried out. The purpose of the study is to develop a mathematical model of thermodynamic processes in the arcjet thruster device and simulate the interaction of argon with arc discharge plasma. The comparative analysis of the calculated parameters, thanks to the proximity of electron temperature values with the previously experimentally obtained under the static state in the arcjet thruster device, confirms the reliability of the presented mathematical model of plasma processes and the need for its improvement.

When designing natural gas drying equipment, the possibility of implementing an integrated approach to determine the rational technical and economic indicators of the technological devices under consideration is of great importance. This makes it possible to achieve maximum energy efficiency from the operated equipment for each specific field. One of the important tasks to be solved in the development of gas fields is the choice of a method and appropriate technological equipment according to a variety of criteria, including operating costs and the cost of devices, plant performance, metal consumption, replicability of the technology in question, etc. One of the ways to solve such a problem is the application of mathematical methods of system analysis in complex decision-making problems, in particular, the method of analyzing hierarchies.

The article presents the results of a study related to determining the need to replace pumping equipment or impellers of main pumps to increase efficiency while reducing pumping volumes. Calculations are carried out on the example of a technological section of a specific oil pipeline. The paper demonstrates an approach to assessing the economic feasibility of replacing pumping equipment or upgrading it in conditions of changing transportation volumes. The calculation method can be applied to any oil pipelines and product pipelines.

The article presents the results of a study related to the choice of modes and pressure regulation to save electricity. Calculations are carried out on the example of a technological section of a specific oil pipeline. The paper demonstrates an approach to assessing the economic efficiency of each of the flow control options to obtain the required performance. The above arguments and methods of selecting modes can be applied to any oil pipelines and product pipelines.

The article discusses the features of the inertial explosion of metal products and the prevention of its occurrence during its impact introduction of a metal penetrator into the ground of celestial bodies. The possibility of an inertial explosion in metal penetrators is determined when calculating the critical overload of the Gcr that exceeds a certain threshold value for each metal. These values are determined for a number of alloys and high-purity metals widely used in rocket and space technology for Earth and space temperatures. The features of reducing the critical overload threshold of the Gcr for space conditions at cryogenic temperatures and ways to prevent an inertial explosion are discussed

The article describes the possibility of using the «Method of analysis of hierarchies» when choosing the type of separator. These calculation methods are used to determine the vector of priorities and alternatives according to specified criteria, as well as to assess the consistency of expert opinions. The task is set, alternative options and criteria for selecting a separator design are presented. A hierarchical structure is built for various designs of separators. The method of calculation for a variety of indicators that characterize the types of separation equipment is presented. Based on the results presented in accordance with the technical and economic indicators, the optimal design of the separator is determined

In order to increase the efficiency of the absorption dehydration of the integrated gas treatment unit during peak summer operating modes, when the temperature of the dried gas significantly exceeds +25°C, a preliminary dehydration system has been introduced into the processing flow chart. The implemented technical and technological improvements both of the internal elements of the separation equipment and the piping system of the gas dehydration shop made it possible to reduce the carryover of droplet moisture from the separation and absorption equipment, as well as to ensure compliance with the current standards for commercial gas for the key parameter dew point temperature, in compliance with the required technological reserve

Based on the calculated data obtained by using the software complex of modeling of technological processes for preparation of hydrocarbon raw materials of the domestic development «GIBBS», the article confirmed the advantage of triethylene glycol relative to diethylene glycol in terms of reduction of dew point temperature of dried gas in changing thermobaric conditions of operation of technological equipment of the complex gas treatment plant. The design parameters are confirmed by experimental data obtained during operation of the natural gas drying system at the facilities of Gazprom dobycha Noyabrsk LLC, where triethylene glycol is used as an absorbent

To determine the performance characteristics of rubber-cord pipes under the influence of internal overpressure taking into account the relative displacement of the ends (flanges), an unconventional method of approximate analytical solution and the subsequent increase in the accuracy of calculating the stress-strain state of rubber-cord shells with tensile cord casing is used. The fundamental difference between the force created by the rubber cord pipe and the spacer force is taken into consideration. The calculation is compared with the results of experiments on fracture, the calculated value of the excess fracture pressure fits into the confidence interval of the spread of experimental data. Examples of constructing isobar power characteristics of sleeve-type pneumatic shock absorbers (sleeve tensilecompression shock absorbers) are shown and the features of their behavior are analyzed at different values of the operating and design parameters of the rubber cord pipe. The results are intended for engineering calculations and the optimal design of rubber cord pipes used to connect pipelines, or as air shock absorbers to protect technical objects from vibration and shock

The article discusses the results of an experimental study of cooling systems with intensification of inertial forces in a field, obtained on a modernized experimental bench. This stand made it possible to study the efficiency of heating the components of liquid fuel of a hydrocarbon coolant in the field of inertial forces and verify the results obtained in ANSYS.

The procedure of linearization of the previously constructed mathematical model of a rubber-cord shell of rotation with elastically deformable cord threads under symmetric loading with internal excessive pressure and axial force is performed. The characteristic specialty of the linearized mathematical model is analyzed, special attention is paid to the correct choice of the unloaded reference configuration, which takes place not at zero excess pressure, but at excess pressure tending to zero. It is noted that the linearized mathematical model is of the greatest practical interest for analytical calculation and design of rubber-cord branch pipes and pneumatic sleeve-type shock absorbers with optimal performance characteristics

A significant number of the main design parameters of the small upper stage for the group launch of small spacecraft with a propulsion system with a displacement fuel supply system determines the relevance of the random search method. The aim of the work is to create a method of selecting the main design parameters of the small upper stage by random search. The mathematical model based on the dimensional-mass model of the calculated mass determination provides the choice of the optimal mass of the upper stage, taking into account the complex relationships of the studied parameters

The kinetic theory of gases methods has been used to evaluate the erosion DC arcjet tungsten electrodes. Argon is chosen as the process plasma gas. Estimation of the mass flow rate of tungsten due to erosion is performed as a result of determining the gas temperature and the maximum flow rate of arcjet gases

The review of the fundamental scientific works on the mechanics of pneumatic tires is given. A mathematical model is proposed for a rubber-cord shell, taking into account the tensile properties of the cord threads and the elastic resistance of the rubber matrix without limiting the magnitude of the deformations, which differs from the mathematical model of the moment-free theory of mesh shells used in pneumatic tires mechanics. The applied loads are assumed to be static and axisymmetric. Equilibrium equations are compiled in the form that excludes the emergence of a singularity at special points and does not require special techniques and tools for integration. To construct the constitutive relations reflecting the structural heterogeneity of the material and described by smooth functions of spatial coordinates, the principle of virtual displacements is used. The order of solving the equations of the mathematical model is indicated. A critical analysis of the known variants of the theoretical description of the initial geometry of the rubber-cord shell after its manufacture is given. A modified method is proposed, based on the consideration of the process of deformation of the representative element of the workpiece and generally accepted assumptions. The redundancy and inadmissibility of the assumption of the constancy of the pitch between the cords or the assumption of the constancy of the area of the elementary rhombic cell of the workpiece are indicated. The developed mathematical model is designed to design air springs with optimal performance

The article discusses the design of a modernized test bench for the study of cooling systems with intensification of inertial forces in the field. This bench will allow investigation the efficiency of heating the hydrocarbon coolant in the field of inertial forces and verification of the calculation results obtained in ANSYS environment

A large number of basic design parameters of the ammonia propulsion system makes the task of their search by the method of random search urgent. The aim of the research is to create a mathematical model that is adapted to the chosen method. Mathematical model for random design parameters provides the choice of the optimal reduced mass of the propulsion system, taking into account the complex relationships of the investigated parameters, which provides the solution of the given tasks of microsatellite maneuvering

The kinetic theory of gases methods has been used to evaluate plasma arc parameters in the arcjet thruster device. It greatly means the compression process in adiabatic character and gas temperature increasing for excited atoms Boltzmann distribution over the energy levels. Using argon gas for arcjet working process carring out, the way of gas temperature eveluation is offered. The results of the study can be use in the spacecraft arcjet development