SPECTRAL DIAGNOSTICS OF THE HYDROCARBON FUEL COMBUSTION PROCESS

It is proposed to use the methods of applied optical spectroscopy to solve the problem of control and diagnostics of gaseous hydrocarbon fuel combustion in this work. The results of an experimental study of spectroscopic informative parameters characterizing the propane combustion process are presented for three modes: combustion of pure propane without air supply, stoichiometric combustion and combustion with a change in the amount of supplied air relative to stoichiometric combustion. As a result of the experiment, it was found that the most intense bands in the emission spectrum of the flame arising from the combustion of propane correspond to the spectral bands of radicals of combustion products: OH, CH, and C2. While the intensities of various systems of bands in the flame spectrum depend significantly on the composition of the combustible mixture.

MONITORING AND CLASSIFYING THE STATE OF HARD DISKS USING RECURRENT NEURAL NETWORKS

The article considers an approach to solving the problem of monitoring and classifying the states of hard disks, which is solved on a regular basis, within the framework of the concept of non-destructive testing. It is proposed to solve this problem by developing a classification model using machine learning algorithms, in particular, using recurrent neural networks with Simple RNN, LSTM and GRU architectures. To develop a classification model, a data set based on the values of SMART sensors installed on hard disks it used. It represents a group of multidimensional time series. At the same time, the structure of the classification model contains two layers of a neural network with one of the recurrent architectures, as well as a Dropout layer and a Dense layer. The results of experimental studies confirming the advantages of LSTM and GRU architectures as part of hard disk state classification models are presented.

COMBINED SIGNAL PROCESSING METHOD FOR DIAGNOSIS AND MONITORING OF THE INDUCTION MOTORS OPTIMIZED FOR EMBEDDED SYSTEMS

Induction Motors (IM) play a key role in modern industry, so the condition monitoring systems are becoming increasingly relevant. Commercial monitoring systems are usually based on the measurement of IM’s vibrations and the further processing of the measured vibration signals. For those purposes the embedded systems (such as microcontrollers and inexpensive processors) are used. Embedded systems have limited resources, so data processing algorithms should have low computational complexity and require little memory. In this paper, the wellknown methods of processing vibration signals for fault diagnosis of the IM are considered and their main advantages and disadvantages for the implementation in embedded systems are highlighted. The previously proposed method based on a combination of the fast Fourier transform and the statistics of the fractional moments is optimized for vibration signal processing and implementation in embedded systems. The efficiency of diagnosis of such faults as eccentricity and a broke rotor bar, using the proposed method, is verified on the radial vertical vibrations measurements of the real motors under different constant load levels: no load, 50 % of the rated load, 75% of the rated load. The results show that this approach allows accurately diagnose the considered faults independently from the load level.

ON ESTIMATION OF THE INFLUENCE OF THE HUMAN FACTOR ON DETECTION OF DEFECTS IN ULTRASONIC FLAW DETECTION AND DEFECTOMETRY

Based on the analysis of the results of ultrasonic testing, a quantitative assessment of the influence of the human factor on the PoD curves built for independent inspectors, several (different) flaw detection techniques was obtained. It is shown that the average value of the change in the probability of detecting flaws, which determines the value of the correction coefficient equal to 0.015 for flaws with a height of 4 to 12 mm (for the defectometry technique) and 0.18 for flaws with a height of 5 to 12 mm (for flaw detection techniques). For flaws less, than 4 mm in height, the average value of the change in the probability of detecting flaws for individual inspectors depends significantly on the height of the flaw. A significant difference in the average value of the change in the probability of detecting flaws and the standard deviation during inspection by flaw detection and defectometry techniques is associated with the difference in the amount of information provided by the inspection techniques and the individual characteristics of the inspectors.

PRINCIPLES FOR DEVELOPMENT OF PROGRAM INTERFACES IN INDUSTRIAL INFORMATION, MEASURING, AND CONTROLLING SYSTEMS

Industrial information, measuring, and controlling systems have a program module designed to convert measurement results into data for display and control signals. A program module interconnected to other modules by program interfaces. In this case, data transformations are necessary when they are sent between modules. Object-oriented design patterns can be used when programming data transformations. When converting measurement results to objects, the Adapter design pattern can be applied. Programming the Command pattern is intended for converting objects into control signals. Data processing should be separated from their representation, storage and transmission. Functions between modules can be divided using the Model–View–Controller pattern. The use of design patterns reduces the development time and subsequent modification of software for both information, measuring, and control systems, as well as systems in other subjects of science and economics.

ACTIVE CONTROL OF THE TOPOLOGICAL PARAMETERS OF ISLAND CATALYSTS WHEN SOLID OXIDE ELECTROLYTES OF FUEL CELLS ARE DEPOSITED ON THE SURFACE

The method of active technological control of topological parameters of synthesized island catalysts on solid oxide fuel cell electrolytes is considered. The proposed method makes it possible to obtain a catalyst with a maximum active area and high adhesion to a solid oxide electrolyte, which contributes to an increase in the power of the fuel cell and an increase in the operational life. The models of two stages of formation of island films under vacuum and magnetron sputtering presented in this paper were used as a theoretical basis for the creation of a method for active technological control and control of the synthesis of island catalyst in solid oxide fuel cells. Experimental testing of the developed method has shown its efficiency and effectiveness in the creation of solid oxide fuel cells.

SOME ASPECTS OF PRACTICAL BALANCING RIGID ROTORS IN OWN SUPPORTS

The balancing of rotors of fans, pumps, smoke exhausters, blowers (with a capacity of 50...500 kW, with a rotational speed of 950...3000 rpm) in their own supports is carried out most often at industrial enterprises. The effectiveness of this operation is ensured by the implementation of a number of rules, confirmed by practical experience. Some stages of balancing of rotors are considered in the work. A preliminary examination of the mechanism provides an accurate diagnosis and an informed decision for balancing. Correct determination of the angle of installation of the test cargo at various places of installation of the vibration and photo sensor allows reducing the level of vibration and additional loads on the elements of the mechanism during the test run. Controlling the values of the dynamic coefficient of influence during the balancing process allows you to control the change in the stiffness of the base, loosening of threaded connections, which are often the cause of unsuccessful balancing. The above provisions are confirmed by the results of research and practical application.

INVESTIGATION OF TRANSVERSE CRACKS IN ANNULAR WELDED JOINTS OF MAIN GAS PIPELINES LINEAR PART

Statistics of accidents and incidents on main gas pipelines in recent years indicate that almost half of the technogenic events occur due to depressurization in the area of annular welded joints, mainly joints containing defects made during construction and installation work during the construction of gas pipelines. The assessment of the degree of danger and the timing of external inspection and repair or replacement of defective annular welded joints largely depends on the quality of non-destructive testing, the correct identification of the types of defects and the objective determination of their geometric dimensions. To increase the reliability of the assessment of the degree of danger of the detected defects, it is necessary to use additional control methods, in particular, destructive ones. The paper presents the results of surveys and tests of metal fragments of annular welded joints of main gas pipelines containing transverse cracks of annular welded joints in order to determine the causes of the formation of these defects and to assess the degree of danger of the detected transverse cracks of the installation welds of main gas pipelines.

ON THE INFLUENCE OF THE SIZE OF FLAKE GRAPHITE INCLUSIONS AND ITS VOLUME CONTENT ON THE ACOUSTIC PARAMETERS OF CAST IRON AND THE CHARACTERISTICS OF ULTRASONIC LONGITUDINAL WAVE SIGNALS

Algorithms have been presented for calculating the velocity (in the approximation of a fine-layered model) and the attenuation coefficient of a longitudinal ultrasonic wave in cast iron, depending on the average size of graphite elements and its volume content, the calculation results for which are qualitatively confirmed experimentally. The calculation was performed using a fine-layered model of the structure, the graphite inclusions were described in the form of plane-parallel layers placed in an isotropic elastic medium (metal base). Computer simulation of acoustic paths for a mediumcast iron with flake graphite for standard direct converters is carried out in order to study the influence of such a medium on the characteristics of transmitted and received signals during ultrasonic testing. In the course of the research, a previously developed model was used to calculate the attenuation coefficient of longitudinal waves in cast iron with flake graphite due to their Rayleigh and phase scattering on graphite inclusions. Computer simulation of the acoustic characteristics of the signals of a direct linear probe with a phased array in cast iron with flake graphite was carried out, during which the shape of the acoustic pulses of the longitudinal wave was calculated, depending on the distance traveled by the wave and the value of the attenuation coefficient for various models of cast iron. The main modeled characteristics of the transducer include the directivity characteristic and the change in the signal amplitude along the acoustic axis. It is shown that for cast iron with flake graphite, there are cases when the directivity of the probe with a phased array transmitted into the cast iron is practically absent.

QUESTIONS ON OPTIMUM DEVELOPMENT OF COMPLEX FOR MULTI-POINT CONTROL AND EVALUATION OF CONTAMINATION OF WATER BASINS POLLUTED BY WASTE WATER OF MINING AND PROCESSING PLANTS

The paper is devoted to questions on optimum development of complex for control and evaluation of contamination of water basins used for collection of industrial waste water. The purpose of the paper is development of scientific-methodical basics for development of measuring system for control and evaluation of contamination of natural water basins with heavy metals using method of attenuation of irradiation of dissolved organic matters excited by external irradiation. The task on optimization of operational regime of measuring complex for control and evaluation of contamination of natural water basins by waste water of large scale point type polluter of environment with heavy metals. The known model of Shtern-Volmer is used as a basis which assumes non-linear relationship between formed complex and fluorescent irradiations attenuation degree. It is noted that potential possibilities of Shtern-Volmers model are used not fully till now. So that in known researches the water objects polluted by several same sources are mainly researched. It is shown that Shtern-Volmer model is also applicable for analysis and estimation of pollution of water basins by single strong polluter that is mining and processing plants. For analysis the suggested special parameter, inversely proportional to concentration of heavy metals in water is used. Integration of this parameter on all possible values of heavy metals concentration and imposition of special limitation condition on the searched for function of dependence of attenuated part of fluorescent irradiation on maximum concentration of heavy metals make it possible to formulate and solve the task on searching of optimum type of this function providing for the optimum regime of operation of the complex.