Журнал “НТС” №3 2023 (48)

PCVEXPO — FROM A BEGINNING TO… A BEGINNING?

Evgeny Vladimirovich Solodchenkov

Abstract. On October 24—26, the 23rd PCVEXPO exhibition “Pumps. Compressors. Fittings. Drives and engines” will be held. In this article I would like to take a retrospective look at the stages of the exhibition’s formation and assess the prospects for its further development in the context of current realities.

Keywords: pump production, centrifugal pumps, PCVEXPO.

STATISTICAL ASSESSMENT OF THE TECHNICAL PERFECTION OF JET ENGINES OF VARIOUS TYPES

Mikhail Yurievich Vovk , Viktor Valentinovich Kulalaev , Viktor Grigorievich Petrienko

Abstract. The article develops a methodology for statistical assessment of the technical excellence of various types of jet engines (JE) to create a block of information base parameters of the most successful world-class engines, selected as prototypes for making effective design and technical decisions in the development of a new generation of jet engines. A universal criterion of technical excellence has been formulated and constructed. It is shown that, based on a systemic statistical analysis of the parameters and adopted design decisions of the group, successful world-class RDs, selected as prototypes based on the presented criterion, allows, when creating a new generation RD at the stage of preliminary design, to make scientific and technical decisions with maximum efficiency and minimum the likelihood of making wrong decisions. An example of testing the application of the criterion when calculating the characteristics of a scramjet engine is presented. In systemic statistical studies of the technical perfection of RDs, the application of the introduced criterion leads to a reduction in the time for creating new generation engines.

Keywords: jet engine, statistical research, analogue, prototype, criterion, characteristics.

DETERMINING PROMISING DIRECTIONS FOR INCREASING THE EFFICIENCY OF THE WORKING CHAMBER OF A DIAPHRAGM-PISTON PUMP

Alexander Andreevich Polikarpov , Maxim Petrovich Feropontov

Abstract. The work shows the research results about problem areas of the pumped medium flow in the working chamber of a diaphragm-piston pump. The necessary dependencies of the pump operating parameters were determined, on the basis of which the nature of the change in the geometry of the membrane and the flow rate over time was revealed. Numerical modeling of the flow in the working chamber was carried out for different moments of time in a stationary setting, and problematic hydraulic zones were found.

Keywords: membrane-piston pump, working chamber, computational model, numerical modeling.

FEATURES OF DETECTING DEFECTS IN ULTRASONIC TESTING

Sergey Vladimirovich Safonov, Maxim Nikolaevich Davydov, Olga Ivanovna Popova, Margarita Ivanovna Popova

Abstract. This article discusses the features of detecting defects of the “pore” type in steel welded joints and defects of the “loose” type in cast body parts. Identification of a “loose” type defect was performed using an A1550 IntroVisor ultrasonic flaw detector-tomograph. Identification of a “pore” type defect was performed by an ultrasonic flaw detector USD-50 IPS. A graph of the dependence of the frontal size of the image on the depth of its occurrence is obtained, which simplifies and speeds up the search for the value of the allowable size for intermediate depths. From the data obtained, using formula (1), it is possible to find out the actual dimensions of defects such as “looseness” occurring in the product. The probability of detecting defects of the “pore” type is possible with the help of tuning samples from fragments of welded joints, with artificial defects imitating a relief reflective surface and localized in the zone of possible occurrence, this will allow a more objective assessment of the detected defect. With the help of such samples, it is possible to narrow the control zone and focus in the subsurface and middle parts of the welded joint, as well as introduce sensitivity corrections taking into account the uneven reflective surface of the discontinuity.

Keywords: non-destructive testing, ultrasonic testing, “loose” type defect, “pore” type defect.

PROBLEMS AND FEATURES OF MATERIAL FLOW MANAGEMENT IN SMALL-SCALE PRODUCTION

Natalya Nikolaevna Golub1 , Sergey Alekseevich Povekvechnykh

Abstract. This article examines the key problems of managing material flows of small-scale production, and also identifies the features of their operational and production management. It is shown that in small-scale production in conditions of partial automation of both management and production processes, the task of forming an effective system of operational production management continues to be acute.

Keywords: production planning, complete-unit system, small-scale production.

SURFACES PREPARATION BY COMBINED PROCESSING TO ENSURE THE QUALITY OF THIN-WALLED SHELL ASSEMBLY

Gennady Alekseevich Sukhochev, Sergey Nikolaevich Podgornov, Vitaly Yuryevich Akulov

Abstract. This work is focused on the development of technology for combined processing of mating surfaces for the quality of thin-walled shells assembly with an ogival profile. The proposed theological modes make it possible to improve the quality and achieve the specified parameters for the assembly of high-tech aerospace products units.

Keywords: combined processing, surface preparation, quality improvement, thin-walled shell, assembly of ogival profile elements.

CURRENT STATE OF TITANIUM ALLOY PIPES PRODUCTION FOR NUCLEAR POWER AND SHIPBUILDING

Pavel Sergeevich Krylov, Lyubov Pavlovna Rtishcheva, Tatyana Aleksandrovna Martynova, Elena Sergeevna Evstigneeva, Valery Petrovich Leonov

Abstract. As a result of the work completed by the NRC “Kurchatov Institute”  — CRISM “Prometheus”, modern technologies for the manufacture of hot-formed and cold-formed pipes from titanium alloys at the plants of the Russian Federation have been developed. To confirm the reliability and cyclic strength of hot-formed pipes, hydraulic cyclic tests of model made of pipes were performed. Tests have shown the high quality and reliability of pipes manufactured using the developed technologies. To improve the strength characteristics, a technology for manufacturing cold-formed pipes with a fine-grained structure has been developed.

Keywords: titanium alloys, hot-deformed pipes, cold-deformed pipes, fine-grained structure.

DEVELOPING A METHOD FOR PROFILING THE IMPELLER OF A CENTRIFUGAL PUMP BASED ON NEURAL NETWORK ALGORITHMS AND HYDRODYNAMIC MODELING

Sergey Georgievich Valyukhov, Alexander Valentinovich Kretinin, Elena Mikhailovna Obolonskaya

Abstract. A technique profiling the flow part of a centrifugal pump based on numerical methods of hydrodynamics and neural network modeling methods has been developed. The generated mathematical models were tested and identified. The distributions of hydrodynamic parameters and the values of integral operating parameters are obtained. The spatial profile of the centrifugal wheel blade was obtained, at which the hydraulic efficiency of the wheel is 93.3 %.

Keywords: centrifugal pump, computational fluid dynamics, neural network algorithms.

INFLUENCE OF THE TRAILING EDGE SHAPE OF THE CENTRIFUGAL PUMP IMPELLER ON THE PUMP EFFICIENCY AND REVERSE CURRENTS IN THE FLOW PART

Andrey Vladimirovich Ivanov, Dmitry Nikolaevich Galdin, Sergey Vladimirovich Yaroslavtsev

Abstract. This article examines how the trailing edge shape of the impeller blade influences on the efficiency of a centrifugal pump and the magnitude of reverse currents. The geometry of the impeller in the blade guide vane is considered. 16 different leading edge geometries were studied. The results showed that, compared with the original option, thinning the edge slightly increases efficiency, while some options significantly reduce it. The change in shape has a significant impact on the amount of reverse flow in the flow part.

Keywords: centrifugal pump, computational fluid dynamics, blade shape.

THE FLOW METER COLLECTOR VERIFICATION METHOD WHEN CONDUCTING A COMPUTATIONAL EXPERIMENT

Danil Alekseevich Chernyshov , Vasily Sergeevich Levin , Konstantin Vladimirovich Kruzhaev , Igor Gennadievich Drozdov4 , Tatyana Aleksandrovna Basharina

Abstract: This paper examines the design of a flow meter manifold for an air flow measurement system with an axial inlet to a gas turbine engine. To ensure reliability and high accuracy of measurements (no more than 0.5 % of the measured value), it is necessary to verify the flow meter manifold, which is an expensive and time-consuming process during its manufacture and pilot testing of engines. As a result of the research, the possibility of determining the calibration characteristics of the flow meter manifold by conducting a numerical experiment was confirmed. The resulting mathematical model makes it possible to determine the values of the flow coefficients and the total pressure field of the flow meter manifold, as well as the dimensionless coefficient of the total pressure field without testing on specialized test benches, which will significantly speed up the manufacturing process of the flow meter manifold and the gas turbine engine as a whole. The error in determining the flow coefficient was 0.07 %, which does not exceed the permissible error of 0.25 % established by regulatory documents.

Keywords: flow meter manifold, verification method, numerical experiment, gas turbine engine.

APPLICATION OF THE LATTICE - BOLTZMANN METHOD AND CELLULAR AUTOMATA FOR MODELING FLUID DYNAMICS IN THE FLOW PART OF A BLADE MACHINE

Alexander Valentinovich Kretinin, Dmitry Valerievich Soldatov

Abstract. Theoretical and algorithmic justification for the use of cellular automata for modeling hydrodynamic processes in the flow part of blade machines is presented. The possibility of using the Lattice-Boltzmann method for modeling simplified microdynamics of fluid media is considered. The use of the developed computer program makes it possible to simulate fluid dynamics in various channels of complex technical systems.

Keywords: fluid dynamics, cellular automata, Lattice – Boltzmann.

MATHEMATICAL MODEL OF THE RATIONAL FORM OF A PLANE INLET SECTION OF THE AIR INTAKE CHANNEL IN ORDER TO ENSURE THE LOWEST INTENSITY OF VORTEX CURRENTS

Alexey Kafisovich Aisin, Andrey Alexandrovich Achekin, Alexander Alexandrovich Preis

Abstract. In the system under consideration, an air intake of a symmetrical shape with an underwing location is considered without taking into account the influence of wind conditions. The maximum horizontal velocity on the surface under the air intake was chosen as a criterion for the intensity of vortex formation. The proposed mathematical model consists of dividing the cross-section of the entrance to the air intake into n elementary parts. The total air flow through the air intake is equal to the sum of the flow through each elementary area. The influence of each i-th elementary part on the intensity of the wall flow is inversely proportional to the square of the height of the location of its geometric center. Thus, the minimum intensity can be achieved by the shape of the air intake inlet section, the geometric center of which is maximally distant from the surface.

Keywords: air intake shape, mathematical model, intensity of vortex formation, maximum horizontal speed.