Научная электронная библиотека ULRICH'S Periodicals Directory

Сибирский государственный университет
науки и технологий имени академика М.Ф. Решетнева

Сибирский аэрокосмический журнал
ISSN 2712-8970 (Print) ISSN 2782-5760 (on-line)

Сведения об образовательной организации

UDK УДК 629.7.036.54 Doi: 10.31772/2587-6066-2018-19-4-644-650
IMPROVEMENT OF THE METHOD OF DETERMINING CAVITATION CHARACTERISTICS OF THE CENTRIFUGAL PUMPS
V. P. Nazarov, L. P. Nazarova, D. S. Shvetsova, D. A. Savchin
Reshetnev Siberian State University of Science and Technology, 31, Krasnoyarsky Rabochy Av., Krasnoyarsk, 660037, Russian Federation
Cavitation is a process of formation of vapor bubbles within a liquid at low pressure regions. There are strain tensions at low-pressure region, which lead to a gap, producing cavitational cavities. These cavities contain vapor bubbles. When cavities come to a high pressure region, they collapse, leading to a local water hammer which is able to erode the surface of a centrifugal pump. The occurring and the evolution of cavitation in liquids bound to the existence of so called cavitational cores. A physically pure liquid can resist to a strain tension efficiently, however industrial liquids always have cavitational cores. The cavitational cores are undissolved gas inclusions. The acceleration of evolution of cavitation depends on free and dissolved gases and thermodynamic properties of liquid as well. Cavitation brings three negative factors to the performance of a centrifugal pump: performance failure – an abrupt decreasing of main parameters; erosion corrosion; low-frequency pulsations that cause the unstable work. Every centrifugal pump goes through cavitational tests for the determination of the cavitation performance. However, the contemporary test methods do not have the required accuracy; moreover, the duration of a test is bigger than the work time of a pump in a rocket engine. The paper has the suggestion of the accelerated method of cavitational tests. To get the results, the new method works without maintaining of the mass flow rate, but with increased pressure-change speed on the pump entrance. For the decreasing of the error, the new method includes automatic measuring system. The authors have determined that the accelerated method with automatic measuring system does not influence the accuracy, but in the same time makes the test process shorter in time and easier to accomplish.
Keywords: cavitation, centrifugal pump, base characteristics, cavitational tests, accelerated method of cavitational tests.
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Nazarov Vladimir Pavlovich – Cand. Sc., professor, head of Department of Aircraft Engines, Reshetnev Siberian

State University of Science and Technology. E-mail: nazarov@sibsau.ru.

Nazarova Larisa Petrovna – Docent of Department of Technical Mechanics, Reshetnev Siberian State University

of Science and Technology. E-mail: nazarova@sibsau.ru.

Shvetsova Darya Sergeevna – student, Reshetnev Siberian State University of Science and Technology. E-mail:

darya.shvetsova@yandex.ru.

Savchin Dmitriy Aleksandrovich – student, Reshetnev Siberian State University of Science and Technology.

E-mail: savchin.dim@yandex.ru.


  IMPROVEMENT OF THE METHOD OF DETERMINING CAVITATION CHARACTERISTICS OF THE CENTRIFUGAL PUMPS