Analytical, Numerical, and Experimental Research Approaches to Influence of Vibrations on Hydroelastic Processes in Centrifugal Pumps

The problem under research is that of unpredictable modes occurring in two-stage centrifugal hydraulic pump as a result of hydraulic processes caused by vibrations of structural components. Numerical, analytical and experimental approaches are considered. A hypothesis was developed that the problem of unpredictable pressure decrease at the second stage of centrifugal pumps is caused by cavitation effects occurring upon vibration. The problem has been studied experimentally and theoretically as of today. The theoretical study was conducted numerically and analytically. Hydroelastic processes in dynamic “liquid – deformed structure” system were numerically modelled and analysed. Using ANSYS CFX program engineering analysis complex and computing capacity of a supercomputer the cavitation parameters were established to depend on vibration parameters. An influence domain of amplitudes and vibration frequencies on concentration of cavitation bubbles was formulated. The obtained numerical solution was verified using CFM program package developed in PNRPU. The package is based on a differential equation system in hyperbolic and elliptic partial derivatives. The system is solved by using one of finite-difference method options – the particle-in-cell method. The method defines the problem solution algorithm. The obtained numerical solution was verified analytically by model problem calculations with the use of known analytical solutions of in-pipe piston movement and cantilever rod end face impact. An infrastructure consisting of an experimental fast hydro-dynamic processes research installation and a supercomputer connected by a high-speed network, was created to verify the obtained numerical solutions. Physical experiments included measurement, record, processing and analysis of data for fast processes research by using National Instrument signals measurement system and Lab View software. The model chamber end face oscillated during physical experiments and, thus, loaded the hydraulic volume. The loading frequency varied from 0 to 5 kHz. The length of the operating chamber varied from 0.4 to 1.0 m. Additional loads weighed from 2 to 10 kg. The liquid column varied from 0.4 to 1 m high. Liquid pressure history was registered. The experiment showed dependence of forced system oscillation amplitude on loading frequency at various values: operating chamber geometrical dimensions, liquid column height and structure weight. Maximum pressure oscillation (in the basic variant) amplitudes were discovered at loading frequencies of approximately 1,5 kHz. These results match the analytical and numerical solutions in ANSYS and CFM.

• Dinara F. Gaynutdinova
• Vladimir Ya Modorsky
• Nikolay A. Shevelev

• Computing experiment
• hydroelasticity
• physical experiment
• vibration.

[1] A. I. Gulienko, The equations of fluid motion in the vibrating pipelines of hydraulic systems. Mathematical models of working processes in hydro pneumatic systems, 1981.
[2] V. A. Sherstyannikov A.I. Gulienko, V.M. Kalnin, Forced oscillations of fluid pressure in the hydraulic system by vibrations. Proceedings 895, ZIAM, 1980.
[3] Davydov Yu.M. Belozerkovsky O.M., The method of large particles in gas dynamics. Nauka, Moscow, 1982.
[4] Xiu-Tian Y. Guoyuan, Z., Analysis of two phase flow in liquid oxygen hybrid journal bearings for rocket engine turbopumps. Industrial Lubrication and Tribology, 66, 2014.
[5] Wood J.R. Strazisar A.J. Hathaway M.D., Chriss R.M., Experimental and computational investi- gation of the nasa low-speed centrifugal compressor flow field. AMSE journal of Turbomachinery, 115:527–542, 1993.
[6] Schlcker E. Ismaier A., Fluid dynamic interaction between water hammer and centrifugal pumps. Nuclear Engineering and Design, 239:3151 3154, 2009.
[7] Kortnev A.V. Kortnev A.A., Makarov V.K., About the distribution of bubbles under ultrasonic cavitation. The proceedings of acoustic institute of AN SSSR, 1969.
[8] Chaplygin V.Ya. Matveenko A.M., The research of fluid motion in asymmetric hydraulic channels. The bulletin of Moscow Aviation Institute, 19:5864, 2012.
[9] Chaplygin V.Ya. Matveenko A.M., The way of creating high pressure and super pressure and its device. patent 2502894, 2012.
[10] Chaplygin V.Ya. Matveenko A.M., Cavitation in the gaps considering liquid viscosity and the acceleration of structural elements. The proceedings of XX International Symposium Dynamic and technological issues of mechanics of structures and continuum named after A.G. Gorshkov, pages 142–144, 2014.
[11] Vladimir Ya. Modorsky, The solution of engineering problems on high performance computing com- plex of the Perm National Research Polytechnic University, edited by V.Ya. Modorsky. Publishing of the Perm National Research Polytechnic University, Perm, 2014.
[12] V.Ya. Modorsky and Yu.V. Sokolkin, Gas Elastic Processes in Power Plants. Nauka, Moscow, 2007.
[13] Hergt P., Pump research and development: past, present and future. Trans. ASME, 121:248–253, 1999.
[14] Vrtanik D. Resnik D. Moek M. Dolan T. Brajkovi R. Kriaj D. Pear, B., Micropump operation at various driving signals: numerical simulation and experimental verification. Microsystem Tech- nologies, 2014.
[15] Zlotkin Sh.L. Fluid motion in a vibrating pipeline. Proceedings VVIA named after N.E. Zhukovsky, 311, 1948.
[16] D.F. Gaynutdinova, A.V. Kozlova, V.Ya. Modorsky, E.V. Mekhanoshina, Numerical simulation of cavitation effects in the action of vibration. Scientific and Technical Bulletin of Povolzhye. No. 6 2013 – Kazan: Scientific and Technical Bulletin of Povolzhye, 2013. – pp. 219-223.
[17] D.F. Gaynutdinova, V.Ya. Modorsky, G.F. Masich, Design of the technological platform for experimental and computing research of the fast-proceeding hydroelasticity processes. Scientific and Technical Bulletin of Povolzhye. No. 5 2014 – Kazan: Scientific and Technical Bulletin of Povolzhye, 2014 – pp. 155-158.
[18] Gaynutdinova D.F., Modorsky V.Ya., Kozlova A.V., Computing modeling of area of emergence of cavitation at vibration.. Scientific and Technical Bulletin of Povolzhye. No. 6 2014 – Kazan: Scientific and Technical Bulletin of Povolzhye, 2014. – pp. 127-129.
[19] I.P. Ginzburg Aerogasdynamics. – M.: Vysshaya Schkola, 1966 – 404 pp.
[20] Gaynutdinova D.F., Modorsky V.Ya., Petrov V.Yu., Vibration and wave processes in view of non-linear deformation of components in aircraft engine hydraulic systems. APM 2015. Advanced Problems in Mechanics: proceedings of the XLIII Summer School – Conf., June 22-July 27 2015, St. Petersburg / Inst. for Problems in Mechanical Engineering. – St. Petersburg, 2015. – pp. 100-107.
[21] D.F. Gaynutdinova, V.Ya. Modorsky, G.F. Masich, Infrastructure of Data Distributed Processing in High-Speed Process Research Based on Hydroelasticity Task. Procedia Computer Science, 2015, vol. 66.
[22] S.I. Perevoshchikov, Calculation of the coefficient of cavitation specific speed centrifugal pumps. Higher Educational Institutions News. Oil and Gas. №. 2 2000 – Tyumen: Tyumen State oil and gas University, 2000 – pp. 63-71.