ABSTRACT
In the increasing need for energy saving worldwide, the designing process of turbomachinery, as an essential part of thermal and hydroenergy systems, goes in the direction of enlarging efficiency. Therefore, the optimization of turbomachinery designing strongly affects the energy efficiency of the entire system. In the designing process of turbomachinery blade profiling, the model of axisymmetric fluid flows is commonly used in technical practice, even though this model suits only the profile cascades with infinite number of infinitely thin blades. The actual flow in turbomachinery profile cascades is not axisymmetric, and it can be fictively derived into the axisymmetric flow by averaging flow parameters in the blade passages according to the circular coordinate. Using numerical simulations of flow in turbomachinery runners, its operating parameters can be preliminarily determined. Furthermore, using the numerically obtained flow parameters in the blade passages, averaged axisymmetric flow surfaces in blade profile cascades can also be determined. The method of determination of averaged flow parameters and averaged meridian streamlines is presented in this paper, using the integral continuity equation for averaged flow parameters. With thus obtained results, every designer can be able to compare the obtained averaged flow surfaces with axisymmetric flow surfaces, as well as the specific work of elementary stages, which are used in the procedure of blade designing. Numerical simulations of flow in an exemplary axial flow pump, used as a part of the thermal power plant cooling system, were performed using Ansys CFX. [Projekat Ministarstva nauke Republike Srbije, br. TR33040: Revitalization of existing and designing new micro and mini hydropower plants (from 100 kW to 1000 kW) in the territory of South and Southeast Serbia]
KEYWORDS
PAPER SUBMITTED: 2012-04-26
PAPER REVISED: 2012-06-25
PAPER ACCEPTED: 2012-07-05
THERMAL SCIENCE YEAR
2012, VOLUME
16, ISSUE
Supplement 2, PAGES [S577 - S591]
- Babić, M., Stojković S., Basics of Turbomachinery: operating principles and mathematical modeling, University of Kragujevac, Naučna knjiga, Beograd, Serbia, 1990.
- Lakshminarayana, B., Fluid Dynamics and Heat Transfer of Turbomachinery, John Wiley & Sons, Inc., New York, USA, 1996.
- Krsmanović Lj., Gajić A., Turbomachinery - theoretical basics, University of Belgrade, Faculty of Mechanical Engineering Belgrade, Belgrade, Serbia, 2005.
- Tanata S., Hiratani F., Furukawa M., Axisymmetric Viscous Flow Modeling for Meridional Flow Calculation in Aerodynamic Design of Half-Ducted Blade Rows, Memoirs of the Faculty of Engineering, Kyushu University, Vol.67 (2007), No.4.
- Bogdanović-Jovanović J., Milenković D., Bogdanović B., Numerical simulation of flow and operating characteristics of axial flow pump, Proceedings, 32. Congress HIPNEF 2009,Vrnjačka Banja, Serbia, 2009, pp. 217-224.
- Casey M., Best practice advice for turbomachinery internal flows, QNET-CFD Network Newsletter (A Thematic Network For Quality and Trust in the Industrial Application of CFD) (2004), Volume 2, No.4 pp.40-46.
- Ferziger J.H., Peric M., Computational methods for fluid dynamics, third edition, Springer, 2002.
- Etinberg I.E., Rauhman B.S., Hydrodynamics of hydraulic turbines, Sent Petersburg, Russia, 1978. (in Russian).
- Bogdanović B., Bogdanović-Jovanović J., Spasic Ž., Designing of Low Pressure Axial Flow Fans with Different Specific Work of Elementary Stages, Proceedings, The International Conference - Mechanical Engineering in XXI Century, Nis, Serbia, 2010, pp. 99102.
- Bogdanović B., Bogdanović-Jovanović J., Todorovic N., Program for determination of unequal specific work distribution of elementary stages in the low-pressure axial-flow fan design procedure, Facta Universitatis, Series: Mechanical Engineering, Vol. 9 (2011), No 2, pp. 149 - 160, UDC 621.63.