IJE TRANSACTIONS A: Basics Vol. 32, No. 1 (January 2019) 123-128    Article in Press

downloaded Downloaded: 0   viewed Viewed: 75

Mohamed Amine Khaled Benalouach, A. Sahli and S. SAHLI
( Received: May 31, 2017 – Accepted: April 28, 2018 )

Abstract    The interaction of work fluid mechanics with that of the rotary system itself, basically composed of axes, bearings and rotors, is performed by inserting equivalent dynamic coefficients in the mathematical model of the rotor, the latter being obtained by the finite element method. In this paper, the dynamic coefficients of inertia, stiffness and damping of the flat seals analyzed here are evaluated, from the point of view of the dependence with the geometric characteristics of the seals and the operating conditions of the machine. Then, once incorporated into the entire rotating system model, the flow seals are also analyzed from the point of view of their influence on the overall dynamic response of the rotating machine. The mechanical seals of the cylindrical, conical and stepped type will be analyzed, determining, for this purpose, the dynamic coefficients of damping, stiffness and inertia. In addition, the influence of physical and operational parameters of the system in relation to these elements will be verified. Therefore, the modeling and analysis of flow seals are inserted in an interesting and promising way in the context of the global research theme in rotary machines.


Keywords    fluid seals, finite volume method, rotating machinery, dynamic coefficients.


References      [1]           Tower, Beauchamp. (1883) First report on friction experiments. Proceedings of the institution of mechanical engineers 34.1: 632-659. [2]           Petrov, N. P.; (1883) Friction in Machines and the Effect of Lubricant, Inzenernii Zhurnal, St. Petersburg, Vol. 1, pp. 71-140, Vol. 2, pp. 228-279, Vol. 3, pp. 377-436, Vol. 4, pp. 535-564. [3]           NORTON, R. L. (2006) Machine design, 2nd edition,  São Paulo: Bookman. [4]           HAMROCK, Bernard J., SCHMID, Steven R., et JACOBSON, Bo O. (2004) Fundamentals of fluid film lubrication. CRC press. [5]           HIRANO, Toshio, GUO, Zenglin, et KIRK, R. Gordon. (2005) Application of computational fluid dynamics analysis for rotating machinery—part ii: labyrinth seal analysis. Journal of Engineering for Gas Turbines and Power,, vol. 127, no 4, p. 820-826. [6]           HA, T.; LEE, Y.; KIM, C. (2002) Leakage and rotordynamic analysis of a high pressure floating ring seal in the turbo pump unit of a liquid rocket engine. Elsevier. [7]           CHILDS, Dara W. et WADE, Jonathan. (2004) Rotordynamic-coefficient and leakage characteristics for hole-pattern-stator annular gas seals-measurements versus predictions. TRANSACTIONS-AMERICAN SOCIETY OF MECHANICAL ENGINEERS JOURNAL OF TRIBOLOGY, vol. 126, no 2, p. 326-333. [8]           KWANKA, K. (2000) Dynamic coefficients of stepped labyrinth gas seals. Journal of Engineering for Gas Turbines and Power, v. 122, pp. 473-477. [9]           STAUBLI, Thomas et BISSIG, Matthias. (2001) Numerically calculated rotor dynamic coefficients of a pump rotor side space. In : International Symposium on Stability Control of Rotating Machinery (ISCORMA), South Lake Tahoe, CA,  p. 20-24. [10]         DERELLI, Y.; ESER, D. (2006) Effects of shear stress forces to rotordynamic coefficients in staggered labyrinth seals. Journal of Power and Energy, v. 220, Part A, pp. 387-394. [11]         PUGACHEV, Alexander O. et DECKNER, Martin. (2010) CFD prediction and test results of stiffness and damping coefficients for brush-labyrinth gas seals. In : ASME Turbo Expo 2010: Power for Land, Sea, and Air. American Society of Mechanical Engineers, p. 175-185. [12]         PUGACHEV, Alexander O., KLEINHANS, Ulrich, et GASZNER, (2012) Manuel. Prediction of rotordynamic coefficients for short labyrinth gas seals using computational fluid dynamics. Journal of Engineering for Gas Turbines and Power, vol. 134, no 6, p. 062501. [13]         HASEGAWA, Noriyuki, YOSHIOKA, Hayato, et SHINNO, Hidenori. (2016) Noncontact gravity compensator with magnetic fluid seals. Journal of Advanced Mechanical Design, Systems, and Manufacturing, vol. 10, no 5, p. JAMDSM0078-JAMDSM0078. [14]         YANG, Xiao Long et LI, De Cai., (2016) Experimental investigation of diverging stepped magnetic fluid seals with large sealing gap. International Journal of Applied Electromagnetic and Mechanics, vol. 50, no 3, p. 407-415. [15]         SHEN, X.Y.; JIA, J. H.; ZHAO, M.; JING, J. P., (2008) Numerical and experimental analysis of the rotor bearing-seal system. Journal of Mechanical Engineering Science v. 222, part C, pp. 1435-1441. [16]         PENNACCHI  P, BACHSCHMID N, et TANZI E, (2009) Light and short arc rubs in rotating machines: Experimental tests and modeling. Mechanical Systems and Signal Processing, vol. 23, no 7, p. 2205-2227. [17]         CHENG, Mei, MENG, Guang, et JING Jianping, (2007) Numerical and experimental study of a rotor–bearing–seal system. Mechanism and Machine Theory, vol. 42, no 8, p. 1043-1057. [18]         BROL, K. B, (2011) Modeling and Analysis of Flow Seals Applied to Rotary Machines, Dissertation (Master's Degree in Mechanical Engineering) - Campinas State University, Campinas. [19]         CHILDS, D. W, (1993) Turbo machinery Rotordynamic: Phenomena, Modeling, and Analysis; John Wiley & Sons, New York. [20]         FOX, R.W.; MCDONALD, A. T .; PRITCHARD, P. J, (2006) Introduction to fluid mechanics; LTC, 6a Edition. [21]         MORAN, M. J.; SHAPIRO, H. N, (2002) Principles of thermodynamics for engineering; LTC, 4th edition. [22]         LOMAKIN A A, (1958) Calculation of critical speeds and securing of the dynamic stability of hydraulic high-pressure machines with reference of the forces arising in the gap seals. Energomashinostroenie, 4.1. [23]         CHILDS, Dara W, DRESSMAN John B, (1985) Convergent-tapered annular seals: analysis and testing for rotordynamic coefficients. ASME J. Tribol, vol. 107, no 3, p. 307-316.

International Journal of Engineering
E-mail: office@ije.ir
Web Site: http://www.ije.ir