Authors:
Mihir Barman,Gamini Suresh,Kondeti Sravanth,Nandure Narayan Rao,DOI NO:
https://doi.org/10.26782/jmcms.2020.07.00059Keywords:
Campbell diagram,Natural frequency,Critical speed, Modes,Torsional stiffness,Abstract
The main aim of this paper is to avoid the critical speed at low rotational velocities for three different cases, i.e. shaft without rotor, single rotor system and two rotor system. The critical speeds of these rotor systemsareanalyzed with two boundary conditions, viz. one end supported, both ends supported. Moreover, the rotors are mounted at two different positions: single rotor is placed at middle of the shaft and the same rotor is split into two halves and kept at equal distance from the either end of shaft. This critical speed analysis is carried out on both solid and hollow shafts. The range of rotational speed for the analyses considered in between 0 to 5000 rpm.The critical speeds of various rotor systems are studied using Campbell diagram and it is observed that, the critical speeds are altered by changing the boundary conditions and replacing the solid shaft with hollow shaft of same torsional stiffness as well.Refference:
I. Aditya Sukma Nugraha, Imam Djunaedi, and Hilman Syaeful Alam, “Evaluation of Critical Speed of the Rotor Generator System Based on ANSYS”, Applied Mechanics and Materials, Vols. 799-800, pp 625-628, 2015.
II. Bing Bai, Lixiang Zhang, Tao Guo, Chaoqun Liu, “Analysis of Dynamic Characteristics of the Main Shaft System in a Hydro-turbine Based on ANSYS”, Procedia Engineering, volume 31, pp 654 – 658, 2012.
III. Harisha S., Y.J. Suresh, “Rotor Dynamics Analysis of a Multistage Centrifugal Pump”, International Journal of Innovative Research in Science, Engineering and Technology, Vol. 3, Issue 9, 2014.
IV. Hilman Syaeful Alam, Bahrudin, Anto Tri Sugiarto, “Dynamic Analysis of Shaft System of Micro Bubble Generating Pump”, International Journal of Materials, Mechanics and Manufacturing, Vol. 5, pp 205-208, 2017.
V. Korody Jagannath, “Evaluation of Critical Speed of Generator Rotor with external load”, International Journal of Engineering Research and Development, Volume 1, Issue 11, pp 11-16, 2012.
VI. L. M. Greenhill, G. A. Cornejo,“Critical Speeds Resulting from Unbalance Excitation of Backward Whirl”, Design Engineering Technical Conferences, Volume 3, pp. 991-1000, ASME 1995.
VII. Muhammad T. H., Umar S. U, Aisha Sa’ad, “FEA and Modal Analysis of a Damped Flywheel with Unbalanced Masses”, Applications of Modelling and Simulation, Vol 4, pp 21-30, 2020.
VIII. Nagaraju Tenali, Srinivas Kadivendi, “Rotor Dynamic Analysis of Steam Turbine Rotor Using ANSYS”, International Journal of Mechanical Engineering & Robotics Research, Vol. 3, 2014.
IX. Pingchao Yu, Dayi Zhang, Yanhong Ma, Jie Hong, “Dynamic modeling and vibration characteristics analysis of the aero-engine dual-rotor system with Fan blade out”, Mechanical Systems and Signal Processing, Volume 106, pp 158–175, 2018.
X. R. Tamrakar, N. D. Mittal, “Campbell diagram analysis of open cracked rotor”, Engineering Solid Mechanics, Volume 4, issue 3, pp 159-166, 2016.
XI. Shuji Tanaka, Masayoshi Esashi, Kousuke Isomura, Kousuke Hikichi, Yuki Endo, Shinichi Togo “Hydroinertia Gas Bearing System to Achieve 470 m/s Tip Speed of 10 mm Diameter Impellers”, Journal of Tribology, Volume 129, pp 655-659, 2007.
XII. Silani, M., Ziaei-Rad, S., Talebi, H., “Vibration analysis of rotating systems with open and breathing cracks”, Applied Mathematical Modelling, 37(24), 9907-9921, 2013.