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5 articles for “Whirl speed”
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Influence of Internal and External Dampings on Shaft Whirl Speeds
Abstract: A mathematical model is developed for the estimation of rotor forward and backward whirl speeds by considering the stationary and rotational dampings. Stationary damping includes external viscous damping in the bearings and rotational damping includes internal viscous and hysteretic damping in the shaft material. The rotors in gas turbines and steam turbines commonly used in military and commercial rotating machines operate at high speeds. These rotors are provided with a …
Published in Trends in Machine design · Vol. 3, Issue 3, 2016 · pp. 1–11 Read article
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Study on Influence of Different Forms of Damping and Operating Temperature on Whirling Speeds of Rotors
Abstract: Accurate prediction of rotor whirl speeds is fundamentally important in the design of rotating machinery. There has been an impressive progress in the study of rotor dynamics in the last decade. The use of finite elements for the simulation of rotor system makes it possible to handle complex problems. Rotating shaft tends to bow out at certain speeds and whirl in a complicated manner. This phenomenon results from various causes …
Published in Trends in Machine design · Vol. 4, Issue 2, 2017 · pp. 41–55 Read article
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Experimental Investigation of Shaft Whirl Carrying 3 Rotors
Abstract: This paper deals with the study of whirling of shaft with three rotors. Natural frequency of the system is found by impact hammer test followed by identifying the speed at which whirling occurs in the system. Experimental results were verified by using Dunkerley's method for natural frequency. Rayleigh-Ritz equation is used to find out the critical speed of the shaft and hence to validate with experimental result.Keywords: Whirling, Natural frequency, …
Published in Trends in Mechanical Engineering & Technology · Vol. 5, Issue 2, 2015 · pp. 17–21 Read article
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Stabilizing Internal Damping in Hydrodynamic Bearings using Elegant Control Strategies
Abstract: The implementation of elegant control strategies to stabilize the internal damping problem in hydrodynamic bearing has been proposed in this paper. This implementation deals or gives an advantage of good stability of hydrodynamic bearing, even at critical or threshold speeds where an unstable whirl occurs leading to instability assisted greatly by this internal damping factor. Related stability graphs have been plotted using MATLAB 2013 and models have been designed using …
Published in Journal of Control & Instrumentation · Vol. 7, Issue 3, 2016 · pp. 44–49 Read article
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Stabilizing Varying Eccentricity Problem in Hydrodynamic Bearings Using Elegant Control Strategies
Abstract: The implementation of elegant control strategies to stabilize varying eccentricity problem in hydrodynamic bearing has been proposed in this paper. This implementation deals or gives an advantage of good stability of hydrodynamic bearing, even at critical or threshold speeds where an unstable whirl occurs leading to instability assisted greatly by this varying eccentricity factor. Hence in this paper, we take eccentricity as a function of variation and try to stabilize …
Published in Journal of Instrumentation Technology & Innovations · Vol. 6, Issue 3, 2016 · pp. 14–20 Read article