Dynamic behavior of an imbalanced and warped Jeffcott rotor with asymmetric stiffness

• Autorzy: Lin, F. , Meng, G. , Fang, T.
• Języki publikacji: EN

Abstrakty

EN

The dynamic behaviour of an imbalanced and warped Jeffcott rotor with asymmetric stiffness was studied theoretically and experimentally. The rotor response was analyzed and discussed under different rotating speeds and angle ranges between the directions of the bend and imbalance. It was noted that the angle between the directions of the warp and the imbalance plays a key role in controlling the rotor response and effect of the angle varied by the magnitude of bend. If the angle is larger than [...] and smaller than [...] in radian, the rotor response will decrease due to imbalance. Particularly for sufficiently large angles, the response amplitude will decrease with increasing rotating speed. This effect will take place before passing the first critical rotating speed, if the magnitude of the warp is smaller than the eccentricity; and will take place after passing the first critical rotating speed, if the magnitude of the warp is larger than the eccentricity. A double frequency response also happened in an imbalanced rotor with initial bow and asymmetric stiffness; the supposed stationary response will lose its stability as the rotating speed lies in the range between the first two critical speeds. Good agreement was achieved between the numerical solutions and the experimental results to verify the proposed model capability, which may contribute to the diagnosis of asymmetric stiffness and the residual warp of the rotor.

Słowa kluczowe

PL

sztywność niesymetryczna; smarowanie; łożyska ślizgowe

EN

rotor dynamics; residual warp; imbalance; asymmetrical stiffness

• Czasopismo: International Journal of Applied Mechanics and Engineering
• Rocznik: 2007
• Tom: Vol. 12, no 4
• Strony: 1039-1048
• Opis fizyczny: Bibliogr. 8 poz., wykr.

Twórcy

autor

Lin, F.

autor

Meng, G.

autor

Fang, T.

• Institute of Mechanical and Electronic Engineering Wuhan University of Science and Engineering l Fangzhi Rd, Wuhan 430073, P.R. CHINA,

Bibliografia

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