Experimental identification of cracked rotor system parameters from the forward and backward whirl responses

• Autorzy: Shravankumar C. , Tiwari Rajiv

Identyfikatory

DOI

10.24425/ame.2019.129679

• Języki publikacji: EN

Abstrakty

EN

In the present work, an experimental investigation of a transverse fatigue crack has been carried out. A mathematical modelling of cracked rotor system along with the measured vibration is used to find crack parameters that not only detect the fault but also quantify it. Many experimental studies on cracks considered the crack as a slit or notch, which remains open. However, such flaws do not mimic a fatigue crack behavior, in which crack front opens and closes (i.e., breathes in a single revolution of the rotor). The fatigue crack in rotors commonly depicts 2× frequency component in the response, as well as higher frequency components, such as 3×, 4× and so on. In rotors, both forward and backward whirling take place due to asymmetry in rotor, and thus the fatigue crack gives the forward and backward whirl for all such harmonics. A rotor test rig was developed with a fatigue crack in it; rotor motions in two orthogonal directions were captured from the rig at discrete rotor angular speeds using proximity probes. The directional-spectrum processing technique has been utilized to the measured displacements to get its forward and backward whirl components. Subsequently, it is executed in a mathematical model-based estimation procedure to obtain the crack forces, residual unbalances, and remaining rotor system unknown variables. Estimation of crack forces during rotation of the shaft gives its characteristics, which can be used further to develop newer crack models.

Słowa kluczowe

EN

development of fatigue crack; crack flexibility; directional (full) spectrum; higher harmonics; forward and backward whirl

PL

rozwój pęknięć zmęczeniowych; spektrum kierunkowe (pełne); wyższa harmoniczna

• Wydawca: Komitet Budowy Maszyn PAN
• Czasopismo: Archive of Mechanical Engineering
• Rocznik: 2019
• Tom: Vol. LXVI, nr 3
• Strony: 329--353
• Opis fizyczny: Bibliogr. 27 poz., rys., tab., wykr.

Twórcy

autor

Shravankumar C.

• Department of Mechanical Engineering, Indian Institute of Technology Guwahati, Guwahati – 781039, India

autor

Tiwari Rajiv

• Department of Mechanical Engineering, Indian Institute of Technology Guwahati, Guwahati – 781039, India

Bibliografia

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Uwagi

Opracowanie rekordu ze środków MNiSW, umowa Nr 461252 w ramach programu "Społeczna odpowiedzialność nauki" - moduł: Popularyzacja nauki i promocja sportu (2020).