TY - JOUR N2 - 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 2x frequency component in the response, as well as higher frequency components, such as 3x, 4x 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. L1 - http://czasopisma.pan.pl/Content/113189/PDF/AME_2019_129679.pdf L2 - http://czasopisma.pan.pl/Content/113189 PY - 2019 IS - No 3 EP - 353 DO - 10.24425/ame.2019.129679 KW - development of fatigue crack KW - crack flexibility KW - directional (full) spectrum KW - higher harmonics KW - forward and backward whirl A1 - Shravankumar, C. A1 - Tiwari, Rajiv PB - Polish Academy of Sciences, Committee on Machine Building VL - vol. 66 DA - 2019.09 T1 - Experimental identification of cracked rotor system parameters from the forward and backward whirl responses SP - 329 UR - http://czasopisma.pan.pl/dlibra/publication/edition/113189 T2 - Archive of Mechanical Engineering ER -