PSI - Issue 18

Goran Vukelic et al. / Procedia Structural Integrity 18 (2019) 406–412 Author name / Structural Integrity Procedia 00 (2019) 000–000

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is 495.26 MPa, Fig. 5 . In accordance with DIN 3991, analytically calculated tooth root stress, σ F , and permissible tooth root stress, σ FP , for the pinion are σ F = 215,74 MPa and σ FP = 481,63 MPa. The permissible value of contact stress, σ HP , and existing surface pressure, σ PHP , are σ HP = 574,96 MPa and σ PHP = 1011,76 MPa , respectively. Maximum surface pressure obtained numerically is 914,16 MPa, Fig 6. Results differ by no more than 3% for the equivalent stress and 9% for the existing surface pressure giving confidence in further use of FE model.

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Fig. 5. Spiral bevel gear pair: a) FE model with mesh, b) pinion equivalent stress

Fig. 6. Pinion surface contact pressure

Besides the FE model of undamaged gear pair, the 3D model of the damaged pinion flanks, as well as the model of the damaged pinion teeth tip were also considered, Fig 7., in order to obtain time varying mesh stiffness (TVMS)[7], Fig. 8., asan important parameter of the system condition.The quasi-static algorithm (QSA) is used for computing the TVMS[9].