[article]
| Titre : |
Multiharmonic forced response analysis of a turbine blading coupled by nonlinear contact forces |
| Type de document : |
texte imprimé |
| Auteurs : |
Christian Siewert, Auteur ; Lars Panning, Auteur ; Jörg Wallaschek, Auteur |
| Année de publication : |
2011 |
| Article en page(s) : |
09 p. |
| Note générale : |
Génie Mécanique |
| Langues : |
Anglais (eng) |
| Mots-clés : |
Blades Failure (mechanical) Fatigue Frequency-domain analysis Galerkin method Iterative methods Mechanical contact Reduced order systems Steam turbines Thermal stresses Time-domain Vibrations |
| Index. décimale : |
620.1 Essais des matériaux. Défauts des matériaux. Protection des matériaux |
| Résumé : |
In turbomachinery applications, the rotating turbine blades are subjected to high static and dynamic loads. The static loads are due to centrifugal stresses and thermal strains whereas the dynamic loads are caused by the fluctuating gas forces resulting in high vibration amplitudes, which can lead to high cycle fatigue failures. Hence, one of the main tasks in the design of turbomachinery blading is the reduction in the blade vibration amplitudes to avoid high dynamic stresses. Thus, coupling devices like underplatform dampers and tip shrouds are applied to the blading to reduce the vibration amplitudes and, therefore, the dynamic stresses by introducing nonlinear contact forces to the system. In order to predict the resulting vibration amplitudes, a reduced order model of a shrouded turbine blading is presented including a contact model to determine the nonlinear contact forces. To compute the forced response, the resulting nonlinear equations of motion are solved in the frequency domain using the multiharmonic balance method because of the high computational efficiency of this approach. The transformation from the time domain into the frequency domain is done by applying Galerkin's method in combination with a multiharmonic approximation function for the unknown vibration response. This results in an algebraic system of nonlinear equations in the frequency domain, which has to be solved iteratively in order to compute the vibration response. The presented methodology is applied to the calculation of the forced response of a nonlinear coupled turbine blading in the frequency domain. |
| DEWEY : |
620.1 |
| ISSN : |
0742-4795 |
| En ligne : |
http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JETPEZ00013 [...] |
in Transactions of the ASME . Journal of engineering for gas turbines and power > Vol. 132 N° 8 (Août 2010) . - 09 p.
[article] Multiharmonic forced response analysis of a turbine blading coupled by nonlinear contact forces [texte imprimé] / Christian Siewert, Auteur ; Lars Panning, Auteur ; Jörg Wallaschek, Auteur . - 2011 . - 09 p. Génie Mécanique Langues : Anglais ( eng) in Transactions of the ASME . Journal of engineering for gas turbines and power > Vol. 132 N° 8 (Août 2010) . - 09 p.
| Mots-clés : |
Blades Failure (mechanical) Fatigue Frequency-domain analysis Galerkin method Iterative methods Mechanical contact Reduced order systems Steam turbines Thermal stresses Time-domain Vibrations |
| Index. décimale : |
620.1 Essais des matériaux. Défauts des matériaux. Protection des matériaux |
| Résumé : |
In turbomachinery applications, the rotating turbine blades are subjected to high static and dynamic loads. The static loads are due to centrifugal stresses and thermal strains whereas the dynamic loads are caused by the fluctuating gas forces resulting in high vibration amplitudes, which can lead to high cycle fatigue failures. Hence, one of the main tasks in the design of turbomachinery blading is the reduction in the blade vibration amplitudes to avoid high dynamic stresses. Thus, coupling devices like underplatform dampers and tip shrouds are applied to the blading to reduce the vibration amplitudes and, therefore, the dynamic stresses by introducing nonlinear contact forces to the system. In order to predict the resulting vibration amplitudes, a reduced order model of a shrouded turbine blading is presented including a contact model to determine the nonlinear contact forces. To compute the forced response, the resulting nonlinear equations of motion are solved in the frequency domain using the multiharmonic balance method because of the high computational efficiency of this approach. The transformation from the time domain into the frequency domain is done by applying Galerkin's method in combination with a multiharmonic approximation function for the unknown vibration response. This results in an algebraic system of nonlinear equations in the frequency domain, which has to be solved iteratively in order to compute the vibration response. The presented methodology is applied to the calculation of the forced response of a nonlinear coupled turbine blading in the frequency domain. |
| DEWEY : |
620.1 |
| ISSN : |
0742-4795 |
| En ligne : |
http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JETPEZ00013 [...] |
|
Ajouter le résultat dans votre panier Faire une suggestion Affiner la rechercheEddy current damping / Jacob Laborenz in Transactions of the ASME . Journal of engineering for gas turbines and power, Vol. 132 N° 5 (Mai 2010)
