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1 – 3 of 3Romain Corcolle, Erwan Salaün, Frédéric Bouillault, Yves Bernard, Claude Richard, Adrien Badel and Daniel Guyomar
To provide a model that allows testing and understanding special damping techniques.
Abstract
Purpose
To provide a model that allows testing and understanding special damping techniques.
Design/methodology/approach
The finite element modeling takes into account the piezoelectric coupling. It is used with a non linear electrical circuit. The approach leads to an accurate tool to observe the behavior of the non linear damping techniques such as synchronized switch damping.
Findings
The model has been validated by comparison with Ansys® but the CPU time required for the model is around one hundred times shorter.
Research limitations/implications
The proposed model is 1D and the assumptions to use it are not verified for all structures.
Practical implications
The authors obtain a useful tool for the design of damping structures (for example to find the best localisation of the piezoelectric patches and to test electrical circuits).
Originality/value
The model is used for the design and conception of damping as well as for harvesting structures.
Details
Keywords
Xavier Mininger, Mohamed Gabsi, Michel Lécrivain, Elie Lefeuvre, Claude Richard, Daniel Guyomar and Frédéric Bouillault
This paper seeks to study the feasibility of a stator vibration damping using piezoelectric (PZT) actuators applied to switched reluctance motors (SRM).
Abstract
Purpose
This paper seeks to study the feasibility of a stator vibration damping using piezoelectric (PZT) actuators applied to switched reluctance motors (SRM).
Design/methodology/approach
A single‐phase structure without moving rotor, but with the same shape as an SRM stator, is introduced to simplify the study and the experimental measurements. Both analytical and finite element methods are used to detail the chosen location and design of the PZT actuators for this structure.
Findings
Experimental results show that PZT actuators with a low voltage allow the decrease of the vibration level due to the electromagnetic forces.
Research limitations/implications
To decrease the vibration level of the SRM stator in the real use of the machine, a closed loop system is necessary. Future works consist of the design of a closed loop numerical controller using an acceleration sensor as strain information.
Practical implications
The proposed damping method gives a new solution for the SRM noise problem that can be useful for people working on noise reduction on this machine.
Originality/value
So far vibration damping of SRM stator was obtained using a command or a geometry “acoustically” optimised, or active vibration with an auxiliary coil. The solution presented here applies PZT vibration damping to the stator with a thickness more important than the one of classical plates used for PZT damping applications.
Details
Keywords
Caroline Nore, Houda Zaidi, Frederic Bouillault, Alain Bossavit and Jean-Luc Guermond
The purpose of this paper is to present a new formulation for taking into account the convective term due to an imposed velocity field in the induction equation in a code based on…
Abstract
Purpose
The purpose of this paper is to present a new formulation for taking into account the convective term due to an imposed velocity field in the induction equation in a code based on Whitney elements called DOLMEN. Different Whitney forms are used to approximate the dependent variables. The authors study the kinematic dynamo action in a von Kármán configuration and obtain results in good agreement with those provided by another well validated code called SFEMaNS. DOLMEN is developed to investigate the dynamo action in non-axisymmetric domains like the impeller driven flow of the von Kármán Sodium (VKS) experiment. The authors show that a 3D magnetic field dominated by an axisymmetric vertical dipole can grow in a kinematic dynamo configuration using an analytical velocity field.
Design/methodology/approach
Different Whitney forms are used to approximate the dependent variables. The vector potential is discretized using first-order edge elements of the first family. The velocity is approximated by using the first-order Raviart-Thomas elements. The time stepping is done by using the Crank-Nicolson scheme.
Findings
The authors study the kinematic dynamo action in a von Kármán configuration and obtain results in good agreement with those provided by another well validated code called SFEMaNS. The authors show that a 3D magnetic field dominated by an axisymmetric vertical dipole can grow in a kinematic dynamo configuration using an analytical velocity field.
Originality/value
The findings offer a basis to a scenario for the VKS dynamo.
Details