Application of Particle Dampers on a Scaled Wind Turbine Generator to Improve Low-Frequency Vibro-Acoustic Behavior

The purpose of this paper is to introduce a honeycomb damping plate (HCDP) concept based on the particle damping technique to reduce the low-frequency vibration response of wind turbine generators. The HCDP cells contain granular materials and are mounted at different positions on the generator to reduce the transmission of vibrations from stator ring to stator arm. To investigate the efficiency of the HCDP concept in the laboratory, a small-scale replica inspired by the original wind turbine generator is used as reference geometry. The efficiency of the vibration attenuation by using the HCDP concept is experimentally investigated with the help of a laser scanning vibrometer device. In this contribution, the influence of four different granular materials on the vibration attenuation is experimentally investigated. Furthermore, the influence of HCDP positioning on the transmission path damping is analyzed. Apart from this, the effect of single-unit (SU) and multi-unit (MU) HCDP on the frequency response of the generator is also studied. The experimental approach in this paper shows good damping properties of the HCDP concept for reducing the vibration amplitude.

Effect of sphere configurated particle damper on tribological properties during boring of hardened steel

Tool vibration is the most unfavourable element in the boring operation, as it contributes to poor surface finish, excessive tool wear, and progressive cutting force. Tool vibration mainly occurs due to the overhanging length of the boring tool and to overcome this factor an appropriate mechanism has to be established which helps to increase the production and quality of the product in manufacturing sector. An impact particle damper with variable material spheres, sphere diameter, and sphere location in a boring tool is fabricated in this work. A 27 run experiments were conducted to find the effect of impact particle damping on tribological properties during boring process. The results shows that impact particle damper increases the rigidity of the tool holder which enhances the tribological properties. The sphere in the boring tool will collide with one another thereby suppressing the tool vibration efficiently.

ADDITIVE REFURBISHMENT OF A VIBRATION-LOADED STRUCTURAL COMPONENT

In the event of damage to additively manufactured components whose shape cannot be produced by machining, an additive repair can potentially be not only ecologically but also ecologically more favorable than the production of a new component. In addition, a number of hurdles that otherwise often impede the use of additive repair, e.g. the availability of the material of the damaged component for the additive process, are eliminated. As far as the authors are aware, this publication is the first to present a process for the additive refurbishment of additively manufactured components using the example of a wheel carrier. In this context, the possibility of increasing the fatigue strength of a structural component in refurbishment is discussed for the first time. To increase the fatigue strength of the wheel carrier, the chosen approach is to integrate the effect of particle damping into the component. Particularly in the case of components subjected to bending stresses, the effect of particle damping can be integrated into the component's interior without having to accept a significant loss of strength.

Effect of Particle Material, Size and Filling Percentage on Particle Damping Phenomenon for Gear Transmission System

Particle damping is a passive vibration control technology. At the present stage, particle damping technology is developing especially in machinery and aerospace fields. For studying the particle damping effect different parameters such as particle material, size and filling percentage is used. One of the applications for particle damping phenomenon is gear transmission system. For simulation of particle damping discrete element method (DEM) software is used. The simulation results have been validated by comparing with experimental results of a physical system. Find damping effect due to particle damping from simulation and experimentation.

Damping prediction of particle dampers for structures under forced vibration using effective fields

Particle damping is a promising damping technique for a variety of technical applications. However, their non-linear behavior and multitude of influence parameters, hinder currently its wide practical use. So far, most researchers focus either on determining the energy dissipation inside the damper or on the overall damping behavior when coupled to a structure. Indeed, currently almost no knowledge exchange between both approaches occurs. Here, a bridge is build to combine both techniques for systems under forced vibrations by coupling the energy dissipation field and effective particle mass field of a particle damper with a reduced model of a vibrating structure. Thus, the overall damping of the structure is estimated very quickly. This combination of both techniques is essential for an overall efficient dimensioning process and also provides a deeper understanding of the dynamical processes. The accuracy of the proposed coupling method is demonstrated via a simple application example. Hereby, the energy dissipation and effective mass of the particle damper are analyzed for a large excitation range first using a shaker setup. The particle damper exhibits multiple areas of different efficiency. The underlying structure is modeled using FEM and modal reduction techniques. By coupling both parts it is shown that multiple eigenmodes of the structure are highly damped using the particle damper. The damping prediction using the developed coupling procedure is validated via experiments of the overall structure with particle damper.

Design and Development of Particle Friction and Impact Damping for Spur Gear Drive

Gear transmission system plays an important role in many of the mechanical systems. Vibration is the major problem and unavoidable in gear transmission system because high speed and heavy loading condition. High temperature and harsh working condition limits the other vibration absorption methods. Particle friction & impact damping is passive method of vibration absorption. Ordinary particle damping method gives the random movement of particles. In this research holes are provided to the gear and put cylindrical impact particles in particular hole gives the friction and impact effect to absorb the vibration. The mathematical analysis is formulated for the system also run MATLAB program and found out plot for displacement v/s time. DEM simulation carried out using EDEM software which is used to perform simulations at different speed and to analyze the energy dissipation during particle collisions and compared the energy absorbed by the particles of different materials for varying speed.