Optimization of design of one mass dynamic vibration absorber with stochastic system parameters pentti varpasuo fortum engineering, vantaa, finland abstract one mass dynamic vibration absorber is investigated. Optimum design of dynamic vibration absorbers for a beam. The goal of the device is to reduce vibration to acceptable levels not entirely eliminate vibration. Apr 01, 2012 by analogy, holding one leg of a vibrating tuning fork also stops the vibration of the other leg. On the usage of dynamic vibration absorbers for reduction. The behavior of dynamic vibration absorbers of conventional and novel design has been investigated experimentally and found to compare closely with prediction. Minimax optimization of dynamic pendulum absorbers for a damped primary system mohammed a. These methods require the use of many translationaltype massspring absorbers for creating a region of. The numerical calculation table has been developed with the aid of spreadsheet program excel 4.
For the love of physics walter lewin may 16, 2011 duration. Dynamic vibration absorbers are very effective to reduce vibration levels at resonance conditions. Considers the peculiarities in solving vibration absorption problems using the simplest doublemass linear model of the protected structure and absorber. First, the optimal locations where the dvas are attached are determined by modal analysis with a. In order not to introduce extra resonant frequencies, vibration absorbers or tmd are usually damped 4. Parameters optimization for a kind of dynamic vibration. A dynamic vibration absorber dva is a device consisting of an auxiliary massspringdamper system which tends to neutralise the vibration of a structure to which it is attached. Dynamic vibration absorber design for a motor and pump. I designed various dynamic absorbers for cases up to 25000 lbs and as a rule of thumb you could use an absorber mass of 5 to 10% total mass. Introduction the dynamic vibration absorber dva or tunedmass damper tmd is a widely used passive vibration control device. Dynamic vibration absorbers application with variable. The deterministic trial value for tuning ratio f has been calculated from equation 16 using values 0. Herve sonfack bouna, blaise romeo nana nbendjo laboratory of modelling and simulation in engineering, biomimetics and prototype, faculty of sciences, university of yaounde i, yaounde, cameroon.
Design of a dynamic vibration absorber for vibration. Excessive vibration levels were measured at a newly installed motor and pump assembly. Base isolator being tested at the ucsd caltranssrmd facility. The product design has a simple standalone design that requires no welding, which can be used in locations where there is no suitable surrounding steelwork. A in partial fulfillment of the requirements for the. Standards and guidelines for testing, installation, and performance of mechanical equipment have been created in order to provide attachment methods for equipment located in noise sensitive areas. To reduce the vibration of the system, the frequency of absorber should be equal to the excitation frequency. Dynamic vibration absorbers are used to reduce the undesirable vibration in many applications such as pumps, gas turbines, engine, bridge, and electrical generator.
In order to control the vibration of sheet metal parts, a passive dynamic vibration absorber is designed based on dynamic vibration absorption theory in this paper, and the performance of the vibration absorber is verified by simulation analysis. This study focuses on the optimum design of the damped dynamic vibration absorber dva for damped primary systems. Optimal cantilever dynamic vibration absorbers by timoshenko. I designed various dynamic absorbers for cases up to 25000 lbs and as a rule of thumb you could use an absorber mass of 5. Igusa analyzed the vibration control capabilities of multi ple tuned mass dampers with natural frequencies distrib uted over a frequency range 1. Citation query theory of dynamic vibration absorber citeseerx. Introduction the vibration absorber1, also called dynamic vibration absorber dva, is a mechanical device used to reduce or eliminate unwanted vibration. A smart dynamic vibration absorber for suppressing the vibration of a string supported by flexible beams. Dec 04, 2017 for the love of physics walter lewin may 16, 2011 duration. Effect of inerter in traditional and variant dynamic. On the usage of dynamic vibration absorbers for reduction of. Dynamic vibration absorbers have also been widely used in tool damping 11, 12. In many cases, the vibration amplitudes are reduced by 50%. Lowfrequency vibration control of floating slab tracks.
Two dynamic vibration absorbers are initially attached at the quarter points x250, 750 mm and one dynamic vibration absorbers at the center point x500 mm of the lower surface of the beam, respectively. The so often called vibration absorbers, which more appropriately should be called vibration neutralizers, are mechanical devices to be attached to another mechanical system, or structure, called the primary system, with the purpose of controlling, or reducing vibration and sound radiation from machines, structural surfaces and panels. This is a universal solution as it works for any frequency range. Vibration control of a plate subjected to impulsive force by platetype dynamic vibration absorbers. The dynamic vibration absorber this page demonstrates the behavior of the classical undamped dynamic absorber, introduced into the literature in 1928 by j. Integration of vibration absorbers in milling chucks. Application of a dynamic vibration absorber to a piecewise linear beam system j. Vibration absorbers are mainly used in civil engineering structures, e. Dynamic vibration absorber, optimum design, simulation i. This experiment is part of the 1b earthquake vibration of structures integrated coursework. Simple vibration neutraliser ppt mechanical engineering notes edurev is made by best teachers of mechanical engineering.
Laboratory measurements indicate fulfilment of specifications for reducing vibrations in turboprop aircraft, while the dva design could be applied to vibration. The dynamic vibration absorber was invented in 1909 by dynamic vibration absorbers application with variable speed machines yuri khazanov, p. Therefore a tunable absorber was designed to be tuned in at the forced frequency. Several variable stiffness vibration absorbers have been proposed. The dynamic magnification factors for an undamped main system, i. An active dynamic vibration absorber for a handheld vibro. It is seen that the vibration of the main mass m is effectively suppressed for all excitation frequencies. Jul 10, 2019 the damped dynamic vibration absorbers. The dynamic vibration absorber cancels out resonant vibration.
The damping characteristics of the absorber are assumed stochastic. The use of dynamic vibration absorbers to control the vibration of a structure in both narrow and broadbands is discussed in this paper. The working principle of the dynamic vibration absorber, as shown in fig. Vibration measurements were taken at selected points under normal operational running speed conditions, and a dominant amplitude at first order running speed was observed in all the measured frequency domain signals.
This site is like a library, use search box in the widget to get ebook that you want. Dynamic vibration absorbers dva are based on the concept of attaching a secondary mass to a primary vibrating system such that the. Pdf the use of dynamic vibration absorbers to control the vibration of a structure in both narrow and broadbands is discussed in this paper. All seismic vibration control devices may be classified as passive, active or hybrid where. The absorber works as a subsystem attached to the target vibration damper, the reaction force generated by the subsystem in the resonance can reduce the vibration of the main system. In mechanical engineering a commonly used approach to attenuate vibration amplitudes in resonant conditions is the attachment of a dynamic vibration absorber. In order to let the amplitude of the primary system be zero, the design working frequency of the vibration absorber. In order to control the vibration of sheet metal parts, a passive dynamic vibration absorber is designed based on dynamic vibration absorption theory in this paper, and the performance of the vibration absorber is verified by. On the usage of dynamic vibration absorbers for reduction of forced vibrations of a system of coupled rigid bodies. Dynamic vibration absorber design for a motor and pump assembly. Optimum design of damped dynamic vibration absorber a. Article information, pdf download for optimization of damped. Vibration control of a plate subjected to impulsive force.
The tuning of the dynamic vibration absorber is the procedure that sets the antiresonance frequency to a given value by adjusting the parameters of the dynamic vibration absorber. Proceedings of the asme 2009 international design engineering technical conferences and computers and information in engineering conference. In the third part, analytical amplitudes of vibration are deter mined. To reduce the vibration of a primary device by adding an absorber to the system applications. This document is highly rated by mechanical engineering students and. Dynamic shock absorber a major qualifying project report submitted to the faculty of worcester polytechnic institute worcester, massachusetts, u. In the civil engineering field, vibration control devices are ever more required to face dynamic excitation such as wind load and ground motion. Dynamic vibration absorbers and vibration isolator lecture 19 nptel.
The added mass can be a block of metal or a ring, for example, mounted on rubber pads or metal flexures, and glued, strapped or press fit onto the base structure. This study aims to effectively and robustly suppress the lowfrequency vibrations of floating slab tracks fsts using dynamic vibration absorbers dvas. At first, the analytical solution of the system is obtained based on the established differential motion equation. Without the vibration absorber or tmd, the single degreeoffreedom system is in resonance. Vibration absorber an overview sciencedirect topics. Click download or read online button to get dynamics and vibration book now. Dynamic vibration absorbers application with variable speed. Analysis of parallel damped dynamic vibration absorbers. Temporary dynamic absorbers can usually be attached by bolting or with c clamps. Tuned mass dampers, consisting of a secondary mass, a viscous damper and an. The most common method of vibration control is the use of the dynamic absorbers. Lowfrequency vibration control of floating slab tracks using dynamic vibration absorbers.
Reciprocating machines building excited by an earthquake transmission lines or telephone lines excited by wind blowing. Dynamic vibration absorber is a kind of vibration reduction device, its basic structure includes the quality components, stiffness components and damping components. Three fixed points are found in the amplitudefrequency curves of the primary system. This paper describes the detailed design analysis of the absorber. As a benchmark problem, a plate incorporating multiple. Structures are often idealised as simple systems for the purpose of analysis. At resonance, the dva will cut vibration to lower levels. This rugged absorber is ideal for existing compressors, pumps or piping systems experiencing high vibration due to resonance. The same vibration absorber was used to study noncollocated adaptivepassive vibration control in ref. It consists of auxiliary system attached to the main system that needs to be protected from excessive. Reference 6 provides a survey of vibration isolation methods, ref.
These methods require the use of many translationaltype massspring absorbers for creating a region of nearly zero amplitude in the beam structure. Modeling and simulation technology of dynamic vibration. Dynamic absorber mechanical acousticsvibration engineering. A detailed and extensive description regarding the theory of passive dynamic absorbers not requiring additional energy sources. A typical result of dmf is shown in figure 3 for a. On the attachment location of dynamic vibration absorbers. The force generated by the mass b is 180 degrees outofphase with the exciting force.
Optimization of dynamic vibration absorbers placed on the tunnel interior surface to mitigate underground railwayinduced vibration behshad noori1, victor cubria2, robert arcos2, arnau clot2, jordi romeu2 1av ingenieros behshad. The unique feature behind the dva is that it has an extremely long life and will not fail due to excessive vibration. This paper examines modelling of the dynamics of a plate by plate type dynamics vibration absorber subjected to a localized periodic impulsive excitation. Simple vibration neutraliser ppt mechanical engineering notes edurev notes for mechanical engineering is made by best teachers who have written some of the best books of mechanical engineering. Application of a dynamic vibration absorber to a piecewise. Pdf dynamic vibration absorbers and its applications. With opposing forces acting on mass a, the vibration of system a is effectively reduced. Dynamic shock absorber worcester polytechnic institute. Highrise structures will experience alongwind vibration and acrosswind vibration or earthquake loads whereas bridges are subjected to traveling loads such as moving crowds. Herve sonfack bouna, blaise romeo nana nbendjo laboratory of modelling and simulation in engineering, biomimetics and prototype, faculty of sciences, university of yaounde i. Application of dynamic vibration absorbers in structural vibration. Dec 04, 2017 designing a dynamic vibration absorber for single spring mass system. The basics equations are solve numerically using fourth order runge kutta algorithm.
The dynamic absorber is by no means a new tool for controlling resonate vibration. Pdf dynamic vibration absorbers for vibration control within a. The second part of this paper deals with the derivation of the equations of motion of the main plate with hinged ends subjected to localized impulsive excitations. An important parameter when designing absorbers for multi degree of freedom systems is the location. Study of magnetic vibration absorber with permanent magnets. Dynamic vibration absorber, equalpeak method, optimization, frequency response curve, bilinear interpolation. A smart dynamic vibration absorber for suppressing the vibration of.
In the following table and figures the response of the general linear dynamic vibration absorber is developed for mass ratio n0. The vibration absorbers are frequently used to control and minimize excess vibration in structural system. In conjunction with the gas machinery research council, wood beta machinery analysis has developed the damped vibration absorber dva. Nonlinear magnetic vibration absorber for passive control of a. In earthquake engineering, vibration control is a set of technical means aimed to mitigate seismic impacts in building and nonbuilding structures.
Dynamic absorbers are widely found in automobiles, airplanes and skyscrapers. Analysis of parallel damped dynamic vibration absorbers journal. Designing a dynamic vibration absorber for single spring mass system. If the temporary dynamic absorber does effectively reduce the vibration, it can also be left in place to minimize the vibration until a more. An analytical solution of the modal equation is proposed and validated using direct numerical simulation of the basic equations.
Firstly, experimental modal analysis is conducted to determine the effects of the dynamic vibration absorber on the frequency response function of the modified cutting tool system. Optimization of damped dynamic vibration absorber to control. Integration of vibration absorbers in milling chucks asme. Performance of a non linear dynamic vibration absorbers. Pdf optimal design of a dynamic vibration absorber with. The basic principle of operation is vibration out of phase with the vibration of such structure, thereby applying a counteracting force. Optimization of design of one mass dynamic vibration. Application example for variable speed pump applications, a.
By analogy, holding one leg of a vibrating tuning fork also stops the vibration of the other leg. The mass and geometry of the vibration absorber are varied and its integration in the milling chuck is explored. The dynamic vibration absorber is a tuned springmass system, which reduces or eliminates the vibration of a harmonically excited system. The design formulae for the optimum tuning ratio and optimum stiffness ratio of dva are obtained by. The displacement amplitudes at the center point are minimized in a frequency range 0, 120 hz fig. The use of linear absorbers allows reducing vibration but only at the resonance frequency, whereas nonlinear absorbers attenuate vibration on a wide band of frequency. A new type of dynamic vibration absorber dva with negative stiffness is studied in detail.
Use of active element for example, a hydraulic actuator would increase the advantage of tuned mass damping for a broad frequency range. Study of magnetic vibration absorber with permanent. Vibration control of a plate subjected to impulsive force by. Dynamic absorbers reduce vibration cutting tool engineering.