ISSN 0976 – 6340 (Print) ISSN 0976 – 6359 (Online) Volume 3, Issue 3, Septmebr - December (2012), pp. 214-228 © IAEME: www.iaeme.com/ijmet.html Journal Impact Factor (2012): 3.8071 (Calculated by GISI) www.jifactor.com

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DESIGN AND DEVELOPMENT OF A PENDULUM TYPE DYNAMIC VIBRATION ABSORBER FOR A SDOF VIBRATING SYSTEM SUBJECTED TO BASE EXCITATION Irshad M. Momin1, Dr. Ranjit G. Todkar2 1 Assistant Professor, Department of Textile Engineering, DKTE’s Textile & Engineering Institute, Ichalkaranji, Maharashtra, India. E mail: irshad_momin2000@yahoo.co.in 2 Professor, Department of Mechanical Engineering, Annasaheb Dange College of Engineering and Technology, Ashta, Maharashtra, India. E mail: rgtodkar@gmail.com ABSTRACT The use of centrifugal pendulum for dynamic vibration absorber design (CPVAs) is a proven method for reducing undesired torsional vibrations in rotating systems. These devices are in use for many years, most commonly in light aircraft engines, helicopter blade rotors etc. These devices have also been reported for reduction of rectilinear vibrations. Pendulum type dynamic vibration absorbers use impact forces for effective reduction of rectilinear vibrations describing modeling method and transient state analysis in view of spring impact absorbers, floating impact absorbers and pendulum impact absorbers. Bond graph technique for modeling of SDOF vibrating system excited by rotation unbalance at the sprung mass using a pendulum type dynamic vibration absorber is reported in the recent literature. This paper deals with the modeling and design procedure for a centrifugal pendulum type dynamic vibration absorber (CPVA) subjected to base excitation. This paper presents a detailed analysis and experimental investigations of the effect of parameters affecting the motion transmissibility of the sprung mass such as size of the pendulum mass, eccentricity of the pendulum pivot with respect to axis of rotation of the pendulum assembly, mass ratio (ratio of the pendulum mass to the sprung mass), gear ratio (the ratio of the pendulum rotational frequency to the excitation frequency) and the frequency ratio (the ratio of the excitation frequency to the natural frequency of the SDOF system). It has been proved that the CPVA is effective in reduction of motion transmissibility of the sprung mass of the SDOF system with the proper selection of the affecting parameters. Keywords: Centrifugal Pendulum Vibration Absorber (CPVA), Motion transmissibility, SDOF, Mass ratio, Gear ratio, Frequency ratio.

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International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 – 6340(Print), ISSN 0976 – 6359(Online) Volume 3, Issue 3, Sep- Dec (2012) © IAEME

1. INTRODUCTION The use of centrifugal pendulum for dynamic vibration absorber design (CPVAs) is a proven method for reducing undesired torsional vibrations in rotating systems. These devices are in use for many years most commonly in light aircraft engines, helicopter blade rotors [1]. Vibration suppression of helicopter blade assembly is extremely important as it is principal cause of the entire system vibration leading to harmful effects to the machinery and the passengers. In this case the blade vibrating system can be modeled as a 2DOF as well as 3DOF vibrating system consisting of a rigid blade and a pendulum type dynamic vibration absorber system based on non-linear dynamics [2]. Pendulum type dynamic vibration absorbers have also been reported using impact forces for effective reduction of rectilinear vibrations describing modeling method and transient state analysis in view of spring impact absorbers, floating impact absorbers and pendulum impact absorbers [3]. These absorbers continue to find new...