Affiliations: School of Electrical \& Electronic Engineering,
Singapore | School of Mechanical and Production Engineering,
Nanyang Technological University, Nanyang Avenue, Singapore 639798,
Singapore | Department of Civil Engineering, National University
of Singapore, Singapore 117602, Singapore | DSO National Laboratory, 20 Science Park Drive,
Singapore 118230, Singapore
Abstract: The technique of a bean bag damper has been effectively applied in
many engineering fields to control the vibroimpact of a structural system. In
this study, the basic parameters responsible for the design of an effective
bean bag: the size of beans, the mass ratio of the bean bag to the structure to
which it is attached, the clearance distance and the position of the bag, are
studied by both theoretical and experimental analyses. These will provide a
better understanding of the performance of the bean bag for optimisation of
damper design. It was found that reducing the size of beans would increase the
exchange of momentum in the system due to the increase in the effective contact
areas. Within the range of mass ratios studied, the damping performance of the
damper was found to improve with higher mass ratios. There was an optimum
clearance for any specific damper whereby the maximum attenuation could be
achieved. The position of the bag with respect to nodes and antipodes of the
primary structure determined the magnitude of attenuation attainable.
Furthermore, the limitations of bean bags have been identified and a general
criteria for the design of a bean bag damper has been formulated based on the
study undertaken. It was shown that an appropriately configured bean bag damper
was capable of reducing the amplitude of vibration by 80% to 90%.
Keywords: bean bag, vibroimpact, shock, vibration and impact damper
