Effect of Radial Confinement on Wave Propagation and Vibrational Response in Bars
It is currently beyond the state-of-the art to accurately predict the instantaneous dynamic response of a structure with rapidly changing boundary conditions. In order to establish a basic understanding of changing boundary conditions, we examine the wave propagation through a bar subject to mechanical confinement. The Air Force Research Laboratory has conducted several experiments investigating the effect of non-traditional boundary conditions, such as mid-structure confinement, on the local and global dynamic response of rods using a modified Hopkinson Bar configuration with radial clamping. We have shown that the wave velocity in the mechanically clamped area is significantly lower than that in a stress free bar. This paper presents the experimental results and analytical modeling of the effect of radial confinement on dynamic response in bars.
KeywordsWave propagation Confined effects Hopkinson bar Dispersion Experimental mechanics
The authors would like to thank AFOSR (Program Manager: Dr. David Stargel) and the Air Force Research Laboratory for supporting this research effort. Opinions, interpretations, conclusions, and recommendations are those of the authors and are not necessarily endorsed by the United States Air Force.
- 1.Pochhammer L (1876) On the propagation velocities of small oscillations in an unlimited isotropic circular cylinder. J fur die Reine Angew Mathematik 81:324–326Google Scholar
- 2.Chree C (1889) The equations of an isotropic elastic solid in polar and cylindrical coordinates, their solutions and applications. Trans Camb Philos Soc 14:250–369Google Scholar
- 3.Kolsky H (1963) Stress waves in solid. Clarendon Press, OxfordGoogle Scholar
- 5.2001, Kulite Strain Gage Manual, Kulite Semiconductor ProductsGoogle Scholar
- 6.Prescale Pressure Sensitive Film, 6 Oct 2014, http://www.fujifilm.com/products/prescale/prescalefilm/
- 7.2009, Precision 28144 quad-channel wideband transducer conditioner with voltage and current excitation (datasheet). Precision Filters, IthacaGoogle Scholar
- 8.2003, NI PXI-6133 Specifications, National Instruments, AustinGoogle Scholar
- 11.Van Zandt T (2006) Development of efficient reduced models for multi-body dynamics simulations of helicopter wing missile configurations. Master’s thesis, University of Massachusetts LowellGoogle Scholar