Damping and layer configuration in wood veneer composites

Mueller, C.; Mayer, Tobias A.; Eichhorn, Sven

doi:10.1007/s10086-011-1206-x

Cited by 3 publications

(1 citation statement)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition, nonmetals show an amplitude dependency, too. Studies on ceramics, 29 wood, 30 and different polymers such as polystyrene, 31 vinyl, 32 rubber, 33 and, less significantly, fiber-reinforced plastics 23 are known.…”

Section: Introductionmentioning

confidence: 99%

Metal–plastic composites with amplitude-dependent constraint layer damping

Klaerner

Wuehrl

Kroll

et al. 2019

Proceedings of the Institution of Mechanical Engineers, Part C:

View full text Add to dashboard Cite

For metal–plastic composites with thin shear-sensitive cores, high damping can be determined. These materials were developed to reduce the structure-borne noise and are therefore used for thin-walled components with bending loads. In addition to the known sensitivity due to the temperature and frequency, these materials show a significant dependency on vibration amplitudes. Within the framework of this study, the nonlinear damping of metal–plastic composites was determined experimentally using free-vibrating cantilever beams. A detailed analysis of the derived velocity–time curves showed a nonlinear damping within the decay. An exponential approach was successfully used to describe the relation between damping and current deflection. Furthermore, a strain energy-based evaluation is introduced to quantify the share of the core contributions. For this purpose, the strain energy of several acoustically sensitive car components as well as the beams with varying supports and vibration lengths were determined numerically with a finite element analysis. The strain energy ratio of the cores was then derived as a comparative measurement and within a finite element-based design of experiments. A cantilever beam setup with a component-specific beam length representing similar core strain energy ratios was retested and showed a similar exponential amplitude dependence but higher damping parameters.

show abstract

Section: Introductionmentioning

confidence: 99%

Metal–plastic composites with amplitude-dependent constraint layer damping

Klaerner

Wuehrl

Kroll

et al. 2019

Proceedings of the Institution of Mechanical Engineers, Part C:

View full text Add to dashboard Cite

show abstract

Amplitude-Dependent Damping: Experimental Determination and Functional Interpretation for Metal–Plastic Composites

Klaerner

Wuehrl

Kroll

et al. 2019

Int. J. Str. Stab. Dyn.

View full text Add to dashboard Cite

Composite materials offer a high freedom of design with regard to stiffness, strength and damping. In contrast to efficient anisotropic but linear material models, these composites often tend to react nonlinearly. Commonly, such nonlinear material damping models imply frequency and temperature dependency. In addition, some materials show a substantial amplitude sensitivity of the damping. Within this study, metal–plastic composites with highly dissipating shear sensitive cores have been used to experimentally determine the damping values with varying amplitudes. The results show a significance of this parameter already for small deflection within the geometrically linear range. The derived nonlinearity is further described by an exponential approach and parametrized by a regression analysis. Furthermore, the amplitude sensitivity is retraced to the contributions of the layered material by a detailed numerical analysis of the stress states. Therefrom, the mean strain energy density per material is derived as an amplitude criterion for the nonlinear damping model. The resulting model can be further applied to the finite element analysis to improve the determination of vibrations as well as structure borne sound of such acoustically improved materials.

show abstract

Surface roughness discrimination with the long cane: Effects of cane tips, handle, shaft rigidity, and swinging speed

Kim,

Wall Emerson,

Naghshineh

2023

British Journal of Visual Impairment

View full text Add to dashboard Cite

This study examined the effects of cane tip type, cane tip size, cane shaft rigidity, cane handle material, and cane swing speed on the cane user’s ability to discriminate surfaces of different roughness. A repeated-measures design with block randomization was used for each of the three studies. Blindfolded sighted and visually impaired participants attempted to identify which of the two grooved aluminum plates was rougher by swiping the plates using different cane tips, shafts, handles, and swing speeds. Participants correctly identified the rougher plate at a higher percentage with smaller cane tips (77.6% ± 8.7%) than with larger cane tips (72.1% ± 7.2%), p = .029, r = .54. Pencil tips (76.9% ± 8.4%) were more advantageous than ball tips (72.8% ± 6.5%), p = .028, r = .55. Slower cane swing speed (84.4% ± 2.6%) also allowed the participants to better discriminate the surfaces than faster swing speed (76.6% ± 6.0%), p = .002, r = .80. However, the cane shaft rigidity ( p = .499, r = .22) and cane handle material ( p = .694. w2 = 0.02) did not have a significant effect on the cane user’s ability to discriminate the surfaces of different roughness. Given these findings, a cane user may want to use a smaller and/or cylindrical cane tip as opposed to larger and/or spherical cane tip for better surface texture change detection. In addition, a cane user may not want to swing the cane too wide or walk too fast since wider cane swing and faster walking speed tend to result in faster cane swing speed, which can compromise one’s ability to detect sudden changes in walking surface texture. That being said, an Orientation and Mobility (O&M) specialist should assess each person’s traveling environment when determining which cane tip and swing speed to use in a given situation.

show abstract

Damping and layer configuration in wood veneer composites

Cited by 3 publications

References 2 publications

Metal–plastic composites with amplitude-dependent constraint layer damping

Metal–plastic composites with amplitude-dependent constraint layer damping

Amplitude-Dependent Damping: Experimental Determination and Functional Interpretation for Metal–Plastic Composites

Surface roughness discrimination with the long cane: Effects of cane tips, handle, shaft rigidity, and swinging speed

Contact Info

Product

Resources

About