Draft:Friction-induced noises
Friction-induced noises, sometimes called soft sounds (in contrast to sharp sounds) are sounds produced by a variety of physical mechanisms, including both biological and mechanical sources, characterized by relatively gentle onset, sustained or gradually changing acoustic energy, and the absence of sudden, forceful impacts. They commonly arise from friction, steady vibration, the movement of fluids, or the gradual deformation of materials. Such sounds include creaks, squeaks, squeals, hums, buzzes, hisses, and rustles.
Soft sounds result from friction between solid surfaces. A common mechanism is the stick–slip phenomenon, a type of motion exhibited by objects in contact sliding over one another.
Terms
[edit]There are numerous words in the English language delineating particular varieties of soft sounds. Although these terms have no universally accepted scientific definitions, they generally reference recognizable acoustic characteristics.
- Buzz: a rapidly fluctuating sound produced by repeated vibration.
- Creak: a relatively low-pitched sound produced by stressed materials, particularly wood, leather, or metal joints.
- Hiss: broadband noise generated by turbulent airflow or escaping gas, also associated with animal threat postures, particularly with snakes and other reptiles.
- Hum: a steady low-frequency sound produced by vibration.
- Rustle: a sound associated with flexible materials rubbing together, often under the influence of the wind, such as leaves, paper, or fabric.
- Squawk: a harsher and louder high-pitched sound, most commonly produced by birds, particularly parrots and other large avian species, but also sometimes used to describe similar sounds produced by electronic devices, machinery, or people.
- Squeak: a short, relatively high-pitched friction sound, also associated with small animals.
- Squeal: a loud, sustained, high-pitched friction sound, often associated with brakes, tires, or slipping belts, or with animals in distress or a state of excitement.
- Whine: a continuous high-pitched mechanical or aerodynamic sound.
"First, a simple classification of automotive-friction induced noises is proposed and highlights three noise categories: squeal, squeak and creak noises".[1]
"creak is caused by a stick–slip phenomenon, squeal is mainly due to a mode-coupling phenomenon, while squeak can be caused either by mode-coupling or stick–slip phenomena".[1]
Friction-related dynamical instabilities are thought to be responsible for brake squeal and the 'song' of a glass harp,[2][3] phenomena which involve stick and slip, modelled as a drop of friction coefficient with velocity.[4]
The physical mechanisms for the incidental or unintended creations of the sounds can be intentionally harnessed for their generation from musical instruments, or as sound effects.
References
[edit]- 1 2 Elmaian, A.; Gautier, F.; Pezerat, C.; Duffal, J.-M. (February 1, 2014). "How can automotive friction-induced noises be related to physical mechanisms?". Applied Acoustics. 76. doi:10.1016/j.apacou.
- ↑ Flint, J.; Hultén, Johan (2002). "Lining-deformation-induced modal coupling as squeal generator in a distributed parameter disk brake model". Journal of Sound and Vibration. 254 (1): 1–21. Bibcode:2002JSV...254....1F. doi:10.1006/jsvi.2001.4052.
- ↑ Kröger, Matthias; Neubauer, Marcus; Popp, Karl (2008). "Experimental investigation on the avoidance of self-excited vibrations". Phil. Trans. R. Soc. A. 366 (1866): 785–810. Bibcode:2008RSPTA.366..785K. doi:10.1098/rsta.2007.2127. PMID 17947204. S2CID 16395796.
- ↑ Rice, J. R.; Ruina, A. L. (1983). "Stability of Steady Frictional Slipping" (PDF). Journal of Applied Mechanics. 50 (2): 343–349. Bibcode:1983JAM....50..343R. CiteSeerX 10.1.1.161.5207. doi:10.1115/1.3167042. Archived (PDF) from the original on 2010-06-22.
{{cite journal}}: Cite uses deprecated parameter|citeseerx=(help)