Acoustic Emission by Quartz Tuning Forks and Other Oscillating Structures in Cryogenic 4He Fluids
- 270 Downloads
We report on experimental investigations of acoustic emission by quartz tuning forks resonating at frequencies 32 kHz, 38 kHz, 77 kHz and 100 kHz immersed in cold gaseous 4He and its normal and superfluid liquid phases. Frequency dependence of the observed low-drive-linewidth at 350 mK together with the temperature and pressure dependences (1.3 K < T < 4.2 K, 0 < p < 25 bar) of the observed damping of the high frequency (77 and 100 kHz) resonators measured in normal liquid 4He and its superfluid phase provide strong and direct evidence of the importance of sound emission by these tuning forks. Three analytical models of acoustic emission by vibrating tuning forks are developed and compared with the experimental results. We also discuss the importance of sound emission for experiments with the commonly used 32 kHz tuning forks as well as other oscillating structures—spheres, wires, grids and various micromachined sensors. We compare the relative importance of dissipative losses due to laminar viscous/ballistic drag and acoustic emission in liquid and superfluid 4He.
KeywordsQuartz tuning fork Cryogenic helium Acoustic emission
Unable to display preview. Download preview PDF.
- 2.K. Karrai, R.D. Grober, Tip-sample distance control for near-field scanning optical microscopes, in Near-Field Optics, ed. by M.A. Paesler, P.T. Moyer. Proc. SPIE, vol. 2535 (1995), p. 69 Google Scholar
- 8.M. Blažková, D. Schmoranzer, L. Skrbek, J. Low Temp. Phys. 34, 380 (2008) Google Scholar
- 20.D. Garg, V.B. Efimov, M. Giltrow, P.V.E. McClintock, L. Skrbek, W.F. Vinen, Mutual interactions between oscillating objects in superfluid 4He: critical velocities and the persistence of remanent vortices, Europhys. Lett. (submitted) Google Scholar
- 21.L.D. Landau, E.M. Lifshitz, Hydrodynamics, 2nd edn. (Pergamon Press, New York, 1987) Google Scholar
- 27.I.M. Khalatnikov, Theory of Superfluidity (Nauka, Moscow, 1971) (in Russian) Google Scholar
- 28.S.P. Timoshenko, D.H. Young, Theory of Structures, 2nd edn. (McGraw-Hill College, New York, 1965) Google Scholar
- 29.M. Abramovitz, I.A. Stegun, Handbook of Mathematical Functions. Applied Mathematics Series, vol. 55 (National Bureau of Standards, Washington, 1964) Google Scholar
- 30.P.M. Morse, K.U. Ingard, Theoretical Acoustics (Princeton University Press, Princeton, 1986) Google Scholar
- 31.R.D. McCarty, Thermophysical properties of Helium-4 from 2 to 1500 K with pressures to 1000 atmospheres, Technical Note 631 National Bureau of Standards (1972) Google Scholar
- 32.V.D. Arp, R.D. McCarty, The properties of critical helium gas, Tech. Rep., U. of Oregon (1998) Google Scholar
- 34.L. Skrbek, W.F. Vinen, The use of vibrating structures in the study of quantum turbulence, in Progress in Low Temperature Physics, ed. by M. Tsubota, W.P. Halperin, vol. XVI (Elsevier, Amsterdam, 2009), Chap. 4 Google Scholar