Abstract
Experiments have been carried out to investigate the effects of aging on the frequency response of a fine cold-wire located in a flow seeded with oil particles used for laser Doppler anemometry. Transfer functions are shown to depend strongly on the running time. Photo-micrographs show that the contamination effect is due to discrete droplets, the diameter of which increases with running time. Reduction of frequency response is shown to affect at first the high-frequency range and then an intermediate range of frequencies that are larger than the inverse of the oil droplets time constant. Good agreement is found between experimental results and predictions derived from a simple model of the contaminated wire. This contamination process requires testing and cleaning the wire steadily in order to keep a significant frequency response and, if needed, to correct temperature fluctuations.
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Abbreviations
- a :
-
Thermal diffusivity (m2 s−1)
- c :
-
Thermal capacity (J kg−1 K−1)
- d :
-
Wire diameter (m)
- dB :
-
Decibel attenuation
- dZ :
-
Fourier–Stieltjes temperature component, K
- D G :
-
Droplet diameter (m)
- H(n):
-
Transfer function
- l :
-
Length (m)
- M :
-
Time constant (s)
- n :
-
Frequency (Hz)
- N :
-
Number of droplets
- Nu:
-
Nusselt number
- Pr:
-
Prandtl number
- Re:
-
Reynolds number
- t :
-
Time (s)
- T :
-
Temperature (K)
- λ:
-
Thermal conductivity (W m−1 K−1)
- ρ:
-
Density (kg m−3)
- c:
-
Conduction
- e:
-
Elementary
- g:
-
Fluid
- G:
-
Droplet
- 0:
-
Prong
- p:
-
Plateau
- w:
-
Wire
References
Attoui M, Ren KF, Girasole T, Garo A, Gouesbet G, Grehan G (1999) Détermination de la granulométrie et de la concentration d’un aérosol submicronique par mesure du coefficient d’extinction à plusieurs longueurs d’onde. 15e Congrès Français sur les Aérosols, Paris 8–9 décembre
Bruun HH (1995) Hot-wire anemometry, Oxford Science Publications. Oxford 7:231–233
Freymuth P (1979) Engineering estimates of heat conduction loss in constant temperature thermal sensors. TSI Quaterly 5:3–9
Fulachier L (1978) Hot wires measurements in low speed heated flows. Proceedings of the Dynamic Flow Conference, Marseille
Heist DK, Castro IP (1998) Combined laser-Doppler and cold wire anemometry for turbulent heat flux measurement. Experiments in Fluids 24:375–381
La Rue JC, Deaton T, Gibson CH (1975) Measurement of high frequency turbulent temperature. Rev Sci Instr 46:757–764
Lecordier J-C, Petit C, Paranthoën P (1981) Influence de la conduction sur la fonction de transfert des fils froids dans les très basses fréquences. Lett Heat Mass Trans 8:103–114
Lecordier J-C, Dupont A, Gajan P, Paranthoën P (1984) Correction of temperature fluctuation measurements using cold wires. J Phys E 17:307–311
Paranthoën P, Lecordier J-C, Petit C (1982) Influence of dust contamination on frequency response of wire resistance thermometers. DISA Info 27:36–37
Perry AE, Smits AJ, Chong MS (1979) The effect of certain low frequency phenomena on the calibration of hot-wires. J Fluid Mech 90:415–439
Pietri L, Amielh M, Anselmet F (2000) Simultaneous measurements of temperature and velocity fluctuations in a slightly heated jet combining a cold wire and laser Doppler anemometry. Int J Heat Fluid Flow 21:22–36
Schacher G, Fairall CW (1976.) Use of resistance wires for turbulence measurements in marine environment. Rev Sci Instr 47:703–707
Smits AJ, Perry AE, Hoffmann PJ (1978) The response of temperature fluctuations of constant current hot-wire anemometer. J Phys E 11:909–914
Steyer A, Guenoun P, Beysens D, Fritter D, Knobler CM (1990) Growth of droplets on 1D surface: experiment and simulation. Europhysics Lett 12:211–215
Thole KA, Bogard DG (1993) Simultaneous temperature and velocity measurements. Meas Sci Technol 5:435–439
Weiss F (1999) Etude expérimentale de la diffusion de la chaleur en aval d’une source linéaire placée dans une allée de Bénard-von Karman. Thèse Université de Rouen
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Weiss, F., Paranthoën, P. & Lecordier, JC. Frequency response of a cold-wire in a flow seeded with oil particles. Exp Fluids 39, 935–940 (2005). https://doi.org/10.1007/s00348-005-0032-6
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DOI: https://doi.org/10.1007/s00348-005-0032-6