| Autor: |
Mehta, J. M., Black, W. Z. |
| Zdroj: |
Applied Optics; June 1977, Vol. 16 Issue: 6 p1720-1726, 7p |
| Abstrakt: |
Errors caused by refraction and end effects in interferometric systems are studied analytically. Both errors are estimated for Mach-Zehnder and differential interferometers when these instruments were used to measure convective heat transfer coefficients in air and water. Both errors were found to be larger for the Mach-Zehnder interferometer than for the differential interferometer. This result suggests that the differential interferometer is potentially a more suitable and accurate device than the Mach-Zehnder interferometer, if one wishes to measure heat transfer coefficients. Convective heat transfer coefficients measured with a differential interferometer are presented. The experimental study used a specially designed test section, which was inserted into the interferometer. The test involved heat dissipated from a vertical plate by free convection to water. The measured results were found to compare satisfactorily with published results at Rayleigh numbers less than 10^4. At higher Rayleigh numbers, refraction caused sufficient bending of the light rays that a zone of no information next to the heated surface resulted in significant errors. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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