Study of the measurement for the diffusion coefficient by digital holographic interferometry

Abstract

In the measurement of the diffusion coefficient by digital holographic interferometry, the conformity between the experiment and the ideal physical model is lacking analysis. Two data processing methods are put forward to overcome this problem. By these methods, it is found that there is obvious asymmetry in the experiment and the asymmetry is becoming smaller with time. Besides, the initial time for diffusion cannot be treated as a constant throughout the whole experiment. This means that there is a difference between the experiment and the physical model. With these methods, the diffusion coefficient of KCl in water at 0.33 mol/L and 25°C is measured. When the asymmetry is ignored, the result is 1.839×10(-9) m2/s, which is in good agreement with the data in the literature. Because the asymmetry is becoming smaller with time, the experimental data in the latter time period conforms to the ideal physical model. With this idea, a more accurate diffusion coefficient is 2.003×10(-9) m2/s, which is about 10% larger than the data in the literature.

Interferometric Probing of Physical and Chemical Properties of Solutions: Noncontact Investigation of Liquids

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Development of optical digital interferometry for visualizing and modelling the mass diffusion of ammonia in water in an absorption process

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Experimental study of the solubility and diffusivity of CO2 and O2 in RP-3 jet fuel

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