A comparison of concentration measurement techniques for the estimation of the apparent mass diffusion coefficient

• Main Authors: L.M. Pereira, R. De Souza, H.R.B. Orlande, R.M. Cotta
• Format: Article
• Language: English
• Published: Brazilian Society of Chemical Engineering 2001-09-01
• Series: Brazilian Journal of Chemical Engineering
• Subjects: radiation measurement technique; electrical conductivity measurement technique
• Online Access: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0104-66322001000300005

In this article we compare two different techniques to measure the concentration of saline solutions for the identification of the apparent mass diffusion coefficient in soils saturated with distilled water. They are the radiation measurement technique and the electrical conductivity measurement technique. These techniques are compared in terms of measured quantities, sensitivity coefficients with respect to unknown parameters and the determinant of the information matrix. The apparent mass diffusion coefficient is estimated by utilizing simulated measurements containing random errors. The Levenberg-Marquardt method of minimization of the least-squares norm is used as the parameter estimation procedure. The effects of the volume of saline solution injected into the column devised for the experiments on the accuracy of the estimated parameters are also addressed in this article.