Application of inverse concepts to drying

Abstract

This paper deals with the application of inverse approaches to estimation of drying body parameters. Simultaneous estimation of the thermo physical properties of a drying body as well as the heat and mass transfer coefficients, by using only temperature measurements, is analyzed. A mathematical model of the drying process has been developed, where the moisture content and temperature fields in the drying body are expressed by a system of two coupled partial differential equations. For the estimation of the unknown parameters, the transient readings of a single temperature sensor located in an infinite flat plate, exposed to convective drying, have been used. The Levenberg-Marquardt method and a hybrid optimization method of minimization of the least-squares norm are used to solve the present parameter estimation problem. An analysis of the influence of the drying air velocity, drying air temperature, drying body dimension, and drying time on the thermophysical properties estimation, that enables the design of the proper experiments by using the so-called D-optimum criterion was conducted. In order to perform this analysis, the sensitivity coefficients and the sensitivity matrix determinant were calculated for the characteristic drying regimes and the drying body dimensions.

Mass transfer during the osmotic dehydration of West Indian cherry

“…Among the deterministic methods, the LevenbergeMarquardt method has been used successfully in several areas (Kanevce, Kanevce, & Dulikravich, 2005;Mejias, Orlande, & Özisik, 2003;Mendonça, Filho, & Silva, 2005). Among the stochastic methods, the Differential Evolution method has been applied less frequently to inverse problems, but has been used by Kanevce et al (2005); Mariani and Coelho (2009a); Mariani and Coelho (2009b); Mariani, Lima, and Coelho (2008); da Silva, da Silva, and Mariani (2009).…”

Study of heat and mass transfer control inside channel partially filled with a porous medium using nanofluids

“…The average density of this phase is not constant; the mass conservation equation of the gas phase is given by: (6)  Vapour phase (7) o The average velocities of the nanofluid phase and the gas phase are obtained using Darcy's law:  Nanofluid phase (8) -Gas phase (9) o Energy conservation equation (10) is the latent heat of vaporization at temperature T (K):…”

“…Fluid flow and heat transfer in porous media has been the subject of several investigations in the recent years [1][2][3][4][5] due to its wide applications in engineering fields such as heat exchangers, geothermal energy, oil recovery, solar collectors, building construction and especially drying processes [6][7]. Consequently, the high-energy consumption during drying of porous solids has made it a subject of scientific and technological interest in a great number of industrial applications, including food, wood [8], paper, textile, ceramics, building materials, steel Balls [9] and brick which is the subject of our study.…”

Retrieving of the initial moisture field in porous material based on temperature measurements during drying

“…For instance, in the literature numerous works by Kanevce, Kanevce and Dulikravich can be found. Kanevce et al [6,7] considered inverse concepts to 1D Luikov diffusion transient problem of drying the thin body. Additionally, in [7] they took into account the shrinkage effect.…”