Abstract This article aims to study the mass transient diffusion in solids with a cylindrical shape. To this end, one-dimensional equation was discretized using finite volume method fully implicit formulation. The solution can be used simulate diffusive processes and determine thermophysical parameters via optimization techniques. computational package developed applied thin-layer drying of peeled bananas. Three models were describe process: (1) V effective diffusivity D are considered...

Summary To describe water transport in a porous media, mathematical model is usually used. Among the models available literature, empirical and diffusive ones can be cited. In this paper, P age diffusion are used to drying soaking of chickpea. addition, new equation proposed mentioned processes. According results, two well soaking, but one gives best statistical indicators. The use process makes it possible determine effective diffusivities (7.13 × 10 −11 , 10.39 13.78 m 2 s −1 for air at...

In the present work, drying of jackfruit seeds (with and without endocarp) was carried out in an oven at temperatures 60 70°C. The objective this work is to apply two diffusive models describe use them analyze effects temperature endocarp presence on thermo-physical parameters process. For this, numerical solutions were developed considering shrinkage diffusivity as a function local moisture content. applied study obtained follows: variation (model 1); constant disregarding 2). According...

The use of waste has been the focus attention agri-food sector, and a fruit with large amount is passion fruit. Its peel consists albedo flavedo, which can be used to manufacture flour, some studies propose need remove flavedo as well perform maceration. objective present work was study drying process produce flour from whole peel, checking influences removal maceration steps, temperatures (70 80 ºC). Yield after calculated it shown low. Page, Silva et alii, Henderson Pabis...

Abstract The objective of this work was to apply a diffusive model describe the drying melon peels and use them analyze process for various operating conditions. For this, numerical solution developed considering shrinkage diffusivity as function local moisture content. This obtained boundary condition third kind. In present work, carried out in an oven (with without osmotic pretreatment) at temperatures 60 70°C. pretreatments were binary solutions (sucrose distilled water) with 20 °Brix...

This work presents a three-dimensional numerical solution for the diffusion equation in transient state, an arbitrary domain. For this end, was discretized using finite volume method with fully implicit formulation and generalized coordinates, equilibrium boundary condition. each time step, system of equations obtained given structured mesh solved by Gauss-Seidel method. The computational code developed FORTRAN, CFV 6.6.0 Studio, Windows platform. proposed validated analytical solutions...

In this article, a methodology is used for the simultaneous determination of effective diffusivity and convective mass transfer coefficient in porous solids, which can be considered as an infinite cylinder during drying. Two models are optimization drying simulation: model 1 (constant volume diffusivity, with equilibrium boundary condition), 2 condition). Optimization algorithms based on inverse method were coupled to analytical solutions, these solutions adjusted experimental data kinetics....

Abstract In this paper, the influence of geometric representation samples a composite material on description its water absorption is studied. It supposed that diffusion models with boundary condition first kind satisfactorily describe absorption, and volume effective mass diffusivity are constant during process. The geometries used to represent are: infinite slab, rectangular plate parallelepiped. determined by coupling analytical solution corresponding model an optimizer based inverse...

This chapter presents an analytical modeling of mass transfer in wet porous bodies during the continuous and intermittent drying process fixed bed. The was simulated assuming liquid diffusion as only transport mechanism constant coefficient. presented models involve spherical, cylindrical prolatespheroidalgeometries. Simulation tests ellipsoidal solids were performed results compared with curve order to evaluate tempering effect optimization. It possible simulate moisture distribution...

Mass transfer in clay slabs during drying is described using diffusion models with equilibrium (model 1) and convective 2) boundary conditions. Drying experiments hot air were performed for initial moisture content of 0.11 (dry basis, db) at 50, 60, 70, 80 90 °C. For this content, occurred falling rate. the slabs, one-dimensional solutions referring to 1 2 coupled optimizers determine process parameters each temperature. Thus, equations can be obtained express these as a function The...

O objetivo deste trabalho foi estudar o transporte de água, através do modelo da difusão líquida, em placas cerâmicas que podem ser usadas como revestimento alvenaria, bem apresentar um algoritmo otimização baseado no método inverso. Para atingir os objetivos apresentado acoplado à solução analítica equação difusão, possibilitando determinar parâmetros processo a partir dos dados experimentais secagem das placas. A condição contorno empregada terceiro tipo e geometria considerada...

In this study, mass transfer simulations were performed during the process of osmotic dehydration green beans in NaCl solutions 20 and 26.5% at 50 °C. Additionally, effect solute concentration on boundary conditions was investigated. For such, a diffusion model – assuming constant diffusivity geometry an infinite cylinder considered. A numerical solution also developed coupled with optimizer order to obtain parameters using experimental data. The results consistent those mentioned...

En Curacavi, Chile (33°25?S; 72°11?W), se establecieron cuatro cultivares de esparrago (Asparagus officinalis), tres hibridos (Atlas, JWC- 1, y UC-157 F1) un cultivar obtenido por polinizacion libre del F2, en poblaciones 22.222, 33.333, 44.444 55.555 plantas·ha-1, con el objetivo determinar efecto las sobre comportamiento productivo los cultivares. Los resultados temporadas cosecha indicaron una produccion creciente a traves que al aumentar la poblacion rendimientos incrementan...

In this work, a numerical solution for the diffusion equation applied to solids with arbitrary shape considering convective boundary condition is presented. To end, equation, written in generalized coordinates, was discretized by finite-volume method fully implicit formulation. The transport parameters and dimensions of are considered constant during all process. For each time step, system equations obtained given non-orthogonal structured mesh solved Gauss-Seidel method. One computational...