Two-Dimensional Mathematical Modeling of Heat and Mass Transfer in Fluidized-Bed Drying of Porous Material

A two-dimensional mathematical model of simultaneous heat and mass transfer for porous media drying was derived based on the Whitaker’s theory in the present study. The cylindrical coordinate system, which is more practical than the spherical one, was adopted. The model was solved numerically under the circumstance of fluidized-bed drying. The control-volume method with the fully implicit scheme was applied for discretization of governing equations. Physical properties of apple were selected in the simulation. Under typical operating conditions, heat and mass transfer mechanisms were analyzed based on the profiles of temperature and saturation inside the particles. Effects of the temperature, humidity and inlet velocity of hot gas were examined under different operating conditions. Simulation results show that the drying process can be significantly affected by coupled heat and mass transfer between gas and solid phases. The drying time increases with the increase in temperature and velocity of inlet hot gas, and decreases with the increase in humidity and bed area factor.

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A Short Review on Fluidized Bed Dryer

Asian Journal of Pharmaceutical Research ◽

10.52711/2231-5691.2021.00020 ◽

2021 ◽

pp. 104-105

Author(s):

Akash H. Mali ◽

Aditya R. Nikam ◽

Azam Z. Shaikh.

Keyword(s):

Mass Transfer ◽

Heat And Mass Transfer ◽

Fluidized Bed ◽

Short Review ◽

High Heat ◽

Drying Process ◽

Drying Time ◽

Fluidized Bed Dryer ◽

Advantages And Disadvantages ◽

Fluidized Bed Drying

This artical also discusses about demostration of fluidized bed dryer with principle and application and other processing. This has lead to development of thechnology, process and equipments which not only reduce time but also increasing the output. A Fluidized bed dryer significantely reduce drying time, compared with vaccum dryer or tray dryer. In the pharmacutical industry, fluidized bed dryer are typically used for pellets drying, coating and granulation. Fluidized bed drying are very well known to yield high heat and mass transfer and hence adopted to many industrial drying process particularly pharmacy product. In this paper we show construction, working of the fluidized bed dryer. It work on the drying principle. It has several advantages and disadvantages.

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MATHEMATICAL MODELLING OF SIMULTANEOUS HEAT AND MASS TRANSFER IN FLUIDIZED BED DRYING OF LARGE PARTICLES

Transactions of the Canadian Society for Mechanical Engineering ◽

10.1139/tcsme-1999-0009 ◽

1999 ◽

Vol 23 (1B) ◽

pp. 129-145 ◽

Cited By ~ 1

Author(s):

E. Hajidavaloo ◽

F. Hamdullahpur

Keyword(s):

Mass Transfer ◽

Partial Differential Equations ◽

Differential Equations ◽

Heat And Mass Transfer ◽

Fluidized Bed ◽

Solid Phase ◽

Variable Mass ◽

Partial Differential ◽

Large Particles ◽

Fluidized Bed Drying

A mathematical model for simulation of simultaneous unsteady heat and mass transfer in fluidized-bed drying of large particles is proposed. A set of coupled non-linear partial differential equations is employed to accurately model the process without using adjustable parameters. A three phase model representing a bubble (dilute) phase, interstitial gas phase and a solid phase is used to describe the thermal and hydrodynamic characteristics of the bed. The bubble and temperature distributions inside the solid phase is applied. The flow field is divided by an orthogonal grid to a finite number of control volumes to simulate the variation of the properties for the three phases in longitudinal direction. The Crank-Nicholson implicit numerical method is applied to solve the set of coupled nonlinear partial differential equations with variable mass and thermal diffusivity for a spherical-shape particle. A pilot-scaled fluidized bed dryer was built to test the results of proposed model with those obtained by experiments using wheat particles as a bed charge. A good agreement between the numerical and experimental results is observed.

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Resource-saving equipment for drying of dispersed materials in a fluidized bed

10.36652/0042-4633-2021-3-50-52 ◽

2021 ◽

pp. 50-52

Author(s):

Keyword(s):

Mass Transfer ◽

Heat And Mass Transfer ◽

Fluidized Bed ◽

Continuous Operation ◽

Resource Saving ◽

Fluidized Bed Drying

The design of dryers for bulk products with continuous operation is proposed. The regulation of the speed of the supplied air allows to increase the productivity and reliability of the equipment and to reduce its overall dimensions. Keywords: fluidized bed drying, heat and mass transfer, productivity, reliability. [email protected]

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Heat and mass transfer in batch fluidized-bed drying of porous particles

Chemical Engineering Science ◽

10.1016/s0009-2509(99)00446-7 ◽

2000 ◽

Vol 55 (10) ◽

pp. 1857-1869 ◽

Cited By ~ 53

Author(s):

Zhao Hui Wang ◽

Guohua Chen

Keyword(s):

Mass Transfer ◽

Heat And Mass Transfer ◽

Fluidized Bed ◽

Porous Particles ◽

Fluidized Bed Drying

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Hybrid Modeling of Modified Mathematical Model for Gas Phase Olefine in Fluidized Bed Catalyst Reactors Using Artificial Neural Networks

Chemical Product and Process Modeling ◽

10.2202/1934-2659.1431 ◽

2009 ◽

Vol 4 (1) ◽

Cited By ~ 1

Author(s):

Ahmmed Saadi Ibrehem

Keyword(s):

Heat Transfer ◽

Experimental Data ◽

Mass Transfer ◽

Heat And Mass Transfer ◽

Fluidized Bed ◽

Hybrid Model ◽

Operating Conditions ◽

Transfer Coefficients ◽

Mass And Heat Transfer ◽

Artificial Neural

The complex flow patterns induced in fluidized bed catalytic reactors and the competing parameters affecting the mass and heat transfer characteristics makes the design of such reactors a challenging task to accomplish. The models of such a process rely heavily on predictive empirical correlations for mass and heat transfer coefficients. Unfortunately, published empirical based correlations have the common shortcoming of low-prediction efficiency compared with experimental data. In this work, an artificial neural network approach is used to capture the reactor characteristics in terms of heat and mass transfer based on published experimental data. The developed ANN-based heat and mass transfer coefficients relations were used in a conventional FCR model and simulated under industrial operating conditions. The hybrid model predictions of the melt-flow index and the emulsion temperature were compared to industrial measurements as well as published models. The predictive quality of the hybrid model was superior to other models. This modeling approach can be used as an alternative to conventional modeling methods.

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