Evaluation of a Moisture Diffusion Model for Analyzing the Convective Drying Kinetics of Lavandula x allardii Leaves

In the present case study, a moisture diffusion model is developed to simulate the drying kinetics of Lavandula x allardii leaves for non-stationary convective drying regimes. Increasing temperature profiles are applied over the drying duration and the influence of temperature advancing rates on the moisture removal and the drying rate is investigated. The model assumes a one-dimensional moisture transfer under transient conditions, which occurs from the leaf center to the surface by liquid diffusion due to the concentration gradient developed by the surface water evaporation caused by the difference of water vapor partial pressure between the drying medium and the leaf surface. A numerical solution of Fick’s 2nd law is obtained by an in-house code using the finite volume method, including shrinkage and a variable temperature-dependent effective moisture diffusion coefficient. The numerical results have been validated against experimental data for selected cases using statistical indices and the predicted dehydration curves presented a good agreement for the higher temperature advancing rates. The examined modeling approach was found stable and can output, in a computationally efficient way, the temporal changes of moisture and drying rate. Thus, the present model could be used for engineering applications involving the design, optimization and development of drying equipment and drying schedules for the examined type of non-stationary drying patterns.

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Study on drying kinetics of summer onion

Bangladesh Journal of Agricultural Research ◽

10.3329/bjar.v39i4.22545 ◽

2015 ◽

Vol 39 (4) ◽

pp. 661-673 ◽

Cited By ~ 1

Author(s):

Md Masud Alam ◽

Md Nurul Islam ◽

Md Nazrul Islam

Keyword(s):

Activation Energy ◽

Mass Transfer ◽

Rate Constant ◽

Variable Temperature ◽

Air Flow ◽

Drying Kinetics ◽

Effect Of Temperature ◽

Drying Rate ◽

External Resistance ◽

Kinetics Of

The present study was concerned with the kinetics of drying of summer onion. Drying was done in a mechanical dryer at constant air flow using blanched and unblanched onion with variable temperature (52, 60 and 680C) and thickness (3, 5 and 7 mm). Drying rate was increased with increase of temperature and decreased with the increase in thickness in blanched and unblanched onion. Blanched onion showed higher drying rate than unblanched onion. Drying rate constant and thickness can be expressed as power low equations. The value of index n were found to be 1.277 and 0.845 for onion indicating that the external resistance to mass transfer was highly significant. The effect of temperature on diffusion co-efficient follows an Arrhenius type relationship. The activation energy (Ea) for diffusion of water was found 5.781 Kcal/g-mole for unblanched and 2.46 Kcal/g-mole for blanched onion when onions were dried in mechanical dryer. DOI: http://dx.doi.org/10.3329/bjar.v39i4.22545 Bangladesh J. Agril. Res. 39(4): 661-673, December 2014

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Mathematical Modeling of Actinidia arguta (Kiwiberry) Drying Kinetics

Agricultural Engineering ◽

10.1515/agriceng-2017-0031 ◽

2017 ◽

Vol 21 (4) ◽

pp. 5-13 ◽

Cited By ~ 2

Author(s):

Michał Bialik ◽

Ewa Gondek ◽

Artur Wiktor ◽

Piotr Latocha ◽

Dorota Witrowa-Rajchert

Keyword(s):

Moisture Transfer ◽

Drying Kinetics ◽

Moisture Ratio ◽

Convective Drying ◽

Vacuum Drying ◽

Drying Methods ◽

Fruit Samples ◽

Bioactive Ingredients ◽

S Model ◽

Kinetics Of

AbstractConsumers and scientists exhibit a growing interest in bioactive ingredients of natural origin with strong pro-health effects. Such properties have been found in fruits of of Actinidia argute, commonly known as kiwiberry (mini kiwi or hardy kiwi). Appropriate methods and parameters of the drying process enable obtaining a product with preserved high pro-health properties. The obejctive of this paper was to study the influence of the selected drying methods on the drying kinetics of actinidia. Commonly known mathematical models were used to describe the process. The kinetics of convective, microwave-convective, infrared and vacuum drying was investigated. The process was performed until samples reached dimensionless moisture ratio (MR) of 0.02. The quickest method was vacuum drying reaching moisture ratio target after 286 min, and the slowest was convective drying characterized by 1352 min of drying. In general, Midilli et al.’s model was evaluated as the most adequate for description of the moisture transfer in the fruit samples.

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Modeling drying kinetics of Jacaranda mimosifolia seeds with variable effective diffusivity via diffusion model

Biosystems Engineering ◽

10.1016/j.biosystemseng.2021.03.008 ◽

2021 ◽

Vol 205 ◽

pp. 234-245

Author(s):

Marcos P. Felizardo ◽

Giovanni R.F. Merlo ◽

Gustavo D. Maia

Keyword(s):

Diffusion Model ◽

Effective Diffusivity ◽

Drying Kinetics ◽

Kinetics Of ◽

Jacaranda Mimosifolia

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Mathematical modeling of pequi pulp drying and effective diffusivity determination

Revista Brasileira de Engenharia Agrícola e Ambiental ◽

10.1590/1807-1929/agriambi.v21n7p493-498 ◽

2017 ◽

Vol 21 (7) ◽

pp. 493-498 ◽

Cited By ~ 3

Author(s):

Elisabete P. de Sousa ◽

Rossana M. F. de Figueirêdo ◽

Josivanda P. Gomes ◽

Alexandre J. de M. Queiroz ◽

Deise S. de Castro ◽

...

Keyword(s):

Experimental Data ◽

Effective Diffusivity ◽

Drying Kinetics ◽

Convective Drying ◽

Drying Time ◽

Air Speed ◽

Drying Curves ◽

Increasing Temperature ◽

Kinetics Of ◽

Best Fit

ABSTRACT The aim of this work was to study the drying kinetics of pequi pulp by convective drying at different conditions of temperature (50, 60, 70 and 80 °C) and thickness (0.5, 1.0 and 1.5 cm) at the air speed of 1.0 m s-1, with no addition of adjuvant. The experimental data of pequi pulp drying kinetics were used to plot drying curves and fitted to the models: Midilli, Page, Henderson & Pabis and Newton. Effective diffusivity was calculated using the Fick’s diffusion model for a flat plate. It was found that, with increasing thickness, the drying time increased and, with increasing temperature, the drying time was reduced. The Midilli model showed the best fit to the experimental data of pequi pulp drying at all temperatures and thicknesses, presenting higher coefficients of determination (R2), indicating that this model satisfactorily represents the pequi pulp drying phenomenon. There was a trend of increase in the effective diffusivity with the increase in pulp layer thickness and temperature.

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The Influence of Stainless Steel Mesh Porous Burner on Drying Kinetics of Nile Tilapia

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.805.116 ◽

2019 ◽

Vol 805 ◽

pp. 116-121

Author(s):

Pathiwat Waramit ◽

Apinunt Namkhat ◽

Umphisak Teeboonma

Keyword(s):

Stainless Steel ◽

Heat Source ◽

Nile Tilapia ◽

Drying Kinetics ◽

Drying Rate ◽

Air Velocity ◽

Stainless Steel Mesh ◽

Steel Mesh ◽

Porous Burner ◽

Kinetics Of

This paper studied the influence of porous burner effect on drying kinetics of Nile tilapia drying using stainless steel mesh porous burner as heat source. Drying kinetics was analyzed by determination of drying rate (DR), drying specific energy consumption (SEC) and dryer thermal efficiency (). In this study, the stainless steel mesh was used as porous media with porosity of 10, 20 and 50 pore per inch (PPI), drying air velocity of 0.5, 1.0 and 1.5 m/s, and drying temperature of 50, 60 and 70 °C, respectively. The results were found that the application of porous burner as heat source can improve the drying kinetics. It was found, at the porosity of 50 PPI, the drying temperature of 70 °C and the air velocity of 1.5 m/s, the moisture ratio of the drying was decreased rapidly, the highest drying rate was found to be 150 g (water evap.)/hr., the lowest drying energy consumption was found to be146.75 MJ/kg, and the thermal efficiency of the dryer was found to increase by 17.79% and the CO and NOx concentration in case of applying porous burner as heat source is lower than without porous burner.

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Convective Drying Kinetics of Polymer Strip Films Loaded with a BCS Class II Drug

AAPS PharmSciTech ◽

10.1208/s12249-018-1241-7 ◽

2019 ◽

Vol 20 (2) ◽

Cited By ~ 2

Author(s):

A. T. Naseri ◽

E. Cetindag ◽

J. Forte ◽

E. Bilgili ◽

Rajesh N. Davé

Keyword(s):

Class Ii ◽

Drying Kinetics ◽

Convective Drying ◽

Bcs Class Ii ◽

Kinetics Of

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Investigation of ultrasound-assisted convective drying process on quality characteristics and drying kinetics of zucchini slices

Heat and Mass Transfer ◽

10.1007/s00231-019-02573-6 ◽

2019 ◽

Vol 55 (8) ◽

pp. 2153-2163 ◽

Cited By ~ 3

Author(s):

Niloufar Bagheri ◽

Somayeh Taghian Dinani

Keyword(s):

Quality Characteristics ◽

Drying Kinetics ◽

Convective Drying ◽

Drying Process ◽

Ultrasound Assisted ◽

Kinetics Of

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Influence of Osmotic Pre-treatment on Convective Drying Kinetics of Figs

International Journal of Food Engineering ◽

10.1515/ijfe-2012-0020 ◽

2013 ◽

Vol 9 (2) ◽

pp. 187-196 ◽

Cited By ~ 8

Author(s):

Juliana M. Silva ◽

Muriel G. Cantu ◽

Vera Rodrigues ◽

Marcio A. Mazutti

Keyword(s):

Experimental Data ◽

Moisture Content ◽

Osmotic Dehydration ◽

Sucrose Concentration ◽

Drying Kinetics ◽

Soluble Solids ◽

Convective Drying ◽

Final Time ◽

Osmotic Treatment ◽

Kinetics Of

AbstractThis work evaluated the effects of osmotic dehydration on convective drying kinetics of figs. It used the experimental design methodology to evaluate the influence of sucrose concentration, temperature and time on the amount of total soluble solids (TSS) and moisture content of the figs. After the osmotic dehydration, it evaluated the convective drying kinetics at temperatures from 55 to 75°C. A mathematical model was employed to fit the experimental data. From the experimental data of the osmotic dehydration, it was seen that the moisture content of the figs after the treatment was closely related to the amount of TSS of the figs. Low moisture content and high TSS content were obtained for a narrow range of independent variables comprised between 55–60°C, 55–63 wt% and 260–280 min for temperature, sucrose concentration and exposure time, respectively. In the convective drying kinetics of the figs, there were no verified significant differences in the final time of drying of non-treated and osmotically dehydrated figs. However, the shrinkage was considerably reduced in the osmotically treated figs. The use of osmotic treatment enables the obtainment of figs softer than the simple use of convective drying without changing the final time of drying.

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