scholarly journals Evaluation of energy efficiency and moisture diffusivity for convective drying of large cardamom

2021 ◽  
Vol 1020 ◽  
pp. 012016
Author(s):  
Soumya Dash ◽  
Kshirod Kumar Dash ◽  
Shibabrata Choudhury
Keyword(s):  
Energy Efficiency ◽  
Moisture Diffusivity ◽  
Convective Drying ◽  
Large Cardamom

Characteristics of sunflower seed drying and microwave energy consumption

2013 ◽  
Vol 27 (2) ◽  
pp. 127-132 ◽  
Author(s):  
H. Darvishi ◽  
M. Hadi Khoshtaghaza ◽  
G. Najafi ◽  
M. Zarein
Keyword(s):  
Energy Efficiency ◽  
Energy Consumption ◽  
Specific Energy ◽  
Microwave Power ◽  
Specific Energy Consumption ◽  
Moisture Diffusivity ◽  
Effective Moisture Diffusivity ◽  
Convective Drying ◽  
Drying Time ◽  
Effective Moisture

Abstract The effect of the microwave-convective drying technique on the moisture ratio, drying rate, drying time, effective moisture diffusivity, microwave specific energy consumption, and energy efficiency of sunflower seedswere investigated.Drying took place in the falling rate period. Increasing the microwave power caused a significant decrease in the drying time. The drying data were fitted to four thin-layer drying models. The performance of these models was compared using the coefficient of determination, reduced chi-square and root mean square error between the observed and predicted moisture ratios. The results showed that the Page model was found to satisfactorily describe themicrowave-convective drying curves of sunflower seeds. The effective moisture diffusivity values were estimated from Fick diffusion model and varied from 1.73 10-7 to 4.76 10-7m2s-1. Increasing the microwave power resulted in a considerable increase in drying efficiency and a significant decrease in microwave specific energy consumption. The highest energy efficiency and the lowestmicrowave specific energy consumption were obtained at the microwave power of 300 W.

scholarly journals Optimization and Prediction of the Drying and Quality of Turnip Slices by Convective-Infrared Dryer under Various Pretreatments by RSM and ANFIS Methods

Foods ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 284
Author(s):  
Ebrahim Taghinezhad ◽  
Mohammad Kaveh ◽  
Antoni Szumny
Keyword(s):  
Energy Efficiency ◽  
Color Difference ◽  
Moisture Diffusivity ◽  
Effective Moisture Diffusivity ◽  
Diffusivity Coefficient ◽  
Drying Process ◽  
Anfis Model ◽  
Drying Time ◽  
Effective Moisture ◽  
Response Variables

Drying can prolong the shelf life of a product by reducing microbial activities while facilitating its transportation and storage by decreasing the product weight and volume. The quality factors of the drying process are among the important issues in the drying of food and agricultural products. In this study, the effects of several independent variables such as the temperature of the drying air (50, 60, and 70 °C) and the thickness of the samples (2, 4, and 6 mm) were studied on the response variables including the quality indices (color difference and shrinkage) and drying factors (drying time, effective moisture diffusivity coefficient, specific energy consumption (SEC), energy efficiency and dryer efficiency) of the turnip slices dried by a hybrid convective-infrared (HCIR) dryer. Before drying, the samples were treated by three pretreatments: microwave (360 W for 2.5 min), ultrasonic (at 30 °C for 10 min) and blanching (at 90 °C for 2 min). The statistical analyses of the data and optimization of the drying process were achieved by the response surface method (RSM) and the response variables were predicted by the adaptive neuro-fuzzy inference system (ANFIS) model. The results indicated that an increase in the dryer temperature and a decline in the thickness of the sample can enhance the evaporation rate of the samples which will decrease the drying time (40–20 min), SEC (from 168.98 to 21.57 MJ/kg), color difference (from 50.59 to 15.38) and shrinkage (from 67.84% to 24.28%) while increasing the effective moisture diffusivity coefficient (from 1.007 × 10−9 to 8.11 × 10−9 m2/s), energy efficiency (from 0.89% to 15.23%) and dryer efficiency (from 2.11% to 21.2%). Compared to ultrasonic and blanching, microwave pretreatment increased the energy and drying efficiency; while the variations in the color and shrinkage were the lowest in the ultrasonic pretreatment. The optimal condition involved the temperature of 70 °C and sample thickness of 2 mm with the desirability above 0.89. The ANFIS model also managed to predict the response variables with R2 > 0.96.

A Numerical Approach to Determine Some Properties of Cylindrical Pieces of Bananas During Drying

2015 ◽  
Vol 11 (3) ◽  
pp. 335-347 ◽  
Author(s):  
Wilton Pereira da Silva ◽  
Cleide M. D. P. S. e Silva ◽  
Aluizio Freire da Silva Junior ◽  
Alexandre José de Melo Queiroz
Keyword(s):  
Numerical Solution ◽  
Numerical Approach ◽  
Moisture Diffusivity ◽  
Convective Drying ◽  
Chi Square ◽  
Experimental Conditions ◽  
Liquid Diffusion ◽  
Air Temperatures ◽  
C 50 ◽  
Volume Method

Abstract This article uses several liquid diffusion models to describe convective drying of bananas cut into cylindrical pieces. A two-dimensional numerical solution of the diffusion equation with boundary condition of the third kind, obtained through the finite volume method, was used to describe the process. The cylindrical pieces were cut into the following dimensions: length of about 21 mm and average radius of 15 mm. Drying air temperatures were 40°C, 50°C, 60°C and 70°C. In order to determine the process parameters, an optimizer was coupled with the numerical solution. A model that considers the shrinkage and variable effective moisture diffusivity well describes drying for all the experimental conditions, and enables to predict the moisture distributions at any given time. For this model, the determination coefficient has varied from 0.99937 (70°C) to 0.99995 (40°C), while the chi-square ranged from 3.41 × 10−4 (40°C) to 4.15 × 10−3 (70°C).

Inverse Approaches to Drying of Thin Bodies With Significant Shrinkage Effects

2006 ◽  
Vol 129 (3) ◽  
pp. 379-386 ◽  
Author(s):  
Gligor H. Kanevce ◽  
Ljubica P. Kanevce ◽  
Vangelce B. Mitrevski ◽  
George S. Dulikravich ◽  
Helcio R. B. Orlande
Keyword(s):  
Information Matrix ◽  
Optimization Method ◽  
Moisture Diffusivity ◽  
Temperature Fields ◽  
Convective Drying ◽  
Simultaneous Estimation ◽  
Transfer Coefficients ◽  
Unknown Parameters ◽  
Shrinkage Effect ◽  
Single Temperature

This paper deals with the application of inverse concepts to the drying of bodies that undergo changes in their dimensions. Simultaneous estimation is performed of moisture diffusivity, together with the thermal conductivity, heat capacity, density, and phase conversion factor of a drying body, as well as the heat and mass transfer coefficients and the relative humidity of drying air. This was accomplished by using only temperature measurements. A mathematical model of the drying process of shrinking bodies 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. The shrinkage effect was incorporated through the experimentally obtained changes of the specific volume of the drying body in an experimental convective dryer. The proposed method was applied to the process of drying potatoes. For the estimation of the unknown parameters, the transient readings of a single temperature sensor located in the midplane of the potato slice, 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. Analyses of the sensitivity coefficients and of the determinant of the information matrix are presented as well.

Modeling Some Drying Characteristics of Cantaloupe Slices

2012 ◽  
Vol 45 (2) ◽  
pp. 5-14 ◽  
Author(s):  
R. Chayjan ◽  
H. Agha-Alizade ◽  
H. Barikloo ◽  
B. Soleymani
Keyword(s):  
Air Temperature ◽  
Specific Energy ◽  
Specific Energy Consumption ◽  
Initial Moisture Content ◽  
Moisture Diffusivity ◽  
Convective Drying ◽  
Drying Characteristics ◽  
Thin Layer Drying ◽  
Temperature Levels ◽  
Drying Conditions

Modeling Some Drying Characteristics of Cantaloupe Slices This study investigated thin layer drying of cantaloupe slices under different drying conditions with initial moisture content about 18.53 (d.b.). Air temperature levels of 40, 50, 60 and 70°C were applied in drying of samples. Fick's second law in diffusion was applied to compute the effective moisture diffusivity (Deff) of cantaloupe slices. Minimum and maximum values of Deff were 4.05x10-10 and 1.61x10-9 m2/s, respectively. Deff values increased as the input air temperature was increased. Activation energy values of cantaloupe slices were found between 30.43 and 36.23 kJ/mol for 40°C to 70°C, respectively. The specific energy consumption for drying cantaloupe slices was calculated at the boundary of 1.01x105 and 9.55x105 kJ/kg. Increasing in drying air temperature in different air velocities led to increase in specific energy value. Results showed that applying the temperature of 70°C is more effective for convective drying of cantaloupe slices. The aforesaid drying parameters are important to select the best operational point of a dryer and to precise design of the system.

scholarly journals Determination of moisture diffusivity and activation energy in the convective drying of fish

2018 ◽  
Vol 36 (4) ◽  
pp. 1262-1267 ◽  
Author(s):  
Clement Adekunle Komolafe ◽  
Iyiola Olusola Oluwaleye ◽  
Akinfoye O. Daniel Adejumo ◽  
Mufutau Adekojo Waheed ◽  
Sidikat Ibiyemi Kuye
Keyword(s):  
Activation Energy ◽  
Moisture Diffusivity ◽  
Convective Drying

scholarly journals Drying characteristics and quality evaluation in convective drying of Cissus quadrangularis Linn.

2018 ◽  
Vol 192 ◽  
pp. 03041
Author(s):  
Setthawat Thanimkarn ◽  
Ekkapong Cheevitsopon ◽  
Jiraporn Sripinyowanich Jongyingcharoen
Keyword(s):  
Quality Evaluation ◽  
Moisture Diffusivity ◽  
Convective Drying ◽  
Total Phenolic ◽  
Drying Time ◽  
Drying Characteristics ◽  
Drying Temperature ◽  
Cissus Quadrangularis ◽  
Lower Bulk Density

This study aimed to investigate the effect of drying temperature (40, 60, 80, and 100°C) on drying characteristics of Cissus quadrangularis Linn. (CQ) undergoing convective drying. Physical properties and phytochemicals of the dried CQ were also evaluated. CQ with the thickness of 5 mm was dried from about 10 to 0.1 g water/g dry matter. The results showed that increasing drying temperature increased drying rate (DR) and effective moisture diffusivity (Deff) and consequently decreased drying time. The drying time, maximum DR, and Deff were in the ranges of 85-1920 min, 0.0059-0.0248 g water/g dry matter·min, and 0.7302-9.1281×10-9 m2/s, respectively. Lower drying temperature could preserve quality of the dried CQ. Decreasing drying temperature resulted in greener and lower bulk density and shrinkage. The greatest total phenolic content (TPC) and quercetin content were obtained by drying the CQ at 60°C.

scholarly journals Kinetics, energy efficiency and mathematical modeling of thin layer solar drying of figs (Ficus carica L.)

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Lahcen Hssaini ◽  
Rachida Ouaabou ◽  
Hafida Hanine ◽  
Rachid Razouk ◽  
Ali Idlimam
Keyword(s):  
Energy Efficiency ◽  
Thin Layer ◽  
Air Flow ◽  
Moisture Diffusivity ◽  
Energy Utilization ◽  
Ficus Carica ◽  
Effective Moisture Diffusivity ◽  
Drying Time ◽  
Effective Moisture ◽  
Thin Layer Drying

AbstractFirst convectional thin layer drying of two fig (Ficus carica L.) varieties growing in Moroccan, using partially indirect convective dryer, was performed. The experimental design combined three air temperatures levels (60, 70 and 80 °C) and two air-flow rates (150 and 300 m3/h). Fig drying curve was defined as a third-order polynomial equation linking the sample moisture content to the effective moisture diffusivity. The average activation energy was ranged between 4699.41 and 7502.37 kJ/kg. It raised proportionally with the air flow velocity, and the same pattern were observed for effective moisture diffusivity regarding drying time and velocity. High levels of temperature (80 °C) and velocity (300 m3/h) lead to shorten drying time (200 min) and improve the slices physical quality. Among the nine tested models, Modified Handerson and Pabis exhibited the highest correlation coefficient value with the lowest chi-square for both varieties, and then give the best prediction performance. Energetic investigation of the dryer prototype showed that the total use of energy alongside with the specific energy utilization (13.12 and 44.55 MWh/kg) were inversely proportional to the velocity and drying temperature. Likewise, the energy efficiency was greater (3.98%) higher in drying conditions.

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