Experimental and mathematical study of the discontinuous drying kinetics of pears

Silva, Vítor; Figueiredo, A.R.; Costa, J.J.; Guiné, Raquel

doi:10.1016/j.jfoodeng.2014.02.022

Cited by 33 publications

(33 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Based on the results of Da Silva et al (2014) for continuous drying of whole bananas, three empirical equations (Table 2) were tested to fit the measured drying kinetics: M * (t) versus effective operation time. These empirical models will be fitted to the experimental datasets using LAB Fit Curve Fitting Software (www.labfit.net), which uses the Levenberg-Marquardt algorithm to determine the parameters of the equations.…”

Section: Empirical Modelsmentioning

confidence: 99%

“…The authors reported that there was good agreement between the simulated and experimental values, with standard error of less than 0.47%. An interesting study on intermittent drying was conducted by Silva et al (2014) using an analytical solution of the diffusion equation in spherical coordinates. In their solution, the initial moisture content distribution is not necessarily uniform and, this way, each tempering period was described providing the initial moisture content and establishing the convective mass transfer coefficient equal to zero.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Comparison between continuous and intermittent drying of whole bananas using empirical and diffusion models to describe the processes

Silva

Rodrígues

Silva

et al. 2015

Journal of Food Engineering

View full text Add to dashboard Cite

Section: Empirical Modelsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Comparison between continuous and intermittent drying of whole bananas using empirical and diffusion models to describe the processes

Silva

Rodrígues

Silva

et al. 2015

Journal of Food Engineering

View full text Add to dashboard Cite

“…Armut kurutma ve kuruma davranışlarının işlem özellikleri ile ilgili bazı çalışmalar yayınlanmıştır. Farklı armut türleri için [19], armut dilimleri için [20][21][22], osmotik-dehidrasyon ön işlemi uyguladıktan sonra [23,24], sitrik asit ile muamele ederek [21], kuruma sırasında meydana gelen büzülmeyi dikkate alarak [25,26] kurutma yapıldığı gibi, güneş enerjili kurutucularda kurutma [25], laboratuvar tipi konvekif kurutucularda kurutma [20,21] ve kesikli kurutma tekniği kullanılması [27] gibi farklı çalışmalar literatürde mevcuttur. Bu çalışmaların bazılarında kuruma sürecini açıklayan tek tabaka kuruma modelleri de tanımlanmışlardır [28].…”

Section: Gi̇ri̇ş (Introduction)unclassified

Farklı ön işlem uygulanan Ahlatın kuruma ve büzülme davranışının modellenmesi

Toğrul

Çelebi

Toğrul

2018

Gazi Üniversitesi Mühendislik-Mimarlık Fakültesi Dergisi

View full text Add to dashboard Cite

Highlights:Graphical/ Tabular Abstract  The effect of pretreatment and temperature on Ahlat drying  Modeling of drying and shrinkage behavior for non-researched Ahlat before  Calculation of the Diffusion Coefficient for the case where the diameter change is taken into account and not taken Model Adı Model Model Adı Model Newton MR=exp(-k.t) Rahman D/Do=1-a.(M-Mo) Page MR=exp(-k.tn) Ratti D/Do=a+b.(M/Mo) Henderson ve Pabis MR=a.exp(-k.t) Mayor ve Sereno D/Do= a.exp(b.M/Mo) Logaritmik MR=a.exp(-k.t)+c Correa ve ark. D/Do=1/(a+b.ln(M/Mo)) Midilli MR=a.exp(-k.t)n+c.t Hatamipour ve Mowla D/Do=a.ln(M)+b Kilpatrick, Lowe, and Van Ardsel D/Do=(M+a)/(Mo+a) Table A. Selected drying and shrinkage models Purpose: In this study, Ahlat (pyrus eleagrifolia) known as wild pear, was dried for four various drying temperatures (45-75 o C) in laboratory type dryer with and without pre-treatment. Theory and Methods: The pre-treatment solutions such as %65 maltose, sucrose, glucose, maltodekstrin, sorbitol and %55 sucrose-%10 salt %5 Na2SO5, %2 EO %5 Na2SO5, %5 K2SO5 and %2 EO %5K2SO5 was used in experiments. Dimensionless moisture content vs. drying time and drying rate vs. moisture content were investigated during drying Ahlat. Exchange of dimensionless moisture content vs time of ahlat was modelled by five model commonly used in literature. Shrinkage during drying Ahlat was investigated six models in literature. Models coefficients were tested in significance level p<0,05. The convenience between models and measured values was investigated by determination coefficient (R 2 ) and reduced chi square ( 2 ).Drying and shrinkage Models given in Table A were used for Ahlat drying. Results:Diffusion coefficients, characteristic transport coefficient for falling drying rate period, were determined with and without considering shrinkage for the whole drying temperatures and pre-treatments. There were obtained lower diffusion coefficients and lower activation energy by considering shrinkage. Conclusion:It was seen that the logarithmic model for non-pre-treatment, maltose, glucose, sucrose, sucrose-salt, %5 Na2S2O5, %2 EO %5 Na2S2O5 and %5 K2S2O5 pre-treatment and Newton model for sorbitol, maltodekstrin ve %2 EO %5K2S2O5 pre-treatment were convenient for drying Ahlat. It was seen that linear and exponential models were convenient the other models for explaining shrinkage.

show abstract

“…According to Chua et al (2003), intermittent drying is beneficial for drying systems controlled by diffusion effects inside the solid. It was observed that diffusion effects controlled the drying rates of a variety of agricultural products (AKPINAR et al, 2003;ARABHOSSEINI et al, 2009;BENALI, 2012;CHINENYE et al, 2010;CIL e TOPUZ, 2010;DEFENDI et al, 2015a;DEMIR et al, 2007;MEISAMI-ASL et al, 2010;OLIVEIRA e ROCHA, 2007;SILVA et al, 2014;VEGA-GÁLVEZ et al, 2012). For these products, there might be a waste of energy if the drying operation is continuously conducted at high temperature.…”

Section: Introductionmentioning

confidence: 99%

Assessment of Dryer Performance Under Intermittent Drying of Grains in Fixed Bed

Defendi

Paraíso²,

Jorge³

2017

Engevista

View full text Add to dashboard Cite

Resumo:A secagem intermitente é um tipo de operação que visa melhorar o desempenho do processo de secagem por meio de modulações das condições do ar como sua temperatura e velocidade na entrada do secador, contrariamente a operação convencional, na qual as condições do ar são mantidas em valores constantes. Este tipo alternativo de operação foca em determinar as melhores condições de modulação do ar a fim de minimizar o consumo energético, maximizar o desempenho do secador ou melhorar a qualidade do material. Neste contexto, este trabalho objetiva simular o processo de secagem de alguns grãos em leito fixo e avaliar se é possível aumentar com a operação intermitente o desempenho do secador em termos de taxa de secagem em comparação com resultados obtidos em operação convencional. Ambas as operações convencionais e intermitentes foram simuladas em condições de mesmo consumo energético relacionado à energia fornecida pelo ar na entrada do secador. Resultados apontaram que as taxas de secagem foram maiores em operação intermitente com modulação da temperatura do ar em comparação com os resultados obtidos em operação convencional com a temperatura do ar mantida em valores constantes. Além disso, observou-se em alguns casos que os valores de amplitude e período inerentes a estas modulações podem interferir nas taxas de secagem. Palavras-chave:Secagem intermitente, arroz, feijão, milho, soja.Abstract: Intermittent drying is an operation that aims to improve drying process performance with modulations of inlet air conditions such as its temperature and velocity, contrary to the conventional operation, in which air conditions are constant. This alternative operation aims to determine the best modulation pattern of air conditions to minimize energy consumption, maximize dryer performance or improve material quality. In this context, the objectives of this work are to simulate the drying process of some grains in fixed bed and assess if it is possible to enhance the dryer performance in terms of drying rates under intermittent operation in comparison with results obtained with conventional operation. Both intermittent and conventional operations were simulated with the same energy consumption related to the energy supplied by the air at the dryer entrance. Results revealed that the drying rates were higher under intermittence of inlet air temperature in comparison with results obtained under conventional operation with constant inlet air temperature. In addition, it was observed in some simulations that the amplitude and period values related to modulations can impact on drying rates.

show abstract

Experimental and mathematical study of the discontinuous drying kinetics of pears

Cited by 33 publications

References 25 publications

Comparison between continuous and intermittent drying of whole bananas using empirical and diffusion models to describe the processes

Comparison between continuous and intermittent drying of whole bananas using empirical and diffusion models to describe the processes

Farklı ön işlem uygulanan Ahlatın kuruma ve büzülme davranışının modellenmesi

Assessment of Dryer Performance Under Intermittent Drying of Grains in Fixed Bed

Contact Info

Product

Resources

About