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Faustino Lopezrodriguez - One of the best experts on this subject based on the ideXlab platform.
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experimental modelling of infrared drying of industrial grape by products
Food and Bioproducts Processing, 2009Co-Authors: Ruiz A Celma, Faustino Lopezrodriguez, Cuadros F BlazquezAbstract:Abstract The thin-layer infrared drying behaviour of industrial grape by-products was experimentally investigated in the temperature range from 100 to 160 °C. The drying rate was found to increase with temperature, thus reducing the total drying time. In particular, as drying temperature was raised from 100 °C up to 160 °C, the time period needed to reduce the moisture content of the sample from 204.32% down to 38.89% by weight (dry basis) decreased from 60.5 to 21 min. Using a non-linear regression (Marquart's method) together with a multiple regression analysis, a mathematical model for the thin-layer infrared drying process of wet grape residues was proposed. The values for the Diffusivity Coefficients at each temperature were obtained using Fick's second law of diffusion. They varied from 11.013 × 10−9 to 26.050 × 10−9 m2/s along the temperature range. The temperature dependence of the effective Diffusivity Coefficient was expressed by an Arrhenius type relationship. Activation energy for the moisture diffusion was determined as 19.27 kJ/mol.
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characterisation of industrial tomato by products from infrared drying process
Food and Bioproducts Processing, 2009Co-Authors: Ruiz A Celma, Francisco Cuadros, Faustino LopezrodriguezAbstract:Abstract The thin-layer infrared drying behaviour of industrial tomato residues, peels and seeds, was experimentally investigated in the temperature range from 100 °C to 160 °C. The drying rate was found to increase with temperature, hence reducing the total drying time. In particular, as drying temperature was raised from 100 °C up to 160 °C, the time period needed to reduce the moisture content of the sample from 236.70 wt% down to 5.26 wt% (dry basis) was observed to decrease from 99.5 min to 35 min. Using a non-linear regression (Marquart's method) together with a multiple regression analysis, a mathematical model for the thin-layer infrared drying process of industrial tomato residues was proposed. The effective moisture Diffusivity is dependent on moisture content; the average values for the Diffusivity Coefficients at each temperature were obtained using Fick's second law of diffusion, and varied from 5.179 × 10−9 m2/s to 1.429 × 10−8 m2/s over the temperature range. The temperature dependence of the effective Diffusivity Coefficient was described following an Arrhenius-type relationship. Activation energy for the moisture diffusion was determined as 22.23 kJ/mol.
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mathematical modelling of thin layer infrared drying of wet olive husk
Chemical Engineering and Processing, 2008Co-Authors: Ruiz A Celma, S Rojas, Faustino LopezrodriguezAbstract:Abstract The thin-layer infrared drying behaviour of wet olive husk (WOH) was experimentally investigated at the temperature range from 80 °C to 140 °C. The drying rate was found to increase with temperature, hence reducing the total drying time. In particular, as drying temperature was raised from 80 °C up to 140 °C, the time necessary to reduce the moisture content of the sample from 91.97 wt% down to 8.69 wt% (dry basis) changed from 105 min to 35 min. Using a non-linear regression (Marquart's method) and multiple regression analysis, a mathematical model for the thin-layer infrared drying process of WOH was proposed. The values of the Diffusivity Coefficients at each temperature were obtained using Fick's second law of diffusion. They varied from 5.958 × 10 −9 m 2 /s to 1.589 × 10 −8 m 2 /s over the temperature range. The temperature dependence of the effective Diffusivity Coefficient was described following an Arrhenius-type relationship. Activation energy for the moisture diffusion was determined as 21.30 kJ/mol.
İbrahim Doymaz - One of the best experts on this subject based on the ideXlab platform.
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Determination of Sliced Pineapple Drying Characteristics in A Closed Loop Heat Pump Assisted Drying System
Diponegoro University, 2018Co-Authors: Cüneyt Tunçkal, İbrahim Doymaz, Salih Coşkun, Ernes ErgunAbstract:Pineapple (Ananascomosus) slices were dried with the aid of a heat pump assisted dryer (HPD). During this process, air velocity was kept constant at 1m/s, while air temperatures were changed as 37°C, 40°C and 43°C. The drying air was also circulated by using an axial fan in a closed cycle and fresh air was not allowed into the system. The drying rate and drying time were significantly influenced by drying temperature. It was observed that drying temperatures had significant effects on the drying rate and drying time. During the conduct of the study, pineapple slices were dried at 37, 40 and 43°C for 465, 360 and 290 min, respectively. The specific moisture extraction ratio (SMER) values were observed to change as drying temperatures were changed. The drying rate curves indicated that the whole drying process occurred in the falling rate period. Seven well-known thin-layer models (Lewis, Henderson &Pabis, Logarithmic, Page, Midilli & Kucuk, Weibull and Aghbashlo et al.) were employed to make a prediction about drying kinetics through nonlinear regression analysis. The Midilli & Kucuk and Aghbashlo et al. models were consistent with the experimental data. Fick’s second law of diffusion was used to determine the moisture Diffusivity Coefficient ranging from 3.78×10–9 to 6.57×10-9 m2/s the each of the above mentioned temperatures. The dependence of effective Diffusivity Coefficient on temperature was defined by means a fan Arrhenius type equation. The activation energy of moisture diffusion was found to be 75.24kJ/mol. Article History: Received: July 18th 2017; Received: October 27th 2017; Accepted: January 16th 2018; Available online How to Cite This Article: Tunçkal, C., Coşkun, S., Doymaz, I. and Ergun, E. (2018) Determination of Sliced Pineapple Drying Characteristics in A Closed Loop Heat Pump Assisted Drying System. International Journal of Renewable Energy Development, 7(1), 35-41. https://doi.org/10.14710/ijred.7.1.35-4
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modelling of olive cake thin layer drying process
Journal of Food Engineering, 2005Co-Authors: Nalan A Akgun, İbrahim DoymazAbstract:Abstract Olive cake is a sub-product of the mechanical olive oil extraction industry, which consists of pit and pulp of the olive fruit, olive oil and vegetable water. It has been using for direct combustion in bakeries and olive oil mills due to its energy content. However, the initial moisture content of olive cake is approximately 44.78% ± 0.5 (wet basis), and this has to be reduced to about 5% to recover its energy content. Therefore, the characterization of the thin layer drying kinetics was investigated at a wide range of drying temperatures (50–110 °C), a constant sample thickness and air velocity of 1.2 ± 0.03 m/s at a laboratory scale dryer. Various mathematical models simulated drying curves of olive cake. The logarithmic model was found to give better predictions than the others. In addition, the temperature dependence of the effective Diffusivity Coefficient was expressed by an Arrhenius type relationship. The effective Diffusivity varied between 0.3 and 1.1 × 10 −8 m 2 /s with an activation energy of 17.97 kJ/mol.
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drying characteristics of the solid by product of olive oil extraction
Biosystems Engineering, 2004Co-Authors: İbrahim Doymaz, O Gorel, Nalan A AkgunAbstract:Abstract Olive cake, the solid by-product of olive oil extraction, consists of pit and pulp of the olive fruit, and has significant oil content. Although the initial moisture content of olive cake is 44·78%±0·5 by weight (wet basis), the material has quite a high-energy content that enables it to be used for direct burning in bakeries and olive oil mills after sun drying in Turkey. When the latter manufacturing processes such as pomace oil production, bio-oil production by using thermal conversion processes were used, the effect of drying should be considered. Therefore, drying behaviour of olive cake in a cabinet type dryer was examined using heated ambient air at temperatures from 80 to 110°C and constant air velocity of 1·2 m s −1 in this study. In addition, the effects of sample thickness on the drying characteristics, drying time and energy quality of dried product were also determined. The experimental data was compared with values predicted by the Page model, and by the Henderson and Pabis model, good agreement being obtained with Page model. A diffusion model was used to describe the moisture transfer and the effective Diffusivity at each temperature was determined. The effective Diffusivity varied between 489·2 and 998·4 μm 2 s −1 . The temperature dependence of the Diffusivity Coefficient was also described by the Arrhenius type relationship. The activation energy was found to be 26·71 kJ mol −1 .
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effect of ethyl oleate on drying characteristics of mulberries
Nahrung-food, 2003Co-Authors: İbrahim Doymaz, Mehmet PalaAbstract:In this study, air-drying experiments in thin layers of mulberry grown in Istanbul, Turkey, were conducted. The effect of ethyl oleate solution on drying time of mulberry samples was investigated in a pilot air-dryer. When ethyl oleate was used as pretreatment solution, the drying time of samples was decreased. Drying curves were obtained using the Page model. The effective Diffusivity varied from 2.326 x 10(-10) to 1.809 x 10(-9) m2/s the temperature range. The temperature dependence of the Diffusivity Coefficient was described by the Arrhenius type relationship. The activation energy for moisture diffusion was found to be 50.87 kJ/mol for treated samples and 51.85 kJ/mol for untreated samples.
Ruiz A Celma - One of the best experts on this subject based on the ideXlab platform.
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experimental modelling of infrared drying of industrial grape by products
Food and Bioproducts Processing, 2009Co-Authors: Ruiz A Celma, Faustino Lopezrodriguez, Cuadros F BlazquezAbstract:Abstract The thin-layer infrared drying behaviour of industrial grape by-products was experimentally investigated in the temperature range from 100 to 160 °C. The drying rate was found to increase with temperature, thus reducing the total drying time. In particular, as drying temperature was raised from 100 °C up to 160 °C, the time period needed to reduce the moisture content of the sample from 204.32% down to 38.89% by weight (dry basis) decreased from 60.5 to 21 min. Using a non-linear regression (Marquart's method) together with a multiple regression analysis, a mathematical model for the thin-layer infrared drying process of wet grape residues was proposed. The values for the Diffusivity Coefficients at each temperature were obtained using Fick's second law of diffusion. They varied from 11.013 × 10−9 to 26.050 × 10−9 m2/s along the temperature range. The temperature dependence of the effective Diffusivity Coefficient was expressed by an Arrhenius type relationship. Activation energy for the moisture diffusion was determined as 19.27 kJ/mol.
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characterisation of industrial tomato by products from infrared drying process
Food and Bioproducts Processing, 2009Co-Authors: Ruiz A Celma, Francisco Cuadros, Faustino LopezrodriguezAbstract:Abstract The thin-layer infrared drying behaviour of industrial tomato residues, peels and seeds, was experimentally investigated in the temperature range from 100 °C to 160 °C. The drying rate was found to increase with temperature, hence reducing the total drying time. In particular, as drying temperature was raised from 100 °C up to 160 °C, the time period needed to reduce the moisture content of the sample from 236.70 wt% down to 5.26 wt% (dry basis) was observed to decrease from 99.5 min to 35 min. Using a non-linear regression (Marquart's method) together with a multiple regression analysis, a mathematical model for the thin-layer infrared drying process of industrial tomato residues was proposed. The effective moisture Diffusivity is dependent on moisture content; the average values for the Diffusivity Coefficients at each temperature were obtained using Fick's second law of diffusion, and varied from 5.179 × 10−9 m2/s to 1.429 × 10−8 m2/s over the temperature range. The temperature dependence of the effective Diffusivity Coefficient was described following an Arrhenius-type relationship. Activation energy for the moisture diffusion was determined as 22.23 kJ/mol.
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mathematical modelling of thin layer infrared drying of wet olive husk
Chemical Engineering and Processing, 2008Co-Authors: Ruiz A Celma, S Rojas, Faustino LopezrodriguezAbstract:Abstract The thin-layer infrared drying behaviour of wet olive husk (WOH) was experimentally investigated at the temperature range from 80 °C to 140 °C. The drying rate was found to increase with temperature, hence reducing the total drying time. In particular, as drying temperature was raised from 80 °C up to 140 °C, the time necessary to reduce the moisture content of the sample from 91.97 wt% down to 8.69 wt% (dry basis) changed from 105 min to 35 min. Using a non-linear regression (Marquart's method) and multiple regression analysis, a mathematical model for the thin-layer infrared drying process of WOH was proposed. The values of the Diffusivity Coefficients at each temperature were obtained using Fick's second law of diffusion. They varied from 5.958 × 10 −9 m 2 /s to 1.589 × 10 −8 m 2 /s over the temperature range. The temperature dependence of the effective Diffusivity Coefficient was described following an Arrhenius-type relationship. Activation energy for the moisture diffusion was determined as 21.30 kJ/mol.
L R Bedin - One of the best experts on this subject based on the ideXlab platform.
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cloud atlas unraveling the vertical cloud structure with the time series spectrophotometry of an unusually red brown dwarf
The Astrophysical Journal, 2020Co-Authors: Ben W P Lew, Daniel Apai, Mark S Marley, D Saumon, Glenn Schneider, Yifan Zhou, Nicolas B Cowan, Theodora Karalidi, Elena Manjavacas, L R BedinAbstract:Rotational modulations of emission spectra in brown dwarf and exoplanet atmospheres show that clouds are often distributed non-uniformly in these ultracool atmospheres. The spatial heterogeneity in cloud distribution demonstrates the impact of atmospheric dynamics on cloud formation and evolution. In this study, we update the Hubble Space Telescope (HST) time-series data analysis of the previously reported rotational modulations of WISEP J004701+680352 -- an unusually red late-L brown dwarf with a spectrum similar to that of the directly imaged planet HR8799e. We construct a self-consistent spatially heterogeneous cloud model to explain the Hubble Space Telescope and the Spitzer time-series observations, as well as the time-averaged spectra of WISE0047. In the heterogeneous cloud model, a cloud thickness variation of around one pressure scale height explains the wavelength dependence in the HST near-IR spectral variability. By including disequilibrium CO/$CH_4$ chemistry, our models also reproduce the redder $J-K_{\rm s}$ color of WISE0047 compared to that of field brown dwarfs. We discuss the impact of vertical cloud structure on atmospheric profile and estimate the minimum eddy Diffusivity Coefficient for other objects with redder colors. Our data analysis and forward modeling results demonstrate that time-series spectrophotometry with a broad wavelength coverage is a powerful tool for constraining heterogeneous atmospheric structure.
Onur Y Devres - One of the best experts on this subject based on the ideXlab platform.
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the thin layer drying characteristics of hazelnuts during roasting
Journal of Food Engineering, 1999Co-Authors: Onur Y DevresAbstract:Thin layer drying characteristics of hazelnuts during roasting were described for a temperature range of 100–160°C, using five semi-theoretical and two empirical thin layer models. The effective Diffusivity varied from 2.301×10−7 to 11.759×10−7 m2/s over the temperature range. Temperature dependence of the Diffusivity Coefficient was described by Arrhenius-type relationship. The activation energy for moisture diffusion was found to be 1891.6 kJ/kg. Thin layer drying characteristics of hazelnut roasting were satisfactorily described by an empirical Thompson model with the linear temperature dependence.