Journal articles: 'Convection drying'

1

Kumar, Mahesh, Pankaj Khatak, Ravinder Kumar Sahdev, and Om Prakash. "The effect of open sun and indoor forced convection on heat transfer coefficients for the drying of papad." Journal of Energy in Southern Africa 22, no. 2 (May 1, 2011): 40–46. http://dx.doi.org/10.17159/2413-3051/2011/v22i2a3214.

Full text

Abstract:

In this research paper, a simulation study has been carried out for the determination of convective heat transfer coefficients of papad under open sun drying and indoor forced convection drying modes. Experimental data obtained from open sun and indoor forced convection drying modes for papad were used to determine the values of the constants (C and n) in Nusselt number expression by using linear regression analysis, and consequently convective heat transfer coefficients were evaluated. The average values of convective heat transfer coefficients were found to be 3.54 and 1.56 W/m2 oC under open sun drying and indoor forced convection drying modes respectively. The experimental errors in terms of percent uncertainty were also evaluated.

APA, Harvard, Vancouver, ISO, and other styles

2

Moguel-Ordóñez, Yolanda B., Diana L. Cabrera-Amaro, Maira R. Segura-Campos, and Jorge C. Ruiz-Ruiz. "Studies on drying characteristic, nutritional composition, and antioxidant properties of Stevia rebaudiana (Bertoni) leaves." International Agrophysics 29, no. 3 (July 1, 2015): 323–31. http://dx.doi.org/10.1515/intag-2015-0039.

Full text

Abstract:

Abstract Drying characteristics of Stevia rebaudiana (Bertoni) leaves using radiation drying, convection drying, sun drying, and shade drying treatments were investigated in a convective type. Results for all treatments indicated that drying took place in the falling rate period. The chroma of the dried samples ranged between 29.66 and 23.85. Convection and shade drying samples were found better in colour and had the highest content of total pigments. The proximate and fibre composition were affected by the drying treatments. Extracts obtained from convection drying and shade drying leaves exhibited higher values of Trolox equivalent antioxidant capacities 416.89-423.64 mM mg−1 and ferric reducing power 85.19-87.97%. These extracts also showed ion chelating capacity 59.05-60.21% for Cu+2 and 55.05-59.11% for Fe+2. The results indicate that it is possible to select the drying treatment to obtain the best nutritional and biological properties. Convection drying and shade drying were the least aggressive treatments and leaf powders obtained by these drying methods could be used as sources of nutrients, fibre, and antioxidant compounds.

APA, Harvard, Vancouver, ISO, and other styles

3

EL-Mesery, Hany S., Abd El-Fatah Abomohra, Chan-Ung Kang, Ji-Kwang Cheon, Bikram Basak, and Byong-Hun Jeon. "Evaluation of Infrared Radiation Combined with Hot Air Convection for Energy-Efficient Drying of Biomass." Energies 12, no. 14 (July 22, 2019): 2818. http://dx.doi.org/10.3390/en12142818.

Full text

Abstract:

Cost-effective biomass drying is a key challenge for energy recovery from biomass by direct combustion, gasification, and pyrolysis. The aim of the present study was to optimize the process of biomass drying using hot air convection (HA), infrared (IR), and combined drying systems (IR-HA). The specific energy consumption (SEC) decreased significantly by increasing the drying temperature using convective drying, but higher air velocities increased the SEC. Similarly, increasing air velocity in the infrared dryer resulted in a significant increase in SEC. The lowest SEC was recorded at 7.8 MJ/kg at an air velocity of 0.5 m/s and an IR intensity of 0.30 W/cm2, while a maximum SEC (20.7 MJ/kg) was observed at 1.0 m/s and 0.15 W/cm2. However, a significant reduction in the SEC was noticed in the combined drying system. A minimum SEC of 3.8 MJ/kg was recorded using the combined infrared-hot air convection (IR-HA) drying system, which was 91.7% and 51.7% lower than convective and IR dryers, respectively. The present study suggested a combination of IR and hot air convection at 60 °C, 0.3 W/cm2 and 0.5 m/s as optimum conditions for efficient drying of biomass with a high water content.

APA, Harvard, Vancouver, ISO, and other styles

4

Mathuriya, Goldi. "Analysis Effects of Average Value of Convective and Evaporative Heat Transfer Coefficient on Solar Cabinet Dryer for Reduction of Mass of Papad." International Journal for Research in Applied Science and Engineering Technology 9, no. 12 (December 31, 2021): 1511–23. http://dx.doi.org/10.22214/ijraset.2021.39522.

Full text

Abstract:

Abstract: In this research paper, the behavior of heat and mass transfer phenomenon during greenhouse papad drying under forced convection mode has been investigated. Various experiments were performed during the month of April 2020 at SRCEM Banmore, morena (26o 34’13” N 78o 10’48” E). Experimental data obtained for forced convection greenhouse drying of papad were used to determine the constants in the Nusselt number expression by using the simple linear regression analysis and, consequently, the values of convective and evaporative heat transfer coefficients were evaluated. The average values of experimental constants C and n were determined as 0.9714 and 0.0129 respectively. The average values of convective and evaporative heat transfer coefficients were determined as 0.0886 W/m2 oC and 6.7583 W/m2 oC respectively. The experimental error in terms of percentage uncertainty was also evaluated. Keywords: Papad, Papad drying, Heat transfer coefficient, Convective, Evaporative, Forced convection greenhouse

APA, Harvard, Vancouver, ISO, and other styles

5

Kumar, Mahesh. "Experimental study on natural convection greenhouse drying of papad." Journal of Energy in Southern Africa 24, no. 4 (November 1, 2013): 37–43. http://dx.doi.org/10.17159/2413-3051/2013/v24i4a3144.

Full text

Abstract:

In this paper, the convective heat transfer coefficients of papad for greenhouse drying under a natural convection mode are reported. Various experiments were conducted during the month of April 2010 at Guru Jambheshwar University of Science and Technology Hisar, India (29o5’5” N 75o45’55” E). Experimental data obtained for the natural convection greenhouse drying of papad was used to evaluate the constants in the Nusselt number expression by using simple linear regression analysis. These values of the constant were used further to determine the values of the convective heat transfer coefficient. The average value of a convective heat transfer coefficient was determined as 1.23 W/m2 oC. The experimental error in terms of percent uncertainty was also evaluated.

APA, Harvard, Vancouver, ISO, and other styles

6

Barreto, Alberto A., Mauri Fortes, Wanyr R. Ferreira, and Luiz C. A. Crespo. "Transport coefficients for low and high-rate mass transfer along a biological horizontal cylinder." Revista Brasileira de Engenharia Agrícola e Ambiental 10, no. 2 (June 2006): 441–47. http://dx.doi.org/10.1590/s1415-43662006000200027.

Full text

Abstract:

Knowledge of heat and mass transfer coefficients is essential for drying simulation studies or design of food and grain thermal processes, including drying. This work presents the full development of a segregated finite element method to solve convection-diffusion problems. The developed scheme allows solving the incompressible, steady-state Navier-Stokes equations and convective-diffusive problems with temperature and moisture dependent properties. The problem of simultaneous energy, momentum and species transfer along an infinite, horizontal cylinder under drying conditions in forced convection is presented, considering conditions normally found in biological material thermal treatment or drying. Numerical results for Nusselt and Sherwood numbers were compared against available empirical expressions; the results agreed within the associated experimental errors. For high rate mass transport processes, the proposed methodology allows to simulate drying conditions involving wall convective mass flux by a simple inclusion of the appropriated boundary conditions.

APA, Harvard, Vancouver, ISO, and other styles

7

Martínez-Castaño, Marcela, Diana Paola Mejía Díaz, José Contreras-Calderón, and Cecilia Gallardo Cabrera. "Physicochemical properties of bean pod (Phaseolus vulgaris) flour and its potential as a raw material for the food industry." Revista Facultad Nacional de Agronomía Medellín 73, no. 2 (May 1, 2020): 9179–87. http://dx.doi.org/10.15446/rfnam.v73n2.81564.

Full text

Abstract:

The sustainable development of agro-industry requires the efficient use of all raw matters, which implies physicochemical and functional studies of by-products for finding their potential usage in industrial processes. The objective of the present study was to assess some physicochemical and functional properties of fIour obtained from the bean pod. Two types of drying methods were tested: convection and vacuum. The fIours tended to yellow color according to b* parameter values (convection drying: 17.54; vacuum drying: 18.35), with a slight red hue. They also showed high water-holding (convection drying: 8.30 g g-1; vacuum drying: 7.56 g g-1) and oil holding capacity (convection drying: 2.53 g g-1; vacuum drying: 2.56 g g-1), polyphenols content (convection drying: 26.62 mg GAE g-1 DW; vacuum drying: 3.77 mg GAE g-1 DW) and antioxidant capacity (convection drying: 33.42 µmol Trolox g-1; vacuum drying: 5.27 µmol Trolox g-1). The results were similar for the two types of drying methods, except for the antioxidant capacity. Since convection drying is more economical and available than vacuum drying, only the fIour obtained by convection method was analyzed on compositional and structural characteristics. This fIour showed to be a good source of dietary fiber (66.93%), being the insoluble fiber the predominant fraction (59.97%). Moreover, a high content of ash (6.65%) and low lipid content (0.58%) were also found. The IR spectrum showed signs corroborating the presence of dietary fiber, which also was evidenced morphologically. Overall, the results obtained indicated that the bean pod fIour obtained by convection drying has potential use as a raw material for the food industry.

APA, Harvard, Vancouver, ISO, and other styles

8

Adabi, Esmaeili, Ali Motevali, Ali Nikbakht, and Hadi Khoshtaghaza. "Investigation of some pretreatments on energy and specific energy consumption drying of black mulberry." Chemical Industry and Chemical Engineering Quarterly 19, no. 1 (2013): 89–105. http://dx.doi.org/10.2298/ciceq111120045a.

Full text

Abstract:

Massive consumption of energy in drying industry makes it a matter of challenge regarding economical aspects and limited recourses. Several methods for drying including hot air convection, vacuum, infrared and hot air convection-infrared technologies were applied in order to estimate the consumed energy during the drying of mulberry fruit. Moreover, microwave heating, chemical (ethyl oleate and potassium), mechanical (ultrasonic) and blanching (hot water) pretreatments were compared. According to the Results, maximum energy consumption was recorded when no pretreatment was performed. Microwave heating in the hot air convection-infrared dryer resulted in the lowest consumption of energy. Total energy requirement decreased with the temperature in the convection dryer res. Conversely, energy increased with air velocity. The vacuum dryer consumed the highest amount of energy which was measured to be 46.95 kWh while the lowest energy was recorded with using infrared-convective dryers. Also Experimental results showed that minimum and maximum specific energy consumption in the drying of black mulberry were associated with microwave pretreatment in IR-hot air dryer and control treatment in vacuum dryer, respectively. The minimum color change (?E) for drying of black mulberry was found in microwave pretreated samples dried with the vacuum dryer, yet maximum ?E was observed in hot air dryer when no pretreatment was applied.

APA, Harvard, Vancouver, ISO, and other styles

9

Inoue, Kuniaki, and Larissa E. Back. "Gross Moist Stability Assessment during TOGA COARE: Various Interpretations of Gross Moist Stability." Journal of the Atmospheric Sciences 72, no. 11 (November 1, 2015): 4148–66. http://dx.doi.org/10.1175/jas-d-15-0092.1.

Full text

Abstract:

Abstract Daily averaged TOGA COARE data are analyzed to investigate the convective amplification/decay mechanisms. The gross moist stability (GMS), which represents moist static energy (MSE) export efficiency by large-scale circulations associated with the convection, is studied together with two quantities, called the critical GMS (a ratio of diabatic forcing to the convective intensity) and the drying efficiency [a version of the effective GMS (GMS minus critical GMS)]. The analyses reveal that convection intensifies (decays) via negative (positive) drying efficiency. The authors illustrate that variability of the drying efficiency during the convective amplifying phase is predominantly explained by the vertical MSE advection (or vertical GMS), which imports MSE via bottom-heavy vertical velocity profiles (associated with negative vertical GMS) and eventually starts exporting MSE via top-heavy profiles (associated with positive vertical GMS). The variability of the drying efficiency during the decaying phase is, in contrast, explained by the horizontal MSE advection. The critical GMS, which is moistening efficiency due to the diabatic forcing, is broadly constant throughout the convective life cycle, indicating that the diabatic forcing always tends to destabilize the convective system in a constant manner. The authors propose various ways of computing quasi-time-independent “characteristic GMS” and demonstrate that all of them are equivalent and can be interpreted as (i) the critical GMS, (ii) the GMS at the maximum precipitation, and (iii) a combination of feedback constants between the radiation, evaporation, and convection. Those interpretations indicate that each convective life cycle is a fluctuation of rapidly changing GMS around slowly changing characteristic GMS.

APA, Harvard, Vancouver, ISO, and other styles

10

Grandpeix, Jean-Yves, and Jean-Philippe Lafore. "A Density Current Parameterization Coupled with Emanuel’s Convection Scheme. Part I: The Models." Journal of the Atmospheric Sciences 67, no. 4 (April 1, 2010): 881–97. http://dx.doi.org/10.1175/2009jas3044.1.

Full text

Abstract:

Abstract The aim of the present series of papers is to develop a density current parameterization for global circulation models. This first paper is devoted to the presentation of this new wake parameterization coupled with Emanuel’s convective scheme. The model represents a population of identical circular cold pools (the wakes) with vertical frontiers. The wakes are cooled by the precipitating downdrafts while the outside area is warmed by the subsidence induced by the saturated drafts. The budget equations for mass, energy, and water yield evolution equations for the prognostic variables (the vertical profiles of the temperature and humidity differences between the wakes and their exterior). They also provide additional terms for the equations of the mean variables. The driving terms of the wake equations are the differential heating and drying due to convective drafts. The action of the convection on the wakes is implemented by splitting the convective tendency and attributing the effect of the precipitating downdrafts to the wake region and the effect of the saturated drafts to their exterior. Conversely, the action of the wakes on convection is implemented by introducing two new variables representing the convergence at the leading edge of the wakes. The available lifting energy (ALE) determines the triggers of deep convection: convection occurs when ALE exceeds the convective inhibition. The available lifting power (ALP) determines the intensity of convection; it is equal to the power input into the system by the collapse of the wakes. The ALE/ALP closure, together with the splitting of the convective heating and drying, implements the full coupling between wake and convection. The coupled wake–convection scheme thus created makes it possible to represent the moist convective processes more realistically, to prepare the coupling of convection with boundary layer and orographic processes, and to consider simulating the propagation of convective systems.

APA, Harvard, Vancouver, ISO, and other styles

11

Lobachevsky, Ya P., and S. A. Pavlov. "Infrared Drying of Seeds in a Fluidized Bed." Agricultural Machinery and Technologies 12, no. 5 (November 8, 2018): 39–43. http://dx.doi.org/10.22314/2618-6748-2018-12-5-39-43.

Full text

Abstract:

Infrared drying (IR) has found wide application mainly in the food industry. Seeds of cereal crops are dried mainly by a convection method using shaft, column and bunker dryers. Such drying methods are ineffective, they are characterized by low productivity and high specific heat costs. The author has studied some methods of drying ensuring high intensity of the process with the maximum preservation of the quality of seeds. One of them is combined infrared drying. Combined modes of IR drying have a number of advantages over convection drying - quick heating of the particles ensures shortened process time, and the combination of diffusion and thermal diffusion processes facilitates the transfer of moisture from the grain mass center to the periphery, which reduces the specific heat consumption of a drying process. The author has considered a combined method with the use of a fluidized bed with a low intensity of the IR flow, with an additional supply of heat by the heated external air.(Research purpose)To develop a mathematical model of convective radiation IR drying of seeds, to calculate the surface temperature, the power of an IR-emitter, and the parameters of air heating.(Materials and methods)The parameters of combined IR drying have been determined using the regularities characteristic for convective drying, but with an equivalent heat transfer coefficient. The temperature and power of the IR energy source have been determined on the basis of permissible heat supply. The author has experimentally evaluated the efficiency of IR drying with blowing by external and heated air with convection drying.(Results and discussion)The surface temperature and the power of an IR emitter depend on the thickness of the layer, physical- and mechanical and radiological properties of seeds, permissible heat content and heat spent on the evaporation of moisture. It has been established that the exposure of combined drying is 12 percent lower than that of convective drying due to the process intensification with full preservation of the quality parameters of seeds.(Conclusions)The surface temperature and power of an IR emitter have been calculated as a function of the layer height, physical-and-mechanical and radiological properties of seeds, permissible heat content and heat spent on the evaporation of moisture. The degree of air heating with combined IR drying is proportional to the power deficit of an IR emitter and is inversely proportional to the equivalent heat transfer coefficient.

APA, Harvard, Vancouver, ISO, and other styles

12

Tomas, S., D. Skansi, and M. Sokele. "Convection drying of porous material." Ceramics International 20, no. 1 (January 1994): 9–16. http://dx.doi.org/10.1016/0272-8842(94)90003-5.

Full text

APA, Harvard, Vancouver, ISO, and other styles

13

Krzykowski, Andrzej, Dariusz Dziki, Stanisław Rudy, Urszula Gawlik-Dziki, Emilia Janiszewska-Turak, and Beata Biernacka. "Wild Strawberry Fragaria vesca L.: Kinetics of Fruit Drying and Quality Characteristics of the Dried Fruits." Processes 8, no. 10 (October 8, 2020): 1265. http://dx.doi.org/10.3390/pr8101265.

Full text

Abstract:

The aim of this study was to determine the effect of the temperature of convection and freeze–drying of wild strawberry Fragaria vesca L. fruits on the drying kinetics and on selected quality features of the dried fruits. The process of convection drying was carried out at the temperatures of 25 °C, 40 °C, and 60 °C, whereas freeze–drying was carried out at the temperatures of 20 °C, 40 °C, and 60 °C of the heating shelves and at the pressure of 63 Pa in the lyophilizer chamber. The drying kinetics were best described by the Midilli model for both drying methods. An increase of the drying temperature to 60 °C, for both convection drying and freeze–drying, resulted in a decrease of the total content of phenolic compounds and of the antioxidant activity of the dried fruits. An increase in the temperature of convection drying reduced the lightness of the dried fruits. However, during freeze–drying, these features changed little despite the increase in the drying temperature. The dried fruits with the highest brightness were obtained at a freeze–drying temperature of 60 °C. The method of freeze–drying is proposed as the best because of the resulting color, L-ascorbic acid retention, and antioxidant properties of the dried fruits.

APA, Harvard, Vancouver, ISO, and other styles

14

Chen, Diwu, Andrew Duff, and John Willcocks. "The application of dynamic modelling technique on the pipeline drying operation during pre-commissioning." APPEA Journal 60, no. 2 (2020): 606. http://dx.doi.org/10.1071/aj19144.

Full text

Abstract:

The objective of pipeline drying during pre-commissioning is to remove residual water left in the pipeline after dewatering and desalination operations. Removing the residual water mitigates corrosion and hydrate formation and aids quicker delivery of product to required dryness. The common pipeline drying methods are vacuum drying and convection drying. The convection drying method blows dry air through the pipeline to remove the residual water. Its disadvantages are an inability to adequately dry complex-shaped pipeline networks, significant equipment footprint and expelling air noise during the convection drying operation. The vacuum drying method can achieve low dewpoints particularly for complex-shaped pipeline networks and the equipment footprint can also be smaller than for the convection drying method. Therefore, it is advantageous when facing space restrictions for equipment. This paper introduces a dynamic integrated model to simulate the pipeline drying operation. This model considers vacuum pump performance and gas saturation condition in the pipeline during the drying operation. The modelling results can be used to determine the vacuum drying suitability, predict the drying operation duration and identify opportunities to improve the pipeline drying efficiency, such as vacuum pump performance, dry gas injection and convection dry air flow rate. It also demonstrates where vacuum drying is unlikely to be feasible, i.e. low ambient temperature conditions, and methods for identifying such. An optimisation case study is also presented. The drying duration can be reduced significantly by integrating vacuum drying with dry gas injection. This combined methodology can thus significantly improve the pipeline vacuum drying efficiency, which reduces the project cost and improves and de-risks scheduled and simultaneous operations.

APA, Harvard, Vancouver, ISO, and other styles

15

Afanas’ev, Anatoly M., Arina V. Nikishova, and Boris N. Siplivy. "TRANSIENTS PROCESSES UNDER DRYING WITH CONVECTION AND INFRARED RADIATION." IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENIY KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 60, no. 10 (November 16, 2017): 94. http://dx.doi.org/10.6060/tcct.20176010.5568.

Full text

Abstract:

Based on the theory of the A.V. Lykov for heat and mass transfer the mathematical model of propagation of heat and moisture in a flat sample, which is blown by the air flow and is exposed to infrared radiation. The model is based on the following views: the density of heat loss is determined by the heat transfer by convection and heat exchange by radiation, and the intensity of the mass exchange surface with the environment depends on the difference in partial pressure of water vapor through the thickness of the boundary layer (the boundary condition of mass transfer in the form of Dalton); temperature field inside the material is determined by the heat transfer due to the phenomenon of thermal conductivity, and the presence of internal heat sources caused by the absorption of penetrating electromagnetic radiation and the processes of evaporation (condensation); the transfer of moisture inside the material is partly liquid and partly in vapor form, and is caused by moisture content gradients (diffusion) and temperature (thermal diffusion). The results of analytical calculation of steady-state fields of temperature and moisture content for cases of convective drying and infrared drying, and the results of numerical calculation of the same field in transient conditions are presented. Numerical experiment allows us to estimate the duration of the transition process, as well as the behavior of the differential moisture content between the borders of the plate, with the increase which increases the probability of failure of the sample from mechanical deformation. It is shown that for convective drying of such a danger occurs in the transitional regime, and for infrared drying – mode steady-state. To reduce internal mechanical stresses when drying by convection, avoid sudden temperature changes of the air flow; the time during which there is an increase in air temperature, should be around the time of the transition process. When drying with infrared rays, if the differences of moisture content in the steady state are invalid for their reduction can be used or drying in the oscillating radiation, or drying under the combined effect of the sample electromagnetic waves with large and small penetration depth. The distinction in the nature of transients, infrared drying and drying with hot air can be explained using the formula of Dalton, which is part of the used mathematical model and determining the intensity of the problem through the boundary layer. Due to the great inertia of thermal processes, even in the case where the intensity of the infrared radiation changes rapidly in time (for example at the initial time gap of the first kind), the surface temperature of the material, and with it the intensity of drying, continue to be continuous functions; on the contrary, an abrupt change in air temperature in convective drier automatically leads to a gap function of the flux density of moisture on the surface.Forcitation:Afanas'ev A.M., Nikishova A.V., Siplivy B.N. Transients processes under drying with convection and infrared radiation. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2017. V. 60. N 10. P. 94-101

APA, Harvard, Vancouver, ISO, and other styles

16

Isinkaye, J. T., J. S. Oghenekaro, and O. D. Isinkaye. "Development of a forced convection electric fish drying machine." Environmental Technology and Science Journal 12, no. 2 (April 22, 2022): 82–90. http://dx.doi.org/10.4314/etsj.v12i2.8.

Full text

Abstract:

A forced convection electric fish dryer was developed in this study to provide an efficient means of drying fish in urban and rural areas and serve as a substitute for the largely inefficient local means of drying fish. The machine was designed to accommodate 126 kg of fish distributed accordingly within the drying chamber. Six flat electric coils of 3 kW capacity each and a fan blower were provided to induce a saturating forced convective current within the drying chamber. The machine was evaluated at a drying temperature of 60oC with a total of 126 kg catfish, 21 kg on each tray. The result showed that percentage moisture contents of 81.8%, 72.7%, 62.7%, 54.1%, 47.7%, and 40.9 % were evaporated from the fish on the sixth to the first tray respectively in one hour. The mean percentage of moisture evaporated from all the trays was 60 %.

APA, Harvard, Vancouver, ISO, and other styles

17

Isinkaye, J. T., J. S. Oghenekaro, and O. D. Isinkaye. "Development of a forced convection electric fish drying machine." Environmental Technology and Science Journal 12, no. 2 (April 22, 2022): 82–90. http://dx.doi.org/10.4314/etsj.v12i2.8.

Full text

Abstract:

A forced convection electric fish dryer was developed in this study to provide an efficient means of drying fish in urban and rural areas and serve as a substitute for the largely inefficient local means of drying fish. The machine was designed to accommodate 126 kg of fish distributed accordingly within the drying chamber. Six flat electric coils of 3 kW capacity each and a fan blower were provided to induce a saturating forced convective current within the drying chamber. The machine was evaluated at a drying temperature of 60oC with a total of 126 kg catfish, 21 kg on each tray. The result showed that percentage moisture contents of 81.8%, 72.7%, 62.7%, 54.1%, 47.7%, and 40.9 % were evaporated from the fish on the sixth to the first tray respectively in one hour. The mean percentage of moisture evaporated from all the trays was 60 %.

APA, Harvard, Vancouver, ISO, and other styles

18

Isinkaye, J. T., J. S. Oghenekaro, and O. D. Isinkaye. "Development of a forced convection electric fish drying machine." Environmental Technology and Science Journal 12, no. 2 (April 22, 2022): 82–90. http://dx.doi.org/10.4314/etsj.v12i2.8.

Full text

Abstract:

A forced convection electric fish dryer was developed in this study to provide an efficient means of drying fish in urban and rural areas and serve as a substitute for the largely inefficient local means of drying fish. The machine was designed to accommodate 126 kg of fish distributed accordingly within the drying chamber. Six flat electric coils of 3 kW capacity each and a fan blower were provided to induce a saturating forced convective current within the drying chamber. The machine was evaluated at a drying temperature of 60oC with a total of 126 kg catfish, 21 kg on each tray. The result showed that percentage moisture contents of 81.8%, 72.7%, 62.7%, 54.1%, 47.7%, and 40.9 % were evaporated from the fish on the sixth to the first tray respectively in one hour. The mean percentage of moisture evaporated from all the trays was 60 %.

APA, Harvard, Vancouver, ISO, and other styles

19

Bouhdjar, Amor, Hakim Semai, Amal Boukadoum, Sofiane Elmokretar, Azzedine Mazari, Mohamed Semiani, and Aissa Amari. "Improved Procedure for Natural Convection Garlic Drying." Acta Technologica Agriculturae 23, no. 2 (June 1, 2020): 92–98. http://dx.doi.org/10.2478/ata-2020-0015.

Full text

Abstract:

AbstractVegetable drying is an energy consuming procedure despite the fact that it is the most efficient way to preserve agricultural products. This study investigates a new way to dry good quality garlic at lower cost. Thin garlic layer was submitted to free convection airflow at air drying temperature of 40 °C, 50 °C, and 60 °C. Using the slope method, effective diffusivity coefficient was determined at each drying temperature during the first and second falling drying rate periods. Considering the former, it increased with increasing temperature. In relation to latter, it decreased with the temperature increase. However, at low drying temperatures, process keeps on going to very low moisture content; and it develops to an asymptotic value at high temperatures, indicating that shrinking at high temperature prevents evaporation of some residual moisture. Considered separately, these temperatures do not reflect the conditions met in solar drying, since in solar systems, air temperature increases during the day with increasing solar radiation. Therefore, characterization of garlic drying by means of step temperature varying – the first hour of drying at 40 °C; the second hour of drying at 50 °C, and the remaining time of drying at 60 °C – might better correspond with conditions under solar drying and result in better understanding of the process.

APA, Harvard, Vancouver, ISO, and other styles

20

Sahdev, Ravinder Kumar, Mahesh Kumar, and Ashwani Kumar Dhingra. "FORCED CONVECTION DRYING OF INDIAN GROUNDNUT: AN EXPERIMENTAL STUDY." Facta Universitatis, Series: Mechanical Engineering 15, no. 3 (December 9, 2017): 467. http://dx.doi.org/10.22190/fume160812011s.

Full text

Abstract:

In this paper, convective and evaporative heat transfer coefficients of the Indian groundnut were computed under indoor forced convection drying (IFCD) mode. The groundnuts were dried as a single thin layer with the help of a laboratory dryer till the optimum safe moisture storage level of 8 – 10%. The experimental data were used to determine the values of experimental constants C and n in the Nusselt number expression by a simple linear regression analysis and consequently, the convective heat transfer coefficient (CHTC) was determined. The values of CHTC were used to calculate the evaporative heat transfer coefficient (EHTC). The average values of CHTC and EHTC were found to be 2.48 W/m2 oC and 35.08 W/m2 oC, respectively. The experimental error in terms of percent uncertainty was also estimated. The experimental error in terms of percent uncertainty was found to be 42.55%. The error bars for convective and evaporative heat transfer coefficients are also shown for the groundnut drying under IFCD condition.

APA, Harvard, Vancouver, ISO, and other styles

21

Owusu-Kwarteng, James, Francis K. K. Kori, and Fortune Akabanda. "Effects of Blanching and Natural Convection Solar Drying on Quality Characteristics of Red Pepper (Capsicum annuum L.)." International Journal of Food Science 2017 (2017): 1–6. http://dx.doi.org/10.1155/2017/4656814.

Full text

Abstract:

The objective of this work was to determine the effects of blanching and two drying methods, open-sun drying and natural convection solar drying, on the quality characteristics of red pepper. A 2 × 3 factorial design with experimental factors as 2 drying methods (open-sun drying and use of solar dryer) and 3 levels of pepper blanching (unblanched, blanched in plain water, and blanched in 2% NaCl) was conducted. Dried pepper samples were analysed for chemical composition, microbial load, and consumer sensory acceptability. Blanching of pepper in 2% NaCl solution followed by drying in a natural convection solar dryer reduced drying time by 15 hours. Similarly, a combination of blanching and drying in the solar dryer improved microbial quality of dried pepper. However, blanching and drying processes resulted in reduction in nutrients such as vitamin C and minerals content of pepper. Blanching followed by drying in natural convection solar dryer had the highest consumer acceptability scores for colour and overall acceptability, while texture and aroma were not significantly (p>0.05) affected by the different treatments. Therefore, natural convection solar dryer can be used to dry pepper with acceptable microbial and sensory qualities, as an alternative to open-sun drying.

APA, Harvard, Vancouver, ISO, and other styles

22

Szentgyörgyi, S., L. Tömösy, and O. Molnár. "CONVECTION HEAT TRANSEER COEFFICIENTS AT CONVECTIVE DRYING OF POROUS MATERIALS∗." Drying Technology 18, no. 6 (July 2000): 1287–304. http://dx.doi.org/10.1080/07373930008917777.

Full text

APA, Harvard, Vancouver, ISO, and other styles

23

Feng, Tao, Jia-Yuh Yu, Xiu-Qun Yang, and Ronghui Huang. "Convective Coupling in Tropical-Depression-Type Waves. Part II: Moisture and Moist Static Energy Budgets." Journal of the Atmospheric Sciences 77, no. 10 (October 1, 2020): 3423–40. http://dx.doi.org/10.1175/jas-d-19-0173.1.

Full text

Abstract:

AbstractThe companion of this paper, Part I, discovered the characteristics of the rainfall progression in tropical-depression (TD)-type waves over the western North Pacific. In Part II, the large-scale controls on the convective rainfall progression have been investigated using the ERA-Interim data and the TRMM 3B42 precipitation-rate data during June–October from 1998 to 2013 through budgets of moist static energy (MSE) and moisture. A buildup of column-integrated MSE occurs in advance of deep convection, and an export of MSE occurs following deep convection, which is consistent with the MSE recharge–discharge paradigm. The MSE recharge–discharge is controlled by horizontal processes, whereby horizontal moisture advection causes net MSE import prior to deep convection. Such moistening by horizontal advection creates a moist midtroposphere, which helps destabilize the atmospheric column, leading to the development of deep convective rainfall. Following the heaviest rainfall, negative horizontal moisture advection dries the troposphere, inhibiting convection. Such moistening and drying processes explain why deep convection can develop without preceding shallow convection. The advection of moisture anomalies by the mean horizontal flow controls the tropospheric moistening and drying processes. As the TD-type waves propagate northwestward in coincidence with the northwestward environmental flow, the moisture, or convective rainfall, is phase locked to the waves. The critical role of the MSE import by horizontal advection in modulating the rainfall progression is supported by the anomalous gross moist stability (AGMS), where the lowest AGMS corresponds to the quickest increase in the precipitation rate prior to the rainfall maximum.

APA, Harvard, Vancouver, ISO, and other styles

24

Złotek, Urszula, Sławomir Lewicki, Anna Markiewicz, Urszula Szymanowska, and Anna Jakubczyk. "Effects of Drying Methods on Antioxidant, Anti-Inflammatory, and Anticancer Potentials of Phenolic Acids in Lovage Elicited by Jasmonic Acid and Yeast Extract." Antioxidants 10, no. 5 (April 24, 2021): 662. http://dx.doi.org/10.3390/antiox10050662.

Full text

Abstract:

The study presents the effect of drying methods (traditional, convection, microwave, and freeze-drying) on the content and bioactivity (determined as antioxidative, anti-inflammatory, and antiproliferative potential) of potentially bioavailable fractions of phenolic acids contained in lovage elicited with jasmonic acid (JA) and yeast extract (YE) and in untreated control leaves. The highest amount of syringic acid was recorded in the convectionally dried lovage samples, while ethanolic extracts from lyophilized lovage had the highest content of protocatechuic and caffeic acids. The drying method significantly influenced the tested properties only in some cases. The traditional drying resulted in lower antioxidant potential, while convectional drying caused a reduction of the lipoxygenase inhibition ability of the samples after simulated digestion. Samples containing the control and elicited lovage leaves dried with convectional and traditional methods exhibited the highest cytotoxicity against a prostate cancer epithelial cell line.

APA, Harvard, Vancouver, ISO, and other styles

25

Chayjan, R. A., and M. Kaveh. "Drying characteristics of eggplant (Solanum melongena L.) slices under microwave-convective drying." Research in Agricultural Engineering 62, No. 4 (November 28, 2016): 170–78. http://dx.doi.org/10.17221/13/2015-rae.

Full text

Abstract:

A laboratory scale microwave-convection dryer was used to dry the eggplant fruit, applying microwave power in the range of 270–630 W, air temperature in the range of 40–70°C and air velocity in the range of 0.5–1.7 m/s. Six mathematical models were used to predict the moisture ratio of eggplant fruit slices in thin layer drying. The results showed that the Midilli et al. model had supremacy in prediction of turnip slice drying behavior. Minimum and maximum values of effective moisture diffusivity (Deff) were 1.52 × 10–9 and 3.39 × 10–9 m2/s, respectively. Activation energy values of eggplant slices were found between 13.33 and 17.81 kJ/mol for 40°C to 70°C, respectively. The specific energy consumption for drying eggplant slices was calculated at the boundary of 86.47 and 194.37 MJ/kg. Furthermore, in the present study, the application of Artificial Neural Network (ANN) for predicting the drying rate and moisture ratio was investigated. Microwave power, drying air temperature, air velocity and drying time were considered as input parameters for the model.

APA, Harvard, Vancouver, ISO, and other styles

26

Doymaz, İbrahim, and Fergun Kocayigit. "Drying and Rehydration Behaviors of Convection Drying of Green Peas." Drying Technology 29, no. 11 (July 11, 2011): 1273–82. http://dx.doi.org/10.1080/07373937.2011.591713.

Full text

APA, Harvard, Vancouver, ISO, and other styles

27

Jolly, P. G. "Temperature Controlled Combined Microwave-Convection Drying." Journal of Microwave Power and Electromagnetic Energy 21, no. 2 (January 1986): 65–74. http://dx.doi.org/10.1080/08327823.1986.11687985.

Full text

APA, Harvard, Vancouver, ISO, and other styles

28

Faizal, Mir, and Stephen Peppin. "Convection in drying and freezing ground." Zeitschrift für angewandte Mathematik und Physik 66, no. 3 (August 7, 2014): 1071–80. http://dx.doi.org/10.1007/s00033-014-0447-0.

Full text

APA, Harvard, Vancouver, ISO, and other styles

29

Pal, U. S., and A. Chakraverty. "Thin layer convection-drying of mushrooms." Energy Conversion and Management 38, no. 2 (January 1997): 107–13. http://dx.doi.org/10.1016/0196-8904(96)00020-9.

Full text

APA, Harvard, Vancouver, ISO, and other styles

30

Poós, Tibor, and Evelin Varju. "Experimental investigation of pre-drying data for some medicinal herbs in forced convection." Thermal Science, no. 00 (2019): 465. http://dx.doi.org/10.2298/tsci190726465p.

Full text

Abstract:

The special active agent content of herbs makes them suitable for healing and health preservation. The key element in the processing of herbs and spices is drying. Before drying, the medicinal plants should be stored under appropriate conditions to avoid deterioration of quality where one of the possible methods is pre-drying with ambient air. This work defines the determination of main operational parameters at forced convection drying with ambient air like drying rate, volume decrease, maximum drying air velocity and porosity for various medicinal plants (common yarrow - Achillea collina, giant goldenrod - Solidago gigantea, wormwood - Artemisia, walnut leaf - Juglandis folium, wild carrot - Daucus carota). To determine the drying rate, a convective dryer was used where the average drying rate of common yarrow and wild carrot were the highest followed by giant goldenrod, walnut leaf and wormwood. Measurements were made on a pilot plant fluidized bed dryer to determine the volume decrease and the maximum drying air velocity. The volume decrease was determined as a function of time and moisture content. It was found that the maximum drying air velocity for each medicinal plant was between 1.8 and 2.2 m/s. In addition, for each herb the porosity was measured by an air pycnometer.

APA, Harvard, Vancouver, ISO, and other styles

31

Wright, J. S., R. Fu, and A. J. Heymsfield. "A statistical analysis of the influence of deep convection on water vapor variability in the tropical upper troposphere." Atmospheric Chemistry and Physics Discussions 9, no. 1 (February 9, 2009): 4035–79. http://dx.doi.org/10.5194/acpd-9-4035-2009.

Full text

Abstract:

Abstract. The factors that control the influence of deep convective detrainment on water vapor in the tropical upper troposphere are examined using observations from multiple satellites in conjunction with a trajectory model. Deep convection is confirmed to act primarily as a moisture source to the upper troposphere, modulated by the ambient relative humidity (RH). Convective detrainment provides strong moistening at low RH and offsets drying due to subsidence across a wide range of RH. Strong day-to-day moistening and drying takes place most frequently in relatively dry transition zones where the frequency of deep convective events is neither very high nor very low. Many of these strong moistening events can be directly attributed to detrainment from recent tropical convection. The temporal and spatial limits of the convective source are estimated to be about 36–48 h and 600–1500 km, respectively, consistent with the lifetimes of detrainment cirrus clouds. Larger amounts of detrained ice and smaller ice particle sizes are both associated with enhanced upper tropospheric moistening.

APA, Harvard, Vancouver, ISO, and other styles

32

Sobel, Adam H., and Gilles Bellon. "The Effect of Imposed Drying on Parameterized Deep Convection." Journal of the Atmospheric Sciences 66, no. 7 (July 1, 2009): 2085–96. http://dx.doi.org/10.1175/2008jas2926.1.

Full text

Abstract:

Abstract This paper examines the influence of imposed drying, intended to represent horizontal advection of dry air, on parameterized deep convection interacting with large-scale dynamics in a single-column model framework. Two single-column models, one based on the NASA Goddard Earth Observing System general circulation model version 5 (GEOS5) and the other developed by Bony and Emanuel, are run in weak temperature gradient mode. Drying is imposed by relaxation of the specific humidity field toward zero within a specified vertical layer. The strength of the drying is controlled by specifying either the relaxation time scale or the vertically integrated drying tendency; results are insensitive to which specification is used. The two models reach very different solutions for the same boundary conditions and model configuration. Even when adjustments to the boundary conditions and model parameters are made to render the precipitation rates similar, large differences in the profiles of relative humidity and large-scale vertical velocity persist. In both models, however, drying in the middle troposphere is more effective, per kg m−2 s−1 (or W m−2) of imposed drying, in suppressing precipitation than is drying in the lower troposphere. Even when compared at equal relaxation time (corresponding to weaker net drying in the middle than lower troposphere), middle-tropospheric drying is comparably effective to lower-tropospheric drying. Upper-tropospheric drying has a relatively small effect on precipitation, although large drying in the upper troposphere cannot be imposed as a steady state because of the lack of moisture there. Consistent with the other model differences, the gross moist stabilities of the two models are quite different and vary somewhat differently as a function of imposed drying, but in both models the gross moist stability increases as the drying is increased when it is less than around 30 W m−2 and located in the middle troposphere. For lower-tropospheric drying, the gross moist stability either decreases with increased drying or increases more slowly than for middle-tropospheric drying.

APA, Harvard, Vancouver, ISO, and other styles

33

Shamekh, Sara, Caroline Muller, Jean-Philippe Duvel, and Fabio D’Andrea. "How Do Ocean Warm Anomalies Favor the Aggregation of Deep Convective Clouds?" Journal of the Atmospheric Sciences 77, no. 11 (November 1, 2020): 3733–45. http://dx.doi.org/10.1175/jas-d-18-0369.1.

Full text

Abstract:

AbstractWe investigate the role of a warm sea surface temperature (SST) anomaly (hot spot of typically 3 to 5 K) on the aggregation of convection using cloud-resolving simulations in a nonrotating framework. It is well known that SST gradients can spatially organize convection. Even with uniform SST, the spontaneous self-aggregation of convection is possible above a critical SST (here 295 K), arising mainly from radiative feedbacks. We investigate how a circular hot spot helps organize convection, and how self-aggregation feedbacks modulate this organization. The hot spot significantly accelerates aggregation, particularly for warmer/larger hot spots, and extends the range of SSTs for which aggregation occurs; however, at cold SST (290 K) the aggregated cluster disaggregates if we remove the hot spot. A large convective instability over the hot spot leads to stronger convection and generates a large-scale circulation which forces the subsidence drying outside the hot spot. Indeed, convection over the hot spot brings the atmosphere toward a warmer temperature. The warmer temperatures are imprinted over the whole domain by gravity waves and subsidence warming. The initial transient warming and concomitant subsidence drying suppress convection outside the hot spot, thus driving the aggregation. The hot-spot-induced large-scale circulation can enforce the aggregation even without radiative feedbacks for hot spots sufficiently large/warm. The strength of the large-scale circulation, which defines the speed of aggregation, is a function of the hot spot fractional area. At equilibrium, once the aggregation is well established, the moist convective region with upward midtropospheric motion, centered over the hot spot, has an area surprisingly independent of the hot spot size.

APA, Harvard, Vancouver, ISO, and other styles

34

Aranda-González, Irma, David Betancur-Ancona, Luis Chel-Guerrero, and Yolanda Moguel-Ordóñez. "Effect of different drying methods on the composition of steviol glycosides in Stevia rebaudiana Bertoni leaves." International Agrophysics 31, no. 1 (January 1, 2017): 139–44. http://dx.doi.org/10.1515/intag-2016-0036.

Full text

Abstract:

Abstract Drying techniques can modify the composition of certain plant compounds. Therefore, the aim of the study was to assess the effect of different drying methods on steviol glycosides in Stevia rebaudiana Bertoni leaves. Four different drying methods were applied to Stevia rebaudiana Bertoni leaves, which were then subjected to aqueous extraction. Radiation or convection drying was performed in stoves at 60°C, whereas shade or sun drying methods were applied at 29.7°C and 70% of relative humidity. Stevioside, rebaudioside A, rebaudioside B, rebaudioside C, rebaudioside D, dulcoside A, and steviolbioside were quantified by a validated HPLC method. Among steviol glycosides, the content (g 100 g−1 dry basis) of stevioside, rebaudioside A, rebaudioside B, and rebaudioside C varied according to the drying method. The total glycoside content was higher in sun-dried samples, with no significant differences compared to shade or convection drying, whereas radiation drying adversely affected the content of rebaudioside A and rebaudioside C (p <0.01) and was therefore a method lowering total glycoside content. The effect of the different drying methods was also reflected in the proportion of the sweetener profile. Convection drying could be suitable for modern food processing industries while shadow or sun drying may be a low-cost alternative for farmers.

APA, Harvard, Vancouver, ISO, and other styles

35

Wojdyło, Aneta, Krzysztof Lech, and Paulina Nowicka. "Effects of Different Drying Methods on the Retention of Bioactive Compounds, On-Line Antioxidant Capacity and Color of the Novel Snack from Red-Fleshed Apples." Molecules 25, no. 23 (November 25, 2020): 5521. http://dx.doi.org/10.3390/molecules25235521.

Full text

Abstract:

The aim of this study was to determine the effect of different drying methods: convective (at 50, 60, 70 °C), vacuum-microwave (at 120, 240, 360, 480 W and 360 W with reduction to 120 W) and hybrid (convective pre-drying at 50, 60, 70 °C followed by vacuum-microwave drying at 120 W) on the quality parameters of novel red-fleshed apple fruit snacks (RFAs), such as phenolics, on-line antioxidant capacity, water activity and color. Drying kinetics, including a temperature profile of dried material, and modified Page model were determined. Freeze-drying was used as a control method. The highest content of bioactive compounds in the samples was retained following freeze-drying, then hybrid, vacuum-microwave and finally convection drying. The antioxidant capacity measured by on-line 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS), identified anthocyanins, flavan-3-ols and phenolic acid as the main compounds responsible for this activity. Unfavorable changes in color, formation of hydroxymethylfurfural (HMF) and degradation of polyphenolics were noted along with increasing drying temperature and magnetron power. The red-fleshed apple snacks are a promising high-quality dehydrated food product belonging to functional foods category.

APA, Harvard, Vancouver, ISO, and other styles

36

Jou, Rong Yuan. "Heat and Mass Transfer Measurements for Bio-Substrate Drying Processes." Applied Mechanics and Materials 365-366 (August 2013): 595–601. http://dx.doi.org/10.4028/www.scientific.net/amm.365-366.595.

Full text

Abstract:

The complex process of heat and mass transfer in bio-substrates during convection, vacuum, and thermohygrostat drying was studied. Changes in temperature and moisture content at the center of the wet material were measured before and after the experiment in order to calculate the drying rate (%/h). In the case of convection drying, the inverter frequency within the wind tunnel was set at 10, 20, and 30 Hz (velocities of 2.2, 4, and 6 m/s, respectively). Measurements were then made at 10 and 20 Hz, with temperatures at 50 and 60°C. In the case of vacuum drying, the chamber pressure was set at 0.4, 4.2, and 92 Torr. The thermohygrostat was set at 50°C with humidity levels at 30, 40, and 50%. In conclusion, thermohygrostat is more effective because of the controlled environment, and that drying rate is increased with lower wind velocities and chamber pressures for convection and vacuum drying respectively.

APA, Harvard, Vancouver, ISO, and other styles

37

Sahdev, Ravinder Kumar. "Convective heat transfer coefficient for indoor forced convection drying of vermicelli." IOSR Journal of Engineering 02, no. 06 (June 2012): 1282–90. http://dx.doi.org/10.9790/3021-026112821290.

Full text

APA, Harvard, Vancouver, ISO, and other styles

38

Łyczko, Jacek, Klaudiusz Jałoszyński, Mariusz Surma, Klaudia Masztalerz, and Antoni Szumny. "HS-SPME Analysis of True Lavender (Lavandula angustifolia Mill.) Leaves Treated by Various Drying Methods." Molecules 24, no. 4 (February 20, 2019): 764. http://dx.doi.org/10.3390/molecules24040764.

Full text

Abstract:

True lavender (Lavandula angustifolia Mill.) is a widely used flavoring and medicinal plant, which strong aroma is mainly composed of linalool and linalyl acetate. The most valuable parts of the plant are the flowers, however leaves are also abundant in volatile constituents. One of the main factors responsible for its quality is the preservation procedure, which usually comes down to a drying process. For this reason an attempt to verify the influence of various drying methods (convective drying, vacuum-microwave drying and combined convection pre-drying with vacuum-microwave finishing drying) on the quality of true lavender leaves was carried out by determination of the volatile constituents profile by solid-phase microextraction (SPME) coupled with GC-MS technique. Total essential oil (EO) content was also verified. The study has revealed that the optimal drying method is strongly dependent on the purpose of the product. For flavoring properties convective drying at 60 °C is the most optimal method, while the best for preserving the highest amount of EO is vacuum-microwave drying at 480 W. Furthermore, SPME analysis had shown that drying may increase the value of true lavender leaves by significantly affecting the linalool to linalyl acetate to camphor ratio in the volatile profile.

APA, Harvard, Vancouver, ISO, and other styles

39

Kwaśnica, Andrzej, Natalia Pachura, Klaudia Masztalerz, Adam Figiel, Aleksandra Zimmer, Robert Kupczyński, Katarzyna Wujcikowska, Angel A. Carbonell-Barrachina, Antoni Szumny, and Henryk Różański. "Volatile Composition and Sensory Properties as Quality Attributes of Fresh and Dried Hemp Flowers (Cannabis sativa L.)." Foods 9, no. 8 (August 13, 2020): 1118. http://dx.doi.org/10.3390/foods9081118.

Full text

Abstract:

Flowers of hemp (Cannabis sativa L.) are widely used in cosmetics, food, and in the pharmaceutical industry. The drying process plays a key role in retention of aroma and also in the quality of products. Seven variants of hemp flower drying, including convection drying (CD), vacuum–microwave drying (VMD), and combined drying consisting of convective pre-drying followed by vacuum–microwave finishing drying (CPD-VMFD) were checked in this study. For each process, we applied the two-term model. Dried material was submitted to color and chromatographical assessments. Analyses of obtained essential oil showed the presence of 93 volatile compounds, predominantly β-myrcene, limonene, and β-(E)-caryophyllene, as well as α-humulene. Application of 240 W during VMD and 50 °C during CD gave the highest retention of aroma compounds, amounting to 85 and 76%, respectively, but with huge color changes. Additionally, sensory analysis proved that drying with a microwave power of 240 W provides a product most similar to fresh material.

APA, Harvard, Vancouver, ISO, and other styles

40

Suresh, Munusamy, Ponnusamy Palanisamy, and Kumar Senthil. "Drying of mint leaves in forced convection solar dryer." Thermal Science 23, no. 6 Part B (2019): 3941–49. http://dx.doi.org/10.2298/tsci171230303s.

Full text

Abstract:

In this present work, performance study on drying mint leaves under the metrological conditions. Intensity of radiation falls on the absorber plate which transfers heat to forced air-flow inside the galvanized iron tube. Drying experiment carried out with 1 kg of mint leaves taken for drying process under the different mass-flow rate of 0.75 m/s and 1.25 m/s in serpentine flow of air. Performance of the collector and drying efficiency were 30.33% and 1.63% in first day at 0.75 m/s mass-flow rate and in the second day collector, the drying efficiency were 29.41% and 1.89% at the mass-flow rate of 1.25 m/s. The mass-flow rate of air decreased with increasing collector and drying efficiency.

APA, Harvard, Vancouver, ISO, and other styles

41

Wright, J. S., R. Fu, and A. J. Heymsfield. "A statistical analysis of the influence of deep convection on water vapor variability in the tropical upper troposphere." Atmospheric Chemistry and Physics 9, no. 15 (August 12, 2009): 5847–64. http://dx.doi.org/10.5194/acp-9-5847-2009.

Full text

Abstract:

Abstract. The factors that control the influence of deep convective detrainment on water vapor in the tropical upper troposphere are examined using observations from multiple satellites in conjunction with a trajectory model. Deep convection is confirmed to act primarily as a moisture source to the upper troposphere, modulated by the ambient relative humidity (RH). Convective detrainment provides strong moistening at low RH and offsets drying due to subsidence across a wide range of RH. Strong day-to-day moistening and drying takes place most frequently in relatively dry transition zones, where between 0.01% and 0.1% of Tropical Rainfall Measuring Mission Precipitation Radar observations indicate active convection. Many of these strong moistening events in the tropics can be directly attributed to detrainment from recent tropical convection, while others in the subtropics appear to be related to stratosphere-troposphere exchange. The temporal and spatial limits of the convective source are estimated to be about 36–48 h and 600–1500 km, respectively, consistent with the lifetimes of detrainment cirrus clouds. Larger amounts of detrained ice are associated with enhanced upper tropospheric moistening in both absolute and relative terms. In particular, an increase in ice water content of approximately 400% corresponds to a 10–90% increase in the likelihood of moistening and a 30–50% increase in the magnitude of moistening.

APA, Harvard, Vancouver, ISO, and other styles

42

Leguizamón Delgado, Maria Alejandra, Alba Lucía Duque Cifuentes, and Victor Dumar Quintero Castaño. "Physico-chemical and sensory evaluation of a mango-based fruit bar." DYNA 86, no. 210 (July 1, 2019): 276–83. http://dx.doi.org/10.15446/dyna.v86n210.72950.

Full text

Abstract:

The objective of this work was the evaluation of a mango-based fruit bar. Tommy Atkins pulp and mango peel physicochemically were characterized. Three drying methods were compared: lyophilization, convection drying, and microwave assisted convection drying. Subsequently six formulations were made varying the amount of pectin from 0.5 to 2.5%, water, inulin, glycerol and ascorbic acid. The results obtained showed that microwave-assisted convection drying at 40 ° C for the shell showed a higher concentration of fiber. Two formulations were selected for physicochemical, microbiological and sensory analysis. Formulation D with a higher percentage of pectin was more widely accepted. The values obtained from vitamin C and total phenolic compounds show that the formulation of a fruit bar is feasible, taking advantage of the shell mainly as a raw material for foods with functional characteristics.

APA, Harvard, Vancouver, ISO, and other styles

43

Kumar, Mahesh. "EXPERIMENTAL FORCED SOLAR THIN LAYER GINGER DRYING." Facta Universitatis, Series: Mechanical Engineering 14, no. 1 (April 1, 2016): 101. http://dx.doi.org/10.22190/fume1601101k.

Full text

Abstract:

In this research paper, the convective and the evaporative heat transfer coefficients of ginger (zingiber officinale) drying in an indirect solar cabinet dryer under the induced forced convection mode is presented. Experiments were conducted during the month of March 2015 under the climatic conditions of Hisar, India (29°5’5”N latitude and 75°45’55”E longitude). The experimental data obtained for solar drying of a constant ginger mass of 150 g has been used to determine constants ‘C’ and ‘n’ in the Nusselt number expression using linear regression analysis; consequently, the convective and the evaporative heat transfer coefficients have been evaluated. The average value of constants ‘C’ and ‘n’ were evaluated as 0.999 and 0.318, respectively. The average values of the convective and the evaporative heat transfer coefficients were found to be 3.95 W/m2 °C and 160.47 W/m2 °C, respectively, for the given mass samples of ginger. The average collector efficiency was observed to be 14.5%. The experimental error in terms of percentage uncertainty was found to be 20.87%.

APA, Harvard, Vancouver, ISO, and other styles

44

Grandpeix, Jean-Yves, Jean-Philippe Lafore, and Frédérique Cheruy. "A Density Current Parameterization Coupled with Emanuel’s Convection Scheme. Part II: 1D Simulations." Journal of the Atmospheric Sciences 67, no. 4 (April 1, 2010): 898–922. http://dx.doi.org/10.1175/2009jas3045.1.

Full text

Abstract:

Abstract The density current parameterization coupled with Emanuel’s convection scheme, described in Part I of this series of papers, is tested in a single-column framework for continental and maritime convective systems. The case definitions and reference simulations are provided by cloud-resolving models (CRMs). For both cases, the wake scheme yields cold pools with temperature and humidity differences relative to the environment in reasonable agreement with observations (with wake depth on the order of 2 km over land and 1 km over ocean). The coupling with the convection scheme yields convective heating, drying, and precipitation similar to those simulated by the CRM. Thus, the representation of the action of the wakes on convection in terms of available lifting energy (ALE) and available lifting power (ALP) appears satisfactory. The sensitivity of the wake–convection system to the basic parameters of the parameterization is widely explored. A range of values for each parameter is recommended to help with implementing the scheme in a full-fledged general circulation model.

APA, Harvard, Vancouver, ISO, and other styles

45

VAIDYA, S. S., and S. S. SINGH. "Sensitivity of convective rainfall to the adjustment parameters in the Betts-Miller scheme." MAUSAM 47, no. 4 (December 14, 2021): 395–402. http://dx.doi.org/10.54302/mausam.v47i4.3759.

Full text

Abstract:

ABSTACT. Three numerical experiments are carried out to study the sensitivity of the convective rain fall to the adjustment parameters used in the Betts-Miller scheme of cumulus convection. The results of the numerical experiments indicate that the convective rainfall has considerable sensitivity to saturation pressure departure value (S) whereas the impact of stability weight (W) on the convective rainfall is marginal. The limiting S values are found to produce drying of the column.

APA, Harvard, Vancouver, ISO, and other styles

46

Tönsmann, Max, Philip Scharfer, and Wilhelm Schabel. "Transient Three-Dimensional Flow Field Measurements by Means of 3D µPTV in Drying Poly(Vinyl Acetate)-Methanol Thin Films Subject to Short-Scale Marangoni Instabilities." Polymers 13, no. 8 (April 10, 2021): 1223. http://dx.doi.org/10.3390/polym13081223.

Full text

Abstract:

Convective Marangoni instabilities in drying polymer films may induce surface deformations, which persist in the dry film, deteriorating product performance. While theoretic stability analyses are abundantly available, experimental data are scarce. We report transient three-dimensional flow field measurements in thin poly(vinyl acetate)-methanol films, drying under ambient conditions with several films exhibiting short-scale Marangoni convection cells. An initial assessment of the upper limit of thermal and solutal Marangoni numbers reveals that the solutal effect is likely to be the dominant cause for the observed instabilities.

APA, Harvard, Vancouver, ISO, and other styles

47

Meyer, Michael, and Kristin Trommer. "Soft Collagen-Gelatine Sponges by Convection Drying." Brazilian Archives of Biology and Technology 58, no. 1 (August 1, 2014): 109–17. http://dx.doi.org/10.1590/s1516-8913201400139.

Full text

APA, Harvard, Vancouver, ISO, and other styles

48

Pabis, Stanisław. "Theoretical models of vegetable drying by convection." Transport in Porous Media 66, no. 1-2 (January 24, 2007): 77–87. http://dx.doi.org/10.1007/s11242-006-9023-1.

Full text

APA, Harvard, Vancouver, ISO, and other styles

49

Bala, B. K., and J. L. Woods. "Optimization of natural-convection, solar drying systems." Energy 20, no. 4 (April 1995): 285–94. http://dx.doi.org/10.1016/0360-5442(94)00083-f.

Full text

APA, Harvard, Vancouver, ISO, and other styles

50

Martynenko, Alex, Tess Astatkie, and Thijs Defraeye. "The role of convection in electrohydrodynamic drying." Journal of Food Engineering 271 (April 2020): 109777. http://dx.doi.org/10.1016/j.jfoodeng.2019.109777.

Full text

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Convection drying'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles