in this research the drying of four kinds of vegetables was investigated in a vacuum dryer. the effect of temperature on drying rate of samples at various temperatures (30, 35 and 45 °c) was studied. six thin-layer drying models were fitted to drying data and suitable model was selected from them. then effective moisture diffusivity and activation energy of samples were calculated. the diffusio...

Convective hot air drying of potato slabs and the effects of drying air temperature and slab thickness have been investigated using a batch tray dryer. The temperature of drying chamber varied in four levels (50, 60, 70 and 80°C) and the slab thickness changed in three levels (0.5, 1 and 1.5 m). For the prediction of effective moisture diffusivity (D ), the conventional Fick’s diffusion model w...

the moist sample shrinks during drying and the non-uniformity shrinkage involves stresses in the body. the aim of the present work is simulating deformations and drying-induced stresses of carrot slice during a convective drying. the effect of shrinkage on the heat and mass transfer profiles were considered. non-constant physical and thermal properties were also incorporated in the model and th...

This paper describes an experimental investigation of the drying behavior and conditions of rosehip in a convective cyclone-type dryer. Drying experiments were conducted at air inlet temperatures of 50, 60 and 70 o C and air velocities of 0.5, 1 and 1.5 ms. The parametric values obtained from the experiments were fitted to the Newton mathematical models. Consequently, the drying model developed...

Drying experiments have been carried out with model soils made of different pastes filling granular packings. A detailed information concerning the time evolution of the water saturation distribution inside the sample was obtained from magnetic resonance imaging measurements. This study makes it possible to understand the physical origin of the drying characteristics of these materials. The dry...

in this research, the effect of ultrasound-osmotic dehydration process in different conditions on the drying kinetics parameters of rhubarb was investigated. before dying process, rhubarb samples were placed in contact of ultrasound-osmotic pretreatment and then dried by convection hot air dryer equipped with circulated fan. the results showed that using osmotic pretreatment at 40% sucrose solu...

Drying kinetics of coir pith was studied and the properties of compressed coir pith discs were analyzed. Coir pith particles were oven dried in the range of temperatures from 100 to 240 °C and the rehydration ability of compressed coir pith was evaluated by finding the volume expansion. The optimum drying temperature was found to be 140 °C. Hot air drying was carried out to examine the drying k...

In this study, the drying kinetics of granular nylon-6 has been investigated. Single particle drying experiments were carried out in a magnetic suspension balance (MSB) using dry air as drying agent. The comparison of measured and simulated data using Vrentas-Duda diffusion model shows a satisfactory prediction of mean particle moisture content and drying rates. The Flory-Huggins model predicts...

Spray drying is a commonly used method of drying a liquid feed through a hot gas. This study aims to obtain the empirical model of the spray drying process of full cream milk using a nozzle atomizer spray dryer, Lab-Plant SD 05 Laboratory Scale Spray Dryer. Inlet air temperature was chosen as the manipulated variable and outlet air temperature was the controlled variable. No disturbance was con...

in this work, a hybrid gmdh–neural network model was developed in order to predict the moisture content of papaya slices during hot air drying in a cabinet dryer. for this purpose, parameters including drying time, slices thickness and drying temperature were considered as the inputs and the amount of moisture ratio (mr) was estimated as the output. exactly 50% of the data points were used for ...