EVALUATION OF HEAT AND MASS TRANSFER COEFFICIENTS AT BEETROOT-AIR INTERFACE DURING CONVECTIVE DRYING

2020 ◽  
Vol 8 (4) ◽  
pp. 303-319
Author(s):  
Dasore Abhishek ◽  
K. Ramakrishna ◽  
B. Kiran Naik
Keyword(s):  
Mass Transfer ◽  
Heat And Mass Transfer ◽  
Convective Drying ◽  
Transfer Coefficients ◽  
Mass Transfer Coefficients ◽  
Air Interface

Pear Drying: Thermodynamics Studies and Coefficients of Convective Heat and Mass Transfer

2013 ◽  
Vol 9 (4) ◽  
pp. 365-374 ◽  
Author(s):  
Alexandre Navarro da Silva ◽  
Jane Sélia dos Reis Coimbra ◽  
Fernando Mendes Botelho ◽  
Moysés Naves de Moraes ◽  
Janaína Teles de Faria ◽  
...  
Keyword(s):  
Mass Transfer ◽  
Heat And Mass Transfer ◽  
Convective Drying ◽  
Pyrus Pyrifolia ◽  
Drying Process ◽  
Transfer Coefficients ◽  
Mass Transfer Coefficients ◽  
Drying Behavior ◽  
Forced Air ◽  
Cylindrical Samples

AbstractThe objective of this work was to study the convective drying process used for cylindrical samples of two different pear varieties, one originating from Europe (Pyrus communis) and the other from Asia (Pyrus pyrifolia), submitted to two blanching treatments, as well as determine some coefficients referring to heat and mass transfer and thermodynamic parameters of the process, being: enthalpy (ΔH*), entropy (ΔS*) and Gibbs energy of activation (ΔG*). All samples were dried in a forced air oven at temperatures of (62, 76, 84 and 92)°C until reaching a constant mass. The heat and mass transfer coefficients referring to the constant and falling-rate drying periods were obtained by adjusting the experimental data to wet bulb temperature and liquid diffusion models, respectively. The heat and mass transfer coefficients varied linearly with temperature. Blanching altered the drying behavior of the two varieties in relation to the non-blanched samples, mainly at the elevated drying temperatures of 84°C and 92°C. ΔH* and ΔS* decreased while ΔG* increased with the elevation of drying temperature; therefore, it was possible to verify that variation in the diffusion process in pears during drying is dependent on energetic contributions of the environment.

Numerical Simulation of Heat and Mass Transfer Enhancement in Absorption Process With Double-Side Film-Inversion

2008 ◽  
Author(s):  
Ya-Ping Chen ◽  
Chen-Jie Shi ◽  
Ming-Heng Shi ◽  
Chen-Min Ling
Keyword(s):  
Mass Transfer ◽  
Heat And Mass Transfer ◽  
Vertical Plane ◽  
Mathematic Model ◽  
Absorption Process ◽  
Transfer Coefficients ◽  
Mass Transfer Coefficients ◽  
Plane Plate ◽  
Before And After ◽  
Calculation Results

Film-inversion is an effective way recently developed to enhance heat and mass transfer in absorbers. However, only one-side of round or rectangular tube i.e. half of the total heat transfer area is used to form film-inverting configuration in the published literature. The paper presents a double-side film-inverting scheme, which consists of two plate bundles and a set of comb shaped conjunction guiders between them for leading solution film from both-sides of each couple of the upper plate bundle to the opposite sides of the bottom ones. A two-scale crosswise corrugation plate bundle, which has vertical large corrugations and horizontal small ones, is suggested instead of the plane plate bundle. The horizontal small corrugation can make the film turbulent and film distribution uniform before and after inversion with surface tension effect, thus increasing the heat and mass transfer coefficients of the absorption process. A mathematic model for heat and mass transfer in absorption process with aqueous Li-Br solution falling film-inverting on two sequential vertical plane plates was established and solved numerically. The distributions of dimensionless velocity, temperature and concentration of liquid film profile before and after film-inverting were obtained. The influence of the number of inversion on heat and mass transfer characteristics was analyzed. The calculation results show that the heat and mass transfer coefficients of the once-film-inverting scheme have about 58% and 73% increment respectively over these of the none film-inverting scheme.

scholarly journals Experimental study of heat and mass transfer coefficients at heat recovery of steam-gas flow in the torch of drops of mechanical nozzle

2015 ◽  
Vol 6 (8(78)) ◽  
pp. 50
Author(s):  
Артур Юрьевич Рачинский ◽  
Михаил Константинович Безродный ◽  
Николай Никифорович Голияд ◽  
Петр Алексеевич Барабаш
Keyword(s):  
Mass Transfer ◽  
Experimental Study ◽  
Heat And Mass Transfer ◽  
Heat Recovery ◽  
Gas Flow ◽  
Transfer Coefficients ◽  
Mass Transfer Coefficients
Sign in / Sign up

Export Citation Format

Share Document