Determination of thermal conductivity, specific heat and thermal diffusivity of albacore (Thunnus alalunga)

1989 ◽  
Vol 189 (6) ◽  
pp. 525-529 ◽  
Author(s):  
Ricardo I. Perez-Mart�n ◽  
Jose M. Gallardo ◽  
Julio R. Banga ◽  
J. Casares
Keyword(s):  
Thermal Conductivity ◽  
Thermal Diffusivity ◽  
Specific Heat ◽  
Thunnus Alalunga

scholarly journals Determination of thermophysical properties of cupuassu (Theobroma grandiflorum) dry almonds

2021 ◽  
Vol 7 (2) ◽  
Author(s):  
Elisa Santana Cunha ◽  
Geovana Pires Araújo Lima ◽  
Jorge Henrique Oliveira Sales ◽  
Elizama Aguiar de Oliveira
Keyword(s):  
Thermal Conductivity ◽  
Activation Energy ◽  
Thermal Diffusivity ◽  
Specific Heat ◽  
Thermophysical Properties ◽  
Effective Diffusivity ◽  
Theobroma Grandiflorum

In comparison to cocoa, little has been reported on the drying of cupuassu almonds that can be used to produce cupulate, a chocolate type product. Thus, in this study thermophysical properties of cupuassu dry almonds (moisture = 9.68 % d.b.) were determined as: thermal conductivity (k) of 0.14 kW/(m.K), specific heat (cp) of 2.86 kJ/(kg.K), thermal diffusivity (?) of 4.8·10-5 m²/s, effective diffusivity (Deff) of 9.94·10-10 - 6.29·10-10 m²/s and activation energy (Ea) of 14.90 kJ/mol. These results showed a similarity of values between cupuassu and cocoa and allows to perform more specific studies for the development of dryers for the cupuassu almonds.

scholarly journals DETERMINATION OF THERMAL PROPERTIES OF COFFEE BEANS AT DIFFERENT DEGREES OF ROASTING

2018 ◽  
Vol 13 (4) ◽  
pp. 498
Author(s):  
Danilo Barbosa Cardoso ◽  
Ednilton Tavares de Andrade ◽  
Renso Alfredo Aragón Calderón ◽  
Mariane Helena Sanches Rabelo ◽  
Camila De Almeida Dias ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Thermal Properties ◽  
Thermal Diffusivity ◽  
Specific Heat ◽  
Infinite Cylinder ◽  
Element Analysis ◽  
Heating Source ◽  
Mixing Method ◽  
Cylinder Method

<p>The aim of this study was to determine the main thermal properties of the granular mass of coffee (specific heat, thermal conductivity, and thermal diffusivity) for different degrees of roasting, as well as to model and simulate thermal conductivity at different degrees of roasting. For determination of specific heat, the mixing method was used, and for thermal conductivity, the theoretically infinite cylinder method with a central heating source. Thermal diffusivity was simulated algebraically using the results of the properties cited above and of the apparent specific mass of the product. Thermal conductivity was also simulated and optimized through finite element analysis software. At darker roasting, there was an increase in specific heat and a reduction in thermal conductivity and thermal diffusivity. Comparing thermal conductivity determined in relation to simulated and optimized conductivity, the mean relative error was 1.02%, on average.</p>

scholarly journals Determination of Some Selected Thermal Properties of Pumpkin Seeds (Cucurbita pepo)

2021 ◽  
Vol 25 (4) ◽  
pp. 599-604
Author(s):  
M.O. Sunmonu ◽  
M.M. Odewole ◽  
O.A. Adeyinka ◽  
M.S. Sanusi ◽  
S.O. Musa
Keyword(s):  
Thermal Conductivity ◽  
Thermal Properties ◽  
Thermal Diffusivity ◽  
Moisture Content ◽  
Specific Heat ◽  
Average Moisture Content ◽  
Pumpkin Seed ◽  
C Value ◽  
Pumpkin Seeds

In this study, some selected thermal properties (specific heat, thermal conductivity and thermal diffusivity) in the moisture content range of 5.0-5.6% or green and 4.80 – 5.20% for white varieties of pumpkin seeds were determined. The specific heat was measured using mixture method while the thermal conductivity was measured by transient technique using the heat line source. The green pumpkin seed has average moisture content of 5.2% higher than moisture content of white pumpkin seed of average 4.8%. The average specific heat values of green pumpkin seed are 6.171kJ/kgK and white pumpkin seed 4.327kJ/kgK. The thermal conductivity values for white pumpkin seed ranged from 0.074 to 0.288 W/m°C while that for green pumpkin seed ranged from 0.079 to 0.433 W/m°C. The thermal diffusivity values for green pumpkin ranged from 0.0011 to 0.06 m2/s while that for white pumpkin seed ranged from 0.01 to 0.06 m2/s. It was concluded that the higher the moisture content (5.2%) the higher the value of specific heat of seed (6.171kJ/kgK). It can also be concluded that the thermal conductivity (0.079 to 0.433 W/m°C) value is higher with high moisture content (5.2%).

scholarly journals Studies on the Natural Smouldering of Cigarettes: III. Determination of the Thermal Properties of Tobacco Shreds Packed in Columns

1979 ◽  
Vol 10 (1) ◽  
pp. 17-23 ◽  
Author(s):  
Motohiko Muramatsu ◽  
Setsuko Umemura ◽  
Takashi Okada
Keyword(s):  
Thermal Conductivity ◽  
Thermal Diffusivity ◽  
Specific Heat ◽  
Effective Thermal Conductivity ◽  
Packing Fraction ◽  
Transient Hot Wire ◽  
Specific Heats ◽  
Wire Method ◽  
Transfer Problems

Abstract The values of effective thermal conductivity, specific heat and thermal diffusivity of various kinds of tobacco shreds, which are necessary for the solution of heat transfer problems of a smouldering cigarette, were determined. Effective thermal conductivity of tobacco shred packed into simulated cigarette columns was measured by a transient hot-wire method as a function of packing fraction at conditions of 20°C and 60 % relative humidity. Specific heat was measured with the aid of a differential scanning calorimeter (DSC). The thermal diffusivity was obtained from the values of effective thermal conductivity, specific heat and packing density. Effective thermal conductivity increased with increasing packing fraction (1 - e) and was uniformly expressed as a function of the total void fraction (et) inside the column regardless of tobacco types and stalk positions, whereas thermal diffusivity decreased with the packing fraction. At the same packing fraction, bright shreds produced higher values of effective thermal conductivity as well as higher specific heats (although specific heat was independent of the packing fraction) but had lower thermal diffusivity values than Burley and Matsukawa shreds.

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