scholarly journals THERMAL PROPERTIES OF MALAYSIAN COHESIVE SOILS

2016 ◽  
Vol 78 (8-5) ◽  
Author(s):  
Adriana Amaludin ◽  
Aminaton Marto ◽  
Muhd. Hatta M. Satar ◽  
Hassanel Amaludin ◽  
Salinah Dullah
Keyword(s):  
Thermal Conductivity ◽  
Thermal Properties ◽  
Moisture Content ◽  
Specific Heat ◽  
Cohesive Soil ◽  
Linear Increase ◽  
Thermal Resistivity ◽  
Soil Matrix ◽  
Volumetric Specific Heat ◽  
Shallow Geothermal Energy

The thermal properties of soils surrounding energy piles are required for the efficient and optimal design of shallow geothermal energy pile systems. In this study, the thermal conductivity, thermal resistivity and volumetric specific heat of two types of Malaysian cohesive soil were obtained through a series of laboratory experiments using a thermal needle probe. This study was conducted to determine the effect of moisture content on the thermal conductivity, thermal resistivity and volumetric specific heat values of the cohesive soil at a given value of soil density. For soils with low to medium moisture content, a linear increase in the thermal conductivity and volumetric heat capacity was observed as the moisture content gradually increased, while the thermal resistivity values of the soil had decreased. Meanwhile, for soils with high moisture content, the thermal conductivity was observed to have decreased, and a marked increase was seen in the thermal resistivity. This is due to the disruption of the thermal flow continuity in the soil matrix with the presence of moisture in the soil which adversely affects the thermal conductivity

Thermal Properties of Selected Timbers

2014 ◽  
Vol 982 ◽  
pp. 100-103 ◽  
Author(s):  
Dana Koňáková ◽  
Monika Čáchová ◽  
Eva Vejmelková ◽  
Martin Keppert ◽  
Robert Černý
Keyword(s):  
Thermal Conductivity ◽  
Heat Capacity ◽  
Thermal Properties ◽  
Moisture Content ◽  
Specific Heat ◽  
Heat Transport ◽  
Specific Heat Capacity ◽  
Open Porosity ◽  
Building Structures ◽  
The Difference

This article deals with thermal properties of selected kinds of timber. Wood, generally, is one of often used natural materials in building structures. For our research, woods were selected according to frequency of utilization in civil engineering branch. Four different timbers were chosen, and experimental determinations of their properties were performed. Basic physical properties as well as thermal properties belong among studied characteristics. From achieved results, it is obvious, that the bulk density of studied wood ranges between 373 kg m-3 and 649 kg m-3, the open porosity differ by 13%. Regarding thermal properties, values of the thermal conductivity as well as the specific heat capacity are influenced mainly by the open porosity and moisture content. The thermal conductivity in dry state varies by about 31% while in the case of the specific heat capacity the difference is about 19%. Obtained date will be used in the mathematical analysis of heat transport in building structures.

scholarly journals Effect of moisture content on the thermal properties of Horse-Eye Bean seeds relevant to its processing

2020 ◽  
Vol 45 (4) ◽  
pp. 71-80
Author(s):  
Ide Ejike ◽  
Ike Oluka ◽  
Eze Chukwuka
Keyword(s):  
Thermal Conductivity ◽  
Regression Analysis ◽  
Thermal Properties ◽  
Thermal Diffusivity ◽  
Moisture Content ◽  
Specific Heat ◽  
Bulk Density ◽  
Food Processing ◽  
Positive Relationship ◽  
Measured Specific Heat

The specific heat, thermal conductivity and thermal diffusivity of the Horse-Eye bean (Mucuna sloanei) were determined as a function of moisture content using the method reported by A.O.A.C (2000). The sample varieties used were the Big Sized and the Small Sized Horse-Eye bean. The specific heat and the thermal conductivity were measured using a Bomb Calorimeter. The thermal diffusivity was calculated from the measured specific heat, thermal conductivity and bulk density of the samples. Within the moisture range of 10.5% to 16.87% (b.b), the specific heat, thermal conductivity and thermal diffusivity varied with the moisture content. Results showed that the specific heat, thermal conductivity and thermal diffusivity of the Horse-Eye bean seeds ranged from 116.76 to 203.29 kJ/kgK; 21.07 to 32.23 W/moC; and 3.12 x 10-7 to 9.19 x 10-7 m 2 /s, for the Big Sized varieties, and 112.06 to 194.61 kJ/kgK; 19.85 to 24.08 W/moC; and 3.05 x 10-7 to 6.71 x 10-7 m 2 /s, for the Small Sized varieties as the moisture content increases from 10.5% to 16.87%. Regression analysis were also carried out on the thermal properties of the Horse-Eye bean varieties and moisture content, and there was positive relationship between the parameters. There were significant effects of moisture content (p < 0.05) on all the parameters conducted. The findings and the data generated will create an impact in the food processing industries for Horse-Eye bean.

Moisture-dependent Physical and Thermal Properties of Sericea Lespedeza Seeds

2019 ◽  
Vol 35 (3) ◽  
pp. 389-397
Author(s):  
Ajit K Mahapatra ◽  
Daniel E Ekefre ◽  
Hema L Degala ◽  
Somashekhar M Punnuri ◽  
Thomas H Terrill
Keyword(s):  
Thermal Conductivity ◽  
Thermal Properties ◽  
Moisture Content ◽  
Specific Heat ◽  
Geometric Mean ◽  
Seed Mass ◽  
Angle Of Repose ◽  
Engineering Properties ◽  
Sericea Lespedeza ◽  
Mean Diameter

Abstract. The bioactivity of Sericea lespedeza (SL) condensed tannins, including suppression of gastrointestinal nematodes, has contributed to a surge in interest of use of this plant in livestock production systems worldwide. Physical and thermal properties of SL seeds (AU Grazer™ and Serala cultivars) were determined as a function of moisture content for a moisture range from 8.57% to 26.53%, wet basis. The length, width, arithmetic mean diameter, geometric mean diameter, surface area, volume, and 1000 seed mass of both the seeds increased as the moisture content increased. Bulk density and unit density decreased as the moisture content increased. The sphericity of SL seeds decreased with increasing moisture content. Serala seeds were characterized by a higher aspect ratio than AU Grazer™. The angle of repose of SL seeds increased, while the compressibility index decreased in the moisture range. For color, the L* values of SL seeds decreased while the a* values increased with the increase in moisture content. A decrease in the b* values was insignificant. The thermal conductivity and specific heat of SL seeds decreased, whereas, thermal diffusivity increased as the moisture content of SL seeds increased. Serala seeds were characterized by higher values of thermal conductivity and volumetric specific heat than AU Grazer™. Keywords: Engineering properties, Moisture content, Physical properties, Seeds, Thermal properties.

scholarly journals Thermal properties of soursop seeds and kernels

2017 ◽  
Vol 63 (No. 2) ◽  
pp. 79-85 ◽  
Author(s):  
Tunji Oloyede Christopher ◽  
Bukola Akande Fatai ◽  
Olaniyi Oriola Kazeem ◽  
Oluwatoyin Oniya Oluwole
Keyword(s):  
Thermal Conductivity ◽  
Heat Capacity ◽  
Thermal Properties ◽  
Thermal Diffusivity ◽  
Moisture Content ◽  
Specific Heat ◽  
Specific Heat Capacity ◽  
Oil Recovery ◽  
Thermal Analyser ◽  
Selection Of

The thermal properties of soursop seeds and kernels were determined as a function of moisture content, ranged from 8.0 to 32.5% (d.b.). Three primary thermal properties: specific heat capacity, thermal conductivity and thermal diffusivity were determined using Dual-Needle SH-1 sensors in KD2-PRO thermal analyser. The obtained results shown that specific heat capacity of seeds and kernels increased linearly from 768 to 2,131 J/kg/K and from 1,137 to 1,438 J/kg/K, respectively. Seed thermal conductivity increased linearly from 0.075 to 0.550 W/m/K while it increased polynomially from 0.153 to 0.245 W/m/K for kernel. Thermal diffusivity of both seeds and kernels increased linearly from 0.119 to 0.262 m<sup>2</sup>/s and 0.120 to 0.256 m<sup>2</sup>/s, respectively. Analysis of variance results showed that the moisture content has a significant effect on thermal properties (p ≤ 0.05). These values indicated the ability of the material to retain heat which enhances oil recovery and can be used in the design of machine and selection of suitable methods for their handling and processing.

scholarly journals Moisture dependent thermal properties of selected vegetables in Akwa Ibom State, Nigeria

2019 ◽  
Vol 65 (No. 2) ◽  
pp. 56-62
Author(s):  
Olugbenga Abiola Fakayode ◽  
Olayemi Olubunmi Ojoawo
Keyword(s):  
Experimental Data ◽  
Thermal Conductivity ◽  
Thermal Properties ◽  
Thermal Diffusivity ◽  
Linear Regression ◽  
Moisture Content ◽  
Specific Heat ◽  
Regression Equations ◽  
Content Variation

The thermal properties of some selected vegetables in Akwa Ibom State, Nigeria were investigated. The specific heat, thermal conductivity and thermal diffusivity for the five selected vegetables (Afang, Nkong, Atama, Editan and Nton) were determined and the moisture content variation was investigated. The specific heat values ranged from 2,348–4,580 J·kg<sup>–1</sup>·K<sup>–1</sup>, while the thermal conductivity values ranged from 0.00368–0.489 and the thermal diffusivity values ranged from 1.03 × 10<sup>–7</sup>–1.99 × 10<sup>–7</sup> m<sup>2</sup>·s<sup>–1</sup>. Nton had the highest specific heat and thermal conductivity, while Editan had the highest diffusivity. An increase in the moisture content increased the specific heat, thermal conductivity and diffusivity of the vegetables and the relationships were found to be linear. Regression equations for the thermal properties were established as a function of the product’s moisture content with the experimental data from this study. The thermal properties of the vegetables varied linearly with the moisture content and there were significant differences in the thermal properties of the selected vegetables.

scholarly journals Influence of Moisture and Temperature on the Thermal Properties of Jack Bean Seeds (Canavalia ensiformis)

2021 ◽  
Author(s):  
Jelili Hussein ◽  
Moruf Olanrewaju Oke ◽  
Kazeem Olaniyi Oriola ◽  
Abimbola Ajetunmobi
Keyword(s):  
Thermal Conductivity ◽  
Heat Capacity ◽  
Thermal Properties ◽  
Thermal Diffusivity ◽  
Moisture Content ◽  
Specific Heat ◽  
Specific Heat Capacity ◽  
Jack Bean ◽  
Canavalia Ensiformis ◽  
Thermal Analyzer

The thermal properties (specific heat capacity, thermal conductivity, and thermal diffusivity) of jack bean seed (Canavalia ensiformis) were determined for usage in designing the equipment necessary for thermal processes. These thermal properties were determined at 5, 10, 15, 20, and 25 % moisture contents (wb) and temperatures at 30, 40, and 50oC using the KD2 Pro thermal analyzer. Results showed that the specific heat capacity ranged from 1.55 to 2.47 kJ/kgK, 1.26 to 1.84 kJ/kgK and 1.32 to 1.99 kJ/kgK; thermal conductivity 0.21 to 0.47 W/mK, 0.34 to 0.52 W/mK, and 0.26 to 0.60 W/mK and thermal diffusivity 0.25 to 0.41 x 10-7 m²/s, 0.32 to 0.57 x 10-7 m²/s, and 0.32 to 0.60 x 10-7 m²/s at 30, 40, and 50°C respectively for the moisture ranges studied. The temperature and moisture content effect were not significant (p>0.05) with specific heat and thermal diffusivity but significant (p<0.05) with thermal conductivity in third-order polynomial. A non-linear relationship was established between the three thermal properties and moisture content within the studied temperature range. The resulting regression models for the thermal properties gave a high coefficient of determinations (R2 ≥ 0.7995) which implies that they can be used to describe the relationships between temperature, moisture, and thermal properties of jack bean seeds.

scholarly journals Thermal Properties of New Developed Nigerian Illa and Ekpoma Rice Flour Varieties as Effected with Moisture Content

2021 ◽  
Vol 2 (2) ◽  
pp. 460-471
Author(s):  
Ide PATRICK EJIKE ◽  
Ikoko OMENAOGOR
Keyword(s):  
Thermal Conductivity ◽  
Heat Capacity ◽  
Thermal Properties ◽  
Thermal Diffusivity ◽  
Moisture Content ◽  
Specific Heat ◽  
Bulk Density ◽  
Specific Heat Capacity ◽  
Rice Flour ◽  
Thermal Parameters

Thermal parameters of food flour moisture content and temperature give an insight in the development and prediction of models that meet the needs of process design models, it also determine the thermal load of a particular product during handling. The bulk density (ρ), thermal conductivity (k), specific-heat capacity (Cp) and diffusivity (α) of Illa and Ekpoma rice flour were studied at varied (MC) moisture content (%) level. The results showed significance in thermal properties values at the different MC levels. The MC increased from 10.56 to 18.50%, increased the specific heat capacity (Cp) from 5.72 to 48.61kJ kg-1 °C-1 and 6.84 to 29.41 kJ kg-1 °C-1 for Illa and Ekpoma rice variety respectively and thermal conductivity(k) from 0.03 to 1.56 W/m0C and 0.03 to 0.38 W m-1 °C-1 for Illa and Ekpoma rice flour samples. Thermal diffusivity(α) and bulk density (ρ) of the processed Illa and Ekpoma rice flour samples decreased across the MC range of 10.56 to 18.50% (d.b). Thermal diffusivity(α) decreased from 4.38 to 1.25 x 10-4 m2 s-1 and 3.42 to 1.30 x 10-4 m2 s-1 for Illa and Ekpoma rice flour respectively while the values of bulk density (ρ) decreased from 697.72 to 676.34 kg m-3 and 687.49 to 664.26 kg m-3 for Illa and Ekpoma rice flour respectively.The developed model equations can be applied in estimation of thermal parameters of rice flour. Finally, Ekpoma and Illa rice flour sample displayed good thermal characteristics and it can be used as an alternative to imported wheat flour.

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 Compressive strength and thermal properties of sand–bentonite mixture

2021 ◽  
Vol 13 (1) ◽  
pp. 988-998
Author(s):  
Mindaugas Zakarka ◽  
Šarūnas Skuodis ◽  
Giedrius Šiupšinskas ◽  
Juozas Bielskus
Keyword(s):  
Thermal Conductivity ◽  
Compressive Strength ◽  
Thermal Properties ◽  
Moisture Content ◽  
High Voltage ◽  
Power Lines ◽  
Thermal Resistivity ◽  
Mechanical And Thermal Properties ◽  
Protective Material ◽  
Dry Mixing

Abstract Sand–bentonite mixtures are used in road embankments as a protective material for protecting underground high-voltage cables and utility pipelines supplying water and gas etc. The sand–bentonite mixtures provide benefits while laying high-voltage cables. The purpose of this study is to determine the proportions as well as mechanical and thermal properties of a dry-mixed sand–bentonite mixture and to investigate the suitability of such mixtures for installation around high-voltage underground power lines in road embankments. When selecting a sand–bentonite mixture, the following requirements must be ensured: the compressive strength must be greater than 0.5 MPa after 24 h; the thermal resistivity must be greater than 1.2 K m/W (thermal conductivity 0,833 W/(K m)); and the moisture content of the sand–bentonite mixture must be less than 13%. The following materials were used when selecting the bentonite mixture: bentonite, 0–4.0 mm fraction sand, cement (CEM I 42.5R), and water. In this study, six groups of samples were formed, in which the parts of concrete, sand, cement, and water were added in different proportions. The strength and thermal conductivity of the samples were analyzed. Studies about the use of bentonite around high-voltage cables have revealed the need for wet mixing of bentonite suspensions. The required thermal conductivity properties of the soil were not achieved by dry mixing. This method of mixing can be useful only in cases when the thermal conductivity of the mixed soil is not relevant, because the work can be continued after a day.

scholarly journals Effect of Iron Ore Tailings Particle Sizes on the Thermal Properties of Epoxy and Polypropylene Matrix Composites

2020 ◽  
Vol 5 (2) ◽  
Author(s):  
Johnson O Oyebode ◽  
Vivian N Mbagwu ◽  
Modupe A Onitiri ◽  
Olayinka O Adewumi
Keyword(s):  
Thermal Conductivity ◽  
Heat Capacity ◽  
Thermal Properties ◽  
Thermal Diffusivity ◽  
Specific Heat ◽  
Matrix Composite ◽  
Specific Heat Capacity ◽  
Iron Ore ◽  
Thermal Resistivity ◽  
Iron Ore Tailings

Thermal properties of materials such as plastic matrix composite is one of the important parameters for determining their behaviour and relevant applications. This present work focuses on determining the thermal behaviour of epoxy and polypropylene (PP) matrix composite reinforced with iron ore tailings (IOT) particulates of sizes 150 µm, 212 µm and 300 µm at various loadings of 5%, 10%, 15%, 20%, 25%, and 30%. The thermal behaviour of the developed composites was investigated experimentally using a KD2 pro thermal analyser. The results obtained from the experiment showed that increasing filler loading in epoxy leads to increased specific heat capacity and thermal resistivity. The maximum values recorded for the thermal resistivity and specific heat capacity were 0. 592°C.m/W and 2.352 J/kgK respectively. Thermal conductivity and thermal diffusivity of values 0.168W/mK and 0.089 mm²/s respectively were the lowest obtained for the epoxy matrix composite. It was also observed that addition of IOT in PP had significant effect on the thermal properties of the PP composite. Thermal conductivity and thermal diffusivity were found to increase with increased particle loading compared to the pure PP sample; the highest value being 2.235 W/mK and 5.51 mm²/s for thermal conductivity and thermal diffusivity respectively while low values of 0.05 Cm/W and 0.371 J/kgK was recorded for thermal resistivity and specific heat capacity. The presence of iron ore tailings reduces the thermal conductivity and diffusivity in epoxy but increases the conductivity and diffusivity in polypropylene. Keywords— Composite, Epoxy, IOT, Polypropylene, Composite, Thermal Conductivity

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