Thermal conductivity, thermal diffusivity, and specific heat capacity of particle filled polypropylene

2004 ◽  
Vol 35 (4) ◽  
pp. 423-429 ◽  
Author(s):  
Bernd Weidenfeller ◽  
Michael Höfer ◽  
Frank R Schilling
Keyword(s):  
Thermal Conductivity ◽  
Heat Capacity ◽  
Thermal Diffusivity ◽  
Specific Heat ◽  
Specific Heat Capacity

scholarly journals Comparative study of thermal transport in Zea mays straw and Zea mays heartwood (cork) boards

2010 ◽  
Vol 14 (1) ◽  
pp. 31-38 ◽  
Author(s):  
Sunday Etuk ◽  
Louis Akpabio ◽  
Ita Akpan
Keyword(s):  
Thermal Conductivity ◽  
Heat Capacity ◽  
Zea Mays ◽  
Thermal Diffusivity ◽  
Comparative Study ◽  
Specific Heat ◽  
Specific Heat Capacity ◽  
Thermal Transport ◽  
Insulation Material ◽  
Thermal Absorptivity

Thermal conductivity values at the temperature of 301-303K have been measured for Zea mays straw board as well as Zea mays heartwood (cork) board. Comparative study of the thermal conductivity values of the boards reveal that Zea mays heartwood board has a lower thermal conductivity value to that of the straw board. The study also shows that the straw board is denser than the heartwood board. Specific heat capacity value is less in value for the heartwood board than the straw board. These parameters also affect the thermal diffusivity as well as thermal absorptivity values for the two types of boards. The result favours the two boards as thermal insulators for thermal envelop but with heartwood board as a preferred insulation material than the straw board.

Influence of Mesocarp Fibre Inclusion on Thermal Properties of Foamed Concrete

2021 ◽  
Vol 87 (1) ◽  
pp. 1-11
Author(s):  
Siti Shahirah Suhaili ◽  
Md Azree Othuman Mydin ◽  
Hanizam Awang
Keyword(s):  
Thermal Conductivity ◽  
Heat Capacity ◽  
Thermal Properties ◽  
Thermal Diffusivity ◽  
Specific Heat ◽  
Specific Heat Capacity ◽  
Volume Fraction ◽  
Thermal Constant ◽  
Volume Fractions ◽  
Foamed Concrete

The addition of mesocarp fibre as a bio-composite material in foamed concrete can be well used in building components to provide energy efficiency in the buildings if the fibre could also offer excellent thermal properties to the foamed concrete. It has practical significance as making it a suitable material for building that can reduce heat gain through the envelope into the building thus improved the internal thermal comfort. Hence, the aim of the present study is to investigate the influence of different volume fractions of mesocarp fibre on thermal properties of foamed concrete. The mesocarp fibre was prepared with 10, 20, 30, 40, 50 and 60% by volume fraction and then incorporated into the 600, 1200 and 1800 kg/m3 density of foamed concrete with constant cement-sand ratio of 1:1.5 and water-cement ratio of 0.45. Hot disk thermal constant analyser was used to attain the thermal conductivity, thermal diffusivity and specific heat capacity of foamed concrete of various volume fractions and densities. From the experimental results, it had shown that addition of mesocarp fibre of 10-40% by volume fraction resulting in low thermal conductivity and specific heat capacity and high the thermal diffusivity of foamed concrete with 600 and 1800 kg/m3 density compared to the control mix while the optimum amount of mesocarp fibre only limit up to 30% by volume fraction for 1200 kg/m3 density compared to control mix. The results demonstrated a very high correlation between thermal conductivity, thermal diffusivity and specific heat capacity which R2 value more than 90%.

Thermal Properties of Electro Insulating Paper

2019 ◽  
Vol 955 ◽  
pp. 25-30
Author(s):  
Lucie Marackova ◽  
Veronika Melcova ◽  
Josef Samek ◽  
Oldrich Zmeskal
Keyword(s):  
Thermal Conductivity ◽  
Heat Capacity ◽  
Thermal Diffusivity ◽  
Specific Heat ◽  
Specific Heat Capacity ◽  
Temperature Response ◽  
Differential Method ◽  
Thermal Parameters ◽  
Insulating Paper ◽  
Steady State Temperature

This paper is focused on the determination of thermal parameters (thermal conductivity, thermal diffusivity, and specific heat capacity) of electrical insulating paper from various producers. The transient step-wise method was used to determine all thermal parameters simultaneously. Evaluation was carried out using the differential method. Thermal conductivity was determined from the steady-state temperature response on thickness (corresponding to the number of paper layers), while thermal diffusivity and specific heat capacity was obtained from the dependence of derivative maximum and the corresponding temperature on thickness. Four electro insulating papers differing by composition and thickness: materials NKN (Nomex-Kapton-Nomex), DMD (Dacron-Mylar-Dacron), TFT (TufQUIN TFT 50) and TVAR (ThermaVolt AR) were studied. As a result, the highest value of thermal conductivity (0.17 W/m/K) was determined for the DMD. Remaining three materials possessed thermal conductivity about 0.12 W/m/K. However, differences in specific heat capacity and thermal diffusivity were found to be significantly higher. The lowest specific heat capacity was found for the DMD sample (1200 J/kg/K), while the highest specific heat capacity was found for TVAR sample (4000 J/kg/K).

scholarly journals On the Use of Thermal Properties for Characterizing Dimension Stones

2013 ◽  
Vol 548 ◽  
pp. 231-238 ◽  
Author(s):  
Paulo Amaral ◽  
António Correia ◽  
Luís Lopes ◽  
Paula Rebola ◽  
António Pinho ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Heat Capacity ◽  
Thermal Properties ◽  
Thermal Diffusivity ◽  
Specific Heat ◽  
Specific Heat Capacity ◽  
Heat Production ◽  
Civil Engineering ◽  
Chemical Properties ◽  
Usual Practice

The use of dimension stones in architecture and civil engineering implies the knowledge of several mechanical, physical, and chemical properties. Even though it has been usual practice to measure physical and mechanical properties of dimension stones the same is not true for thermal properties such as thermal conductivity, thermal diffusivity, specific heat capacity, and heat production. These properties are particularly important when processes related with heating and cooling of buildings must be considered. Thermal conductivity, thermal diffusivity, and specific heat capacity are related with the way thermal energy is transmitted and accumulated in stones; heat production has to do with the amount of radioactive elements in the rocks and so with the environmental impact of radioactivity and public health problems. It is important to start to measure on a routine basis those four thermal properties in rocks and, in particular, in dimension rocks so that their application can be improved and optimized. With this is mind three sets of different rock types (granites, limestones, and marbles) were collected to measure the thermal conductivity, the thermal diffusivity, and the specific heat capacity with the objective of characterizing them in terms of those properties. Since the same set of rocks has also been studied for other physical properties, a correlation amongst all the measured properties is attempted. For each rock type several samples were used to measure the thermal conductivity, the thermal diffusivity, and the specific heat capacity, and average values were obtained and are presented. As an example, for granites the thermal conductivity varies between 2.87 and 3.75 W/mK; for limestones varies between 2.82 and 3.17 W/mK; and for marbles varies between 2.86 and 3.02 W/mK. It is hoped that measuring thermal properties on dimension stones will help to better adequate them to their use in civil engineering as well as to adequate their use in terms of a CE product.

scholarly journals Effect of cooking time on the physical, chemical and thermal properties of acha seeds

2017 ◽  
Vol 6 (2) ◽  
Author(s):  
Akeem O. Raji ◽  
Hajarat O. Nassam ◽  
Tawakalitu E. Aruna ◽  
Monsurat O. Raji ◽  
Maimuna Sani
Keyword(s):  
Thermal Conductivity ◽  
Heat Capacity ◽  
Thermal Properties ◽  
Thermal Diffusivity ◽  
Aspect Ratio ◽  
Specific Heat ◽  
Specific Heat Capacity ◽  
Cooking Time ◽  
Crude Fibre ◽  
Cereal Grain

Acha is a less utilized cereal grain in Africa. Scaling up of the processing technology of acha seeds is desirable if accurate information on effect of processing on its properties is available. This study investigated the effect of cooking duration on the chemical and physical properties of acha seeds. Cooking times (2.5, 5, 7.5 and 10 minutes) at 100oC were used. The volume, length, breadth, thickness, porosity, density, sphericity, aspect ratio, specific heat capacity, thermal conductivity, thermal diffusivity, moisture, protein, fat, ash, crude fibre and carbohydrate were determined using standard methods. Data were analysed using ANOVA at p = 0.05. The results obtained revealed that varietal difference had a significant effect on volume, length, breadth, thickness, true density, bulk density, porosity, sphericity and aspect ratio. The moisture content, ash, protein, crude fibre, fat, carbohydrate, specific heat capacity, thermal conductivity and thermal diffusivity varied from 8.80 - 56.17 %, 0.32 - 1.87%, 1.92 - 11.50%, 0.29 - 1.58%, 0.32 - 2.81%, 40.94 - 76.26%, 1.66 -2.97 kJkg-1K-1, 0.26 -0.43 Wm-1K-1 and 0.85 x 10-7 - 1.17 x 10-7 ms-2 respectively, as significantly influenced by cooking time. Cooking for 7.5 minutes was appropriate using the moisture uptakes and thermal properties as criteria. 

scholarly journals Characterization of AlN-based Ceramic Composites for Use as Millimeter Wave Susceptor Materials at High Temperature: High Temperature Thermal Properties of AlN:Mo with 0.25% to 4.0% Mo by Volume

MRS Advances ◽  
2019 ◽  
Vol 4 (27) ◽  
pp. 1531-1542 ◽  
Author(s):  
Brad W. Hoff ◽  
Frederick W. Dynys ◽  
Steven C. Hayden ◽  
Rachael O. Grudt ◽  
Martin S. Hilario ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Heat Capacity ◽  
High Temperature ◽  
Thermal Diffusivity ◽  
Specific Heat ◽  
Specific Heat Capacity ◽  
Elevated Temperatures ◽  
Ceramic Composites ◽  
Dsc Measurements ◽  
Mo Content

ABSTRACTIn order to begin to evaluate and model the suitability of high temperature ceramic composites, such as AlN:Mo, as susceptor materials for power beaming applications, the electromagnetic, thermal, and mechanical properties of the material must be known at elevated temperatures. Work reported here focuses on the development of thermal property datasets for AlN:Mo composites ranging from 0.25% to 4.0% Mo by volume. To calculate thermal conductivity of the AlN:Mo composite series, specific heat capacity, thermal diffusivity, and density data were acquired. The calculated specific heat capacity, Cp, of the set of AlN:Mo composites was, on average, found to be approximately 803 J/kgK at 100 °C and to increase to approximately 1133 J/kgK at 1000 °C, with all values to be within +/- 32 J/kgK of the average at a given temperature. These calculated specific heat capacity values matched values derived from DSC measurements to within the expected error of the measurements. Measured thermal diffusivity, α, of the set of AlN:Mo composites was, on average, found to be approximately 3.93 x 10-1 cm2/s at 100 °C and to increase to approximately 9.80 x 10-2 cm2/s at 1000 °C, with all values within +/- 1.84 x 10-2 cm2/s of the average at a given temperature. Thermal conductivity, k, for the set of AlN:Mo composites was found to be approximately 108 W/mK at 100 °C and to decrease to approximately 38 W/mK at 1000 °C, with all values within +/- 5.3 W/mK of the average at a given temperature. Data trends show that increasing Mo content correlates to lower values of of Cp, α, and k at a given temperature.

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.

Sign in / Sign up

Export Citation Format

Share Document