scholarly journals Thermal Characterization of a New Bio-Based Insulation Material Containing Puffed Rice

Energies ◽  
2021 ◽  
Vol 14 (18) ◽  
pp. 5700
Author(s):  
Maatouk Khoukhi ◽  
Abeer Dar Saleh ◽  
Ahmed Hassan ◽  
Shaimaa Abdelbaqi
Keyword(s):  
Thermal Conductivity ◽  
Thermal Characterization ◽  
Insulation Material ◽  
Optimal Range ◽  
Insulation Materials ◽  
Material Optimization ◽  
Sample Amount ◽  
Puffed Rice ◽  
Influential Parameters

Although many advanced insulation materials have been recently developed, very few are eco-friendly and their production requires a substantial amount of energy and complex manufacturing processes. To address this issue, a bio-based thermal insulation material was developed using short- and long-grained puffed rice. A set of experiments was subsequently carried out to identify the best rice type and the optimal range for the most influential parameters (sample amount, temperature, and moisture level). Our findings revealed that short-grained rice exhibited greater puffing ability and was thus adopted in further material optimization experiments. These assessments indicated that the most optimal thermal conductivity of the insulation material and the highest puffing ratio was attained at 12–15% moisture, 260–270 °C temperature, and 15–18 g sample weight. The thermal properties, including thermal conductivity and fire reaction, and thermal performance of samples obtained using these parameters were similar to those of common insulation materials.

scholarly journals Thermal characterization of different graphite polystyrene

2018 ◽  
Vol 9 (2) ◽  
pp. 163-168 ◽  
Author(s):  
Á. Lakatos ◽  
I. Deák ◽  
U. Berardi
Keyword(s):  
Thermal Conductivity ◽  
High Performance ◽  
Thermal Characterization ◽  
Expanded Polystyrene ◽  
High Moisture ◽  
Insulating Materials ◽  
Insulation Materials ◽  
Vacuum Insulation ◽  
Study Laboratory

The development of high performance insulating materials incorporating nanotechnologies has enabled considerable decrease in the effective thermal conductivity. Besides the use of conventional insulating materials, such as mineral fibers, the adoption of new nano-technological materials such as aerogel, vacuum insulation panels, graphite expanded polystyrene, is growing. In order to reduce the thermal conductivity of polystyrene insulation materials, during the manufacturing, nano/micro-sized graphite particles are added to the melt of the polystyrene grains. The mixing of graphite flakes into the polystyrene mould further reduces the lambda value, since graphite parts significantly reflect the radiant part of the thermal energy. In this study, laboratory tests carried out on graphite insulation materials are presented. Firstly, thermal conductivity results are described, and then sorption kinetic curves at high moisture content levels are shown. The moisture up-taking behaviour of the materials was investigated with a climatic chamber where the relative humidity was 90% at 293 K temperature. Finally, calorific values of the samples are presented after combusting in a bomb calorimeter.

Evaluation of Thermal Characterization Techniques and Tools for Thermal Conductivity Measurement of Sub 100 Angstrom Thick Silicon Layers

2007 ◽  
Author(s):  
Keivan Etessam-Yazdani ◽  
Mehdi Asheghi
Keyword(s):  
Thermal Conductivity ◽  
Conductivity Measurement ◽  
Thermal Characterization ◽  
Phonon Transport ◽  
Thermal Conductivity Measurement ◽  
Great Success ◽  
Silicon Structures ◽  
Thin Silicon ◽  
20 Nm

Experimental measurement of thermal conductivity is considered the most reliable tool for the study of phonon transport in ultra-thin silicon structures. While there has been a great success in thermal conductivity measurement of ultra-thin silicon layers down to 20 nm over the past decade, it is not clear if the existing techniques and tools can be extended to the measurements of sun 100 Angstrom layers. In this paper, an analytical study of the feasibility of electrical Joule heating and thermometry in patterned metal bridges is presented. It is concluded that thermal conductivity of silicon layers as thin as 5 nm can be obtained (uncertainty 20%) by performing steady-state measurements using an on-substrate nanoheater structure. The thermal characterization of silicon layers as thin as 1 nm may be possible using frequency domain measurements.

scholarly journals Thermal Performance of Oil Palm Fibre and Paper Pulp as the Insulation Materials

2014 ◽  
Vol 5 (2) ◽  
pp. 22-28
Author(s):  
S.H. Ibrahim ◽  
Sia W.K. ◽  
A. Baharun ◽  
M.N.M. Nawi ◽  
R. Affandi
Keyword(s):  
Thermal Conductivity ◽  
Thermal Performance ◽  
Oil Palm ◽  
Total Density ◽  
Insulation Material ◽  
Paper Pulp ◽  
Particle Board ◽  
Environment Impact ◽  
Palm Fiber ◽  
Insulation Materials

 Energy consumption for residential use in Malaysia is keep increasing yearly in order to maintain the internal thermal comfort of the building. Roof insulation material plays a vital role in improving the thermal comforts of the building while reduce the cooling load of the building. Oil palm industry in Malaysia had grown aggressively over the past few decades. Tons of oil palm waste had produced during the process such as empty fruit bunch fiber. Another waste material that available and easy to obtain is paper. Paper is a valuable material that can be recycled. Waste paper comes from different sources such as newspaper, office and printing papers. This study will take advantage of the available resources which could contribute to reduce the environment impact. The aim of this study is to investigate the thermal performance of roof insulation materials using mixture of oil palm fiber and paper pulp with different ratio and thickness. This study found that the thermal performance of the paper pulp is slightly better compare to the oil palm fiber. Thermal conductivity of the particle board reduces around 4.1% by adding the 10% of paper pulp into the total density of the particle board. By adding 75% of paper pulp, the thermal conductivity of the particle board could be reduced to 24.6% compare to the oil palm fiber board under the similar condition. Therefore, from this study, it could be concluded that paper pulp has high potential to be used as a building insulation material.

scholarly journals Technical Performance Overview of Bio-Based Insulation Materials Compared to Expanded Polystyrene

Buildings ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 81
Author(s):  
Cassandra Lafond ◽  
Pierre Blanchet
Keyword(s):  
Thermal Conductivity ◽  
Energy Efficiency ◽  
Natural Fibers ◽  
Expanded Polystyrene ◽  
Embodied Energy ◽  
Lower Amount ◽  
Vapor Permeability ◽  
Insulation Material ◽  
Insulation Materials ◽  
Technical Performance

The energy efficiency of buildings is well documented. However, to improve standards of energy efficiency, the embodied energy of materials included in the envelope is also increasing. Natural fibers like wood and hemp are used to make low environmental impact insulation products. Technical characterizations of five bio-based materials are described and compared to a common, traditional, synthetic-based insulation material, i.e., expanded polystyrene. The study tests the thermal conductivity and the vapor transmission performance, as well as the combustibility of the material. Achieving densities below 60 kg/m3, wood and hemp batt insulation products show thermal conductivity in the same range as expanded polystyrene (0.036 kW/mK). The vapor permeability depends on the geometry of the internal structure of the material. With long fibers are intertwined with interstices, vapor can diffuse and flow through the natural insulation up to three times more than with cellular synthetic (polymer) -based insulation. Having a short ignition times, natural insulation materials are highly combustible. On the other hand, they release a significantly lower amount of smoke and heat during combustion, making them safer than the expanded polystyrene. The behavior of a bio-based building envelopes needs to be assessed to understand the hygrothermal characteristics of these nontraditional materials which are currently being used in building systems.

Preparation and Properties of Ultrafine Glass Wool by Centrifugal Blowing

2011 ◽  
Vol 148-149 ◽  
pp. 116-120
Author(s):  
Jin Lian Qiu ◽  
Zhao Feng Chen ◽  
Jie Ming Zhou ◽  
Jian Wang ◽  
Bin Bin Li ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Glass Fiber ◽  
Average Diameter ◽  
Glass Wool ◽  
Insulation Material ◽  
Insulation Materials ◽  
Materials Engineering ◽  
Acoustic Insulation ◽  
Fiber Reinforcements ◽  
Predominant Process

Due to extremely low thermal conductivity, high modulus, high toughness, light weight and non-combustible property, ultrafine glass wool can be widely used as glass fiber reinforcements in composites, thermal insulation materials, acoustic insulation materials, engineering materials, construction, infrastructure and environmental protection projects and so on. In particular, as a insulation material, glass wool exhibits unique advantages. The predominant process of glass wool is centrifugal blowing process. This paper describes a study of the relationship between the diameter of ultrafine glass fiber and thermal conductivity. The thermal conductivity of ultrafine glass wool decreases with the decrease of average diameter.

scholarly journals Thermal characterization of fibrous aerogel blanket

2019 ◽  
Vol 282 ◽  
pp. 01001 ◽  
Author(s):  
Ákos Lakatos ◽  
Anton Trnik
Keyword(s):  
Thermal Annealing ◽  
Thermal Insulation ◽  
Thermal Characterization ◽  
Insulation Material ◽  
Scanning Calorimetry ◽  
Solid Materials ◽  
Plastic Foams ◽  
Isothermal Heat Treatments ◽  
New Buildings

Nowadays, the application of thermal insulation materials both by the existing and by new buildings is one of the most important actions in order to reduce the energy loss of buildings. Besides the use of the conventional insulations (plastic foams and wool materials) aerogel is one of the most promising thermal insulation material. Aerogels, one of the lightest solid materials available today, are manufactured through the combination of a polymer with a solvent forming a gel. For buildings the fibre reinforced ones are the mainly used types. It is produced by adding the liquid-solid solution to the fibrous batting. In this paper changes in the thermal performance of the aerogel blanket will be followed after thermal annealing. The samples will be put under isothermal heat treatments at 70 °C for 6 weeks, as well as they will be put under thermal treatment at higher temperatures (from 70 °C till 210 °C) for 1 day. The changes in the thermal conductivity will be followed by Holometrix Lambda heat flow meter, as well as, Differential Scanning Calorimetry results will be presented. From the measured values, thermal properties will be calculated. In this paper we will try to clarify the role played by thermal annealing in thermal diffusivity.

Effect of Operating Temperatures on Thermal Conductivity of Polystyrene Insulation Material: Impact on Envelope-Induced Cooling Load

2014 ◽  
Vol 564 ◽  
pp. 315-320 ◽  
Author(s):  
Maatouk Khoukhi ◽  
Mahmoud Tahat
Keyword(s):  
Thermal Conductivity ◽  
Thermal Insulation ◽  
Energy Performance ◽  
Building Envelope ◽  
Insulation Material ◽  
Cooling Load ◽  
Thermal Insulation Material ◽  
Insulation Materials ◽  
Energy Performance Of Buildings ◽  
The Impact

The impact of the thermal conductivity (k-value) change of polystyrene insulation material in building envelope due to changes in temperature on the thermal and energy performance of a typical residential building under hot climate is investigated. Indeed, the thermal and energy performance of buildings depends on the thermal characteristics of the building envelope, and particularly on the thermal resistance of the insulation material used. The thermal insulation material which is determined by its thermal conductivity, which describes the ability of heat to flow cross the material in presence of a gradient of temperature, is the main key to assess the performance of the thermal insulation material. When performing the energy analysis or calculating the cooling load for buildings, we use published values of thermal conductivity of insulation materials, which are normally evaluated at 24°C according to the ASTM standards. In reality, thermal insulation in building is exposed to significant and continuous temperature variations, due essentially to the change of outdoor air temperature and solar radiation. Many types of insulation materials are produced and used in Oman, but not enough information is available to evaluate their performance under the prevailing climatic condition. The main objective of this study is to investigate the relationship between the temperature and thermal conductivity of various densities of polystyrene, which is widely used as building insulation material in Oman. Moreover, the impact of thermal conductivity variation with temperature on the envelope-induced cooling load for a simple building model is discussed. This work will serve as a platform to investigate the effect of the operating temperature on thermal conductivity of other building material insulations, and leads to more accurate assessment of the thermal and energy performance of buildings in Oman.

scholarly journals Review on Techniques for Thermal Characterization of Graphene and Related 2D Materials

Nanomaterials ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 2787
Author(s):  
Jing Liu ◽  
Pei Li ◽  
Hongsheng Zheng
Keyword(s):  
Thermal Conductivity ◽  
Energy Transport ◽  
Large Deviation ◽  
2D Materials ◽  
Single Layer ◽  
Thermal Characterization ◽  
Great Depth ◽  
Characterization Methods ◽  
Critical Issues

The discovery of graphene and its analog, such as MoS2, has boosted research. The thermal transport in 2D materials gains much of the interest, especially when graphene has high thermal conductivity. However, the thermal properties of 2D materials obtained from experiments have large discrepancies. For example, the thermal conductivity of single layer suspended graphene obtained by experiments spans over a large range: 1100–5000 W/m·K. Apart from the different graphene quality in experiments, the thermal characterization methods play an important role in the observed large deviation of experimental data. Here we provide a critical review of the widely used thermal characterization techniques: the optothermal Raman technique and the micro-bridge method. The critical issues in the two methods are carefully revised and discussed in great depth. Furthermore, improvements in Raman-based techniques to investigate the energy transport in 2D materials are discussed.

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