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# A Study on Insulation Characteristics of Glass Wool and Mineral Wool Coated with a Polysiloxane Agent

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The insulation in buildings is very important. Insulation used in the building is largely divided into organic and inorganic insulation by its insulation material. Organic insulation materials which are made of Styrofoam or polyurethane are extremely vulnerable to fire. On the other hand, inorganic insulation such as mineral wool and glass wool is very weak with moisture, while it is nonflammable, so that its usage is very limited. Therefore, this study developed moisture resistance applicable to mineral wool and glass wool and measured the thermal conductivity of the samples which are exposed to moisture by exposing the product coated with moisture resistance and without moisture resistance to moisture and evaluated how the moisture affects thermal conductivity by applying this to inorganic insulation.
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Research Article
A Study on Insulation Characteristics of Glass Wool and
Mineral Wool Coated with a Polysiloxane Agent
Chan-Ki Jeon,1Jae-Seong Lee,1Hoon Chung,2Ju-Ho Kim,1and Jong-Pil Park1
1Department of Urban Engineering, Incheon National University, 119 Academy-ro, Yeonsu-gu, Incheon 406-772, Republic of Korea
2SunHan M&T, 663-13 Gojan-dong, Namdong-gu, Incheon 405-818, Republic of Korea
Correspondence should be addressed to Jong-Pil Park; jp@inu.ac.kr
Received  October ; Accepted  December ; Published  January 
which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
e insulation in buildings is very important. Insulation used in the building is largely divided into organic and inorganic insulation
by its insulation material. Organic insulation materials which are made of Styrofoam or polyurethane are extremely vulnerable
to re. On the other hand, inorganic insulation such as mineral wool and glass wool is very weak with moisture, while it is
nonammable, so that its usage is very limited. erefore, this study developed moisture resistance applicable to mineral wool and
glass wool and measured the thermal conductivity of the samples which are exposed to moisture by exposing the product coated
with moisture resistance and without moisture resistance to moisture and evaluated how the moisture aects thermal conductivity
by applying this to inorganic insulation.
1. Introduction
e issues of saving energy and reducing carbon dioxide
emissions are concerns and important research projects
inallcountries.Forthis,theproductdevelopmentwhich
maximized energy eciency has been in progress and, in
recent years, the research on the new insulation material
development such as VIP (Vacuum Insulation Panels) using
fumed silica and GFP (Gas-Filled Panels) using Argon (Ar),
krypton (Kr), and xenon (Xe) gases which have a lower
thermal conductivity than air has been actively progressed
[, ].
Insulation boards are being used in various areas such as
modern architecture and other industries, and these insula-
tion boards are manufactured and used in various forms [].
However, most of insulation is synthetic insulation in a foam
type, where porosities are created inside of the product, ber
type insulation which uses glass wool or mineral wool in a
nonwoven fabric type made from fabric material and board
products which use inorganic binders such as cement with
perlite and ceramic ball [].
While insulation can be classied by raw material, type,
and purpose of use, it is generally classied by material.
According to material, insulation can be divided into organic
insulation and inorganic insulation. In the case of organic
insulation, it has an excellent thermal performance, absorp-
tion, and workability, so that it occupies more than % of
the domestic market; however, in case of re, Styrofoam and
urethane have less than  seconds in ignition time and the
time taken for ame spread is  seconds, so that re rapidly
spreads and toxic gases generated during combustion such as
formaldehyde, ethylene cyanide (CH=CHCN), hydrochloric
acid gas, and cyanide gas are very critical to the human body
[].
In the case of inorganic insulation, it has an excellent re
resistance characteristic but its absorbability is very high, so
that it has a drawback in that its insulation performance is
poor []. While the thermal conductivity of air is . W/mk
[], water has . W/mk which is  times the thermal
conductivity of air []. And also ice has . kcal/mhCof
thermal conductivity which is about  times or more the
thermal conductivity of air, so that the water content of
material can be the most inuencing element determining
thermal conductivity [].
While thermal conductivity change in insulation material
by water absorption has been widely reported, the research
Hindawi
Advances in Materials Science and Engineering
Volume 2017, Article ID 3938965, 6 pages
https://doi.org/10.1155/2017/3938965
Advances in Materials Science and Engineering
TEOS.MTES H2O/ethaonol, IPA
Stirring for 10min
Stirring for 3~5hrs
Transparent SiO2sol
F : Synthesis of silica sol
for retaining insulation eect has not been reported, so that
this study developed a moisture resistance and conrmed
the waterproof ability of inorganic insulation by processing
inorganic insulation materials, glass wool and mineral wool,
with the moisture resistance, exposing them to moisture and
measuring the amount of moisture increase and thermal
conductivity [–].
Inparticular,thisstudymeasuredtheprocesswherethe
heat on the surface is transferred and the temperature chance
of the surface occurs according to the water absorption of
mineral wool and glass wool by utilizing a thermal imaging
camera and observed the eect and process that moisture
does on insulation material [].
2. Experimental Device and Test Methods
2.1. Experimental Device and Specimen. While there are
comparative thermal conductivity measuring methods such
asthermalconductivityheatowmeterandhotwiremethod
[], this study tested thermal conductivity measurement
according to the KS L  Test and the test was made by
using a thermal conductivity meter (HFM-) by thermal
conductivity heat ow method. e glass wool and mineral
wool used in this study used Korea KCC products. And the
specimen size is × ×mmperKSL,KSF
 test standard. Regarding the measurement of specimen,
the thickness of the specimen was measured precisely and
the thermal conductivity was measured in a place where
surrounding temperature around the experiment space was
kept constant. e thermal conductivity coecient of the
measured specimen was calculated by Fouriers law of heat
conduction or the following equation []:
𝑑𝑄
𝑑𝑇 =−𝐴𝑘𝛿𝑇
𝛿𝑥 ,()
where 𝑑𝑄/𝑑𝑇 is heat ow rate/heat ux density [(J/m2s)] =
[Watt/m2],indicates that heat ow direction is the direction
Si
O
O
O
H3C
H3C
CH3
NH2
(a)
F3CCF2CF2
CF2CF2
CF2Si(OCH2CH3)3
CH2
CH2
(b)
F : Silane compound constitutional formula: (a) -aminopro-
pyltriethoxysilane; (b) tridecauoro-,,,-tetrahydrooctyl--trie-
thoxysilane.
cooling, 𝐴is cross section (m2),𝑘is thermal conductivity
[J/(msK)],and𝛿𝑇/𝛿𝑥 is temperature gradient (heat ow
driving force) (K/m).
When looking at (), the amount of heat conduction
by unit time is proportional to the cross-sectional area
contacting with the temperature dierence and is inversely
proportional to the distance.
2.2. Preparation of Moisture Resistance. e moisture-
resistant liquid in this study used nanosilicate which is
manufactured in-house and uoroalkylsiloxane compound
and its preparation process is as follows [].
2.3. Preparation of Silica Sol. Ethanol . kg (. mol) and
concentrated hydrochloric acid  g (. mol) are put into
water . and mixed and then a mixed solution of
tetraethoxysilane . kg ( mol) and methyltriethoxysilane
 g (. mol) is added. en, silica sol solution is obtained
by stirring for  hours at room temperature. is process was
conrmed by SEM and nanoparticle size analyzer and the
reactionformulaisasfollows(Figure)[].
2.4. Preparation of Organosiloxane Containing Fluorinated
Alkyl Group. Tridecauoro-,,,-tetrahydrooctyl--triethox-
ysilane . kg ( mol) is added to . kg of puried water
slowly. While stirring this solution, acetic acid  g ( mol) is
added and stirred for  hours and then tridecauoro-,,,-
tetrahydrooctyl--triethoxysilane (uorine organosiloxane)
e reaction between tridecauoro-,,,-tetrahydro-
octyl--triethoxysilane and -aminopropyltriethoxysilane
was conrmed with FT-IR.
2.5. Preparation of Fluoroalkylsiloxane Moisture Resistance
(SH-AF). % silica sol of  mL solution and % organo-
siloxane of  mL are added and mixed into  mL of
puriedwaterandthen,mLmoisture-resistantsolution
is prepared.
2.6. Applying Moisture Resistance. When it comes to the
samples for measuring the thermal conductivity, the glass
wool and mineral wool specimens with  × × mm
Advances in Materials Science and Engineering
T : Moisture absorption amount of mineral wool before and aer SH-AF treatment.
Classication Weight of the sample before SH-AF coating Weight of the sample aer SH-AF coating
Before humidication (g) . .
Aer humidication (g) . .
Water content (g) . .
Percentage of moisture content (%) . .
A: Glass wool
B: Humidier
C: Hygrometer
C
B
A
F : Schematic drawing of the whole experimental set-up.
sizeareimpregnatedintheuoroalkylsiloxanesolutionfor
seconds and then are prepared by drying for  hours at C.
Whenitcomestothesamplesformeasuringtheabsorp-
tion rate, they are created into  × × mm size to
facilitate the humidication experiment and then they are
impregnated in the uoroalkylsiloxane solution for  seconds
andthenarepreparedbydryingforhoursat
C.
e comparison was done by SEM to compare between
the samples with the uoroalkylsiloxane treatment and the
samples with no uoroalkylsiloxane treatment.
2.7. Absorption Measurement. Whilethereareapouring
method and spray method to supply water for the measure-
ment of the amount of absorption between mineral wool
and glass wool samples with a coating and without a coating
andduetothethermalconductivitychangebyabsorption
and the temperature change transmitted to the surface, this
study supplied water by placing a humidier in an acrylic
box of  mm in length, width, and height as shown in
Figure , leaving the sample for  hours with the hygrometer,
indicating more than % in humidity.
2.8. ermal Imaging Camera Measurement. In order to
observe the diusion of heat through thermal conductivity
and a thermal imaging camera depending on the water supply
method and water content of glass wool and mineral wool
insulation materials, a hot plate was used as heat source and
the temperature was xed at C. Regarding the thermal
imaging camera, the products of PI and FL companies were
used for the observation. At the time, the camera was xed
in order to measure the temperature of the surface and the
middle of the sample.
3. Results
3.1. Preparation of Fluoroalkylsiloxane
3.1.1. Preparation of Silica Sol. e observation result with
TEM (Transmission Electron Microscopy) by diluting syn-
thesized SiO sol with ethanol in a ratio of  :  showed
that spherical SiO nanoparticles with approximate size of
 nm were created (Figure ) similar to the particle size
analysis.emeasurementresultofsynthesizedsilicasolby
theparticlesizeanalyzer(ZetasizerNanoZS,Malvern)
conrmed that the average particle size was .nm and very
uniform sizes of SiO nanoparticles were synthesized within
±. nm in the particle size distribution.
3.2. SEM Photos. e test result shows that SH-AF has been
well coated to mineral wool and glass wool as shown in
Figure  which compares the sample with moisture resistance
and the sample with no moisture resistance with SEM photos.
3.3. ermal Conductivity. e measurement result of ther-
mal conductivity for each test piece shows that thermal
conductivity of typical mineral wool is .W/mk and
thermalconductivityofmineralwoolwithSH-AFprocessed
is.W/mk,sothatitbecomeslower.Also,incase
of glass wool, thermal conductivity of typical glass wool is
. W/mk and thermal conductivity of glass wool with
SH-AF processed is .W/mk, which means it becomes a
littlebitlowerinthesamewayasmineralwool.So,basedon
these results, it was conrmed that SH-AF treatment makes
thermal conductivity lower so that insulation performance
increases a little bit [] (see Figure ).
3.4. Water Absorption Amount of Specimen and ermal
Conductivity of Mineral Wool with Moisture. Wei g h t c h a n g e
shown from the moisture absorption measurement aer
supplying moisture for  hours through a humidier is shown
in Tables  and . Typical mineral wool absorbed .% of
moisture and mineral wool with coated SH-AF did .%
of moisture. Typical glass wool absorbed .% of moisture
and one with coated SH-AF did only .% of moisture. is
result conrms that SH-AF moisture resistance developed
Advances in Materials Science and Engineering
(a) (b)
F : TEM of nanosilica: (a)  nm silica TEM picture; (b)  nm silica TEM picture.
(a) (b)
(c) (d)
F : SEM of mineral wool and Glass wool: (a) mineral wool; (b) mineral wool coated with SH-AF; (c) glass wool; (d) glass wool coated
with SH-AF.
T : Moisture absorption amount of glass wool before and aer SH-AF treatment.
Classication Weight of the sample before SH-AF coating Weight of the sample aer SH-AF coating
Before humidication (g) . .
Aer Humidication (g) . .
Water content (g) . .
Percentage of moisture content (%) . .
Advances in Materials Science and Engineering
0.035
0.034
0.033
0.032
0.031
0.030
ermal conductivity (W/mk)
Classication
Mineral wool Mineral wool coated with SH-AF
Glass wool Glass wool coated with SH-AF
F : ermal conductivity of mineral wool and glass wool.
Time (mins)
0510 15 20 25 30 35
10
15
20
25
30
35
40
Glass ber
Moisturized glass ber
Glass ber with SH-AF treatment
Moisturized glass ber with SH-AF treatment
Temperature (C)
F : Surface temperature change in glass ber before and aer
moisturizing.
in this study can be applied to existing inorganic insulation
materials.
It was found that the glass wool with moisture has
. W/mk in thermal conductivity so that thermal conduc-
tivity increases  times compared to .W/mk shown in
typical glass wool.
3.5. Temperature Change in Inorganic Material. Figure 
showstheglasswoolsamplewithmoistureresistance(SH-
AF) treatment and one without that and the temperature
change of the glass wool sample with moisture resistance
(SH-AF) treatment and one without that. Aer moisture is
supplied for  hours through a humidier for each sample
[],thetemperaturechangeonthesideandtopsurface
of insulation material was checked with a thermal imaging
camera. e result shows that while the glass wool with
moisture resistance (SH-AF) treatment has no big change in
surface temperature, the temperature arises suddenly aer
being kept low in the beginning with the glass wool specimen
with no moisture-resistant coating. It can be understood that
the moisture in inorganic insulation material evaporates and
then the performance of insulation material is reduced. It
canbefoundthatthemoisture-resistant(SH-AF)treatment
prevents thermal conductivity of the sample to rapidly drop
by moisture [].
4. Conclusion
In this paper, the temperature change of insulation material
was measured aer applying uoroalkylsiloxane moisture
resistance developed in-house to typical inorganic insulation
materials and the condition similar to the summer monsoon
period was applied to inorganic insulation material by the
humidication method as a way of moisturizing in the test.
e experimental results are as follows:
() Inorganic insulation materials such as glass ber or
mineral wool are extremely vulnerable to moisture so
that they absorbed water % of their weight and
thermal conductivity increased more than  times so
that it is dicult to expect a proper performance as
insulation in a high humidity area.
() Fluoroalkylsiloxane (SH-AF) moisture resistance
developedinthisstudysuppressedmoisture
absorption when applied to inorganic insulation
so that it can prevent thermal conductivity from
being increased by moisture which is a drawback of
inorganic insulation material.
() In previous researches, pouring method or spray
method was used for testing as a method of supplying
water to inorganic insulation material, but when eval-
uating the impact that moisture makes on insulation
performance, it is eective to evaluate the eect of
moisture with a more realistic moisturizing method
so that setting up a standard test method is necessary.
()Withtheconventionaltestingdeviceformeasur-
ing the thermal conductivity, thermal conductiv-
ity of insulation material with moisture cannot be
measured so that hot wire method was used to
measure thermal conductivity of insulation mate-
rial with moisture. erefore, a standard method
formeasuringchangeinthermalconductivityby
moisture absorption in insulation material should be
presented.
Competing Interests
e authors declare that they have no competing interests.
Acknowledgments
is study was performed by the research funding from Korea
Institute of Energy Technology Evaluation and Planning
(Project no. ).
Advances in Materials Science and Engineering
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propertie s and thermal resistance f unction of permeable as phalt
concrete,Gongneng Cailiao/Journal of Functional Materials,
vol.,no.,pp.,.
... Organic fibres offer various advantages, such as low density, low cost, biodegradability, and low energy consumption during the processing of the material [75,76]. In the case of organic insulation, it has excellent thermal performance, absorption, and workability [77]. ...
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Malaysia, like most other developing countries, is facing an increase in the generation of waste and accompanying problems with the disposal of this waste. A large number of biomass wastes were generated due to increased activity in the agricultural and agro-industrial sectors, which led to producing environmental hazards and waste management issues. On the other situation, the energy consumption to cool the indoor building environment is high due to the building being exposed directly to solar radiation throughout the daytime, which increases the temperature outside and inside the building. Most of the low-medium cost housing schemes were constructed using metal roof covering without providing a roof insulation layer which causes a rising in indoor temperature and creates uncomfortable surroundings. Moreover, existing materials for roof insulation in the market use inorganic synthetic materials that could harm human health. The study aims to investigate the potential use of agricultural wastes for the production of roof board insulation material that can provide economic value added to agricultural waste, reduce the environmental issue and provide eco-friendly, sustainable building material. In this study, these agricultural wastes are combined in different proportions of 50% individual fibres, such as sugarcane bagasse with coconut husk, empty fruit bunch with mesocarp fibre, coconut husk with empty fruit bunch, and sugarcane bagasse with mesocarp fibre. The sample was fabricated using the hot-press machine and went through various physical and mechanical testing, which involved thickness of swelling, modulus of rupture, and thermal conductivity. The finding showed that the mixed fibre of empty fruit bunch and mesocarp fibre achieved all the criteria such as density (427 <500kg/m3); thickness of swelling (19< 20%); modulus of rupture (514<800psi), thermal conductivity (0.0856<0.25 W/m.K) met with the standard requirement in every laboratory test conducted. The outcome of this study suggests that empty fruit bunch and mesocarp fibre are the potential materials for the production of roof board thermal insulation. However, modification of physical and mechanical properties of waste fibre is required to achieve superior performance and is ready to be provided in the market. This study is aligned with the government initiative for the growth of green building materials for sustainable development in the construction industry.
... Faster linear drop in thermal conductivity (from 0.14 to 0.082 W/m•K, or by 39.8%) is observed when HGM content is increased from 0 to 2.5 wt%. Less steep linear decrease is observed from 2.5 wt% to 10 wt% HGM content leading to the total decrease in thermal conductivity down to 0.059 W/m•K (or by 57% relative to the pristine PDMS), which is already between the thermal conductivity of asbestos (0.08 W/m•K [22]) and mineral wool (0.04 W/m•K [23]). This is a significantly more pronounced effect than the one reported for PDMS-HGM composite by Vlassov Fig. 1. ...
Article
The possibility of reducing the thermal conductivity of the composite material based on polydimethylsiloxane by adding hollow glass microspheres as fillers was tested. Based on the data obtained, it can be concluded that a composite material containing microspheres at a concentration of 2.5% has a lower thermal conductivity coefficient by 40%, but also loses adhesion work and transparency in the optical range.
... These qualities have made glass wool, rock wool, and ceramic wool extremely desirable for pipe insulation, building insulation, industrial furnace insulation, and refrigerated transportation and medical hygiene applications. Inorganic insulation materials have unique advantages in fireresistance, non-aging, low cost, and environmental benignity compared to organic insulation materials-as discussed in: Stazi et al. (2014), Chan-Ki et al. (2017). ...
Chapter
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In this chapter, the methods of synthesis of polyetherols with incorporated azacyclic rings are described. The polyetherols obtained by hydroxyalkylation of isocyanuric, uric, and barbituric acids, adenine, and melamine with oxiranes, formaldehyde, and alkylene carbonates are characterized. These hydroxyalkylated azacycles are shown as substrates to obtain rigid polyurethane foams of enhanced thermal resistance. Also, the current state of molecular modification of foam compositions in order to decrease the flammability of foams is described. The decrease of flammability can be achieved by azacycle-derived polyetherol modification with boron and silicon, as well as by addition of flame retardants. Additionally, it has been shown that natural polymers; starch and cellulose can be successfully hydroxyalkylated with glycidol and alkylene carbonates. The polyetherols obtained from cellulose and starch can be applied to obtain highly thermally resistant, biodegradable polyurethane foams, which are the milestones in green chemistry of polymers.
... Its made from a combination of recycled sand and glass (Swami, 2014). The thermal conductivity of glass wool is 0.0343 W/mK (Jeon et al., 2017). The heat loss (q rt ) permitted per 1 m length of a well-insulated pipe is 25 W (Singh and Heldman, 2001). ...
Article
Purpose Refractance window drying (RWD) has been identified as the method that can give high-quality products at a relatively low production cost. However, knowledge about its use and adoption remains lacking both in academic curricula and industry in the developing world. Design/methodology/approach A lab-scale batch RWD of a closed-loop control system was designed, fabricated and evaluated for drying rates, evaporation rate, the energy of evaporation, energy efficiency and throughput. Testing was done using mango and tomato pulps. Findings Drying rates at 95°C of 1.32 gg ⁻¹ min ⁻¹ and 0.854 gg ⁻¹ min ⁻¹ at 2 and 3 mm, respectively, for tomato, 0.6 gg ⁻¹ min ⁻¹ and 0.33 gg ⁻¹ min ⁻¹ at 2 and 3 mm for mango pulp were obtained. The dryer had an evaporation rate of 4.63 × 10 –4 kg/s and 4.25 × 10 –4 kg/s, the energy of evaporation of 1.05 kW and 0.96 kW and thermal energy efficiency of 25.64% and 21.73% while drying tomato and mango pulps, respectively. Dryer throughput of 0.6 kg/h of dried mango Pulp and 0.47 kg/h of dried tomato pulp was obtained. Originality/value The designed RWD can be adequately used in laboratory experiments on different products to produce powders. This will enable the transfer of knowledge about RWD technology in developing countries.
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This research aimed to find the process of value adding for glass wool waste from the glass wool composite board used in the vehicle industry. The waste was reprocessed to be an insulator and to determine the suitable conditions for hot-press forming to create new materials having high thermal resistant properties. Firstly, the properties of the original board; the thermal resistances (R) and the noise absorption coefficients (NRC), were measured and were found averages of 0.9055 m2K/W and 0.3955, respectively. The reprocessing conditions were varied by 2 levels; high and low, of 5 control factors; density, thickness, pressure, temperature, and surface roughness. Three repeating processes for each condition were performed. The Design of Experiment (DoE) was the full factorials; 25 experiments, by using the Analysis of Variance (ANOVA) to find main and interaction factors relating to the properties. From the ANOVA results with the α level of significance at 0.05, it was found that the main factors responding to the high values of the thermal resistance were the thickness and density. This resulted in the suitable conditions for the hot-press process of both the new smooth and rough pads with a density of 96 kg/m3 and a thickness of 25 mm. The R values of the new insulators were in between 0.88 – 0.98 m2K/W and, additionally, the high NRC values were also provided in between 0.46 – 0.49. These findings could be applied for wall designing, wall decorations and heat shields for indoor rooms and different types of buildings.
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Recently, foam glass thermal insulating decorative integrated board has been proposed as advanced external wall insulation. In the present study, the temperature and strain monitoring program is designed to investigate the synergistic of the integrated board and the base wall after installation on the building exterior wall. Moreover, variations of the temperature and strain fields of the system in different aging stages are studied. The obtained results show that the foam glass integrated board has an excellent performance in heat and cold preservation. It is found that the temperature difference between the concrete base layer and the finishing layer reaches 40°C. The temperature fluctuation range of the base layer is only 4°C and 9°C in hot-rain cycles and the heat-cold cycles, respectively. Moreover, it is found that the strain fluctuations of the finishing layer are relatively severe, and the deformation range of −1000με～+2500με and the plastic deformation of +1500με may occur in the hot-rain cycle, and the range of −2000με～+1500με and the plastic deformation of −600με may occur in the heat-cold cycle. Finally, the concept of thermal insulation degradation degree (DT) is proposed. The obtained results reveal that DT rises from 0 to 0.23 in the hot-rain cycle and from 0 to 0.36 in the heat-cold cycle. Through the analysis of the strain changes, the synergistic mechanism of the integrated board and the base wall in the aging process is studied. The present article is expected to provide a theoretical guideline to design foam glass integrated boards.
Chapter
Inorganic insulations such as glass wool, rock wool, and ceramic wool have the characteristics of lightweight, low thermal conductivity, high sound-absorbing performance, chemical durability, and non-combustibility. Therefore, these inorganic insulation materials have been widely used as high-quality heat-insulating and sound-absorbing materials in transport systems, the nuclear power industry, and refrigeration as well as buildings. The centrifugal-blow process and flame-blow process are mainly used for the manufacturing of inorganic wools. The chemical composition, classification, fabrication technology, equipment, characteristics, and applications of glass wool, rock wool, and ceramic wool will be discussed in this chapter.
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Steam cooking using parabolic trough collectors is a well-established sustainable technology. The augmentation of a thermal energy storage (TES) system with such a sustainable system will make the technology completely reliable on the renewable energy source. However, there are limited research findings to improve the thermal performance of the TES heat exchangers by adopting non-structural and non-elemental modifications. In this article, experimental studies have been performed on a TES shell and tube heat exchanger that could be envisaged for steam cooking applications. Erythritol was used as the phase change material. The heat exchanger was operated in two modes: progressive and impulsive. From the observations, the performance of the impulsive mode was better than the progressive mode. The impulsive mode of functionality witnessed a 32% decrease in the charging duration, 2.5% increase in the energy stored and 50% increase in the charging rate in comparison to the progressive mode.
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This paper analyzes the impact of a change in the thermal insulating material on both the energy and environmental performance of a building, evaluated through two different green building assessment methods: Leadership in Energy and Environmental Design (LEED) and Istituto per l'innovazione e Trasparenza degli Appalti e la Compatibilità Ambientale (ITACA). LEED is one of the most qualified rating systems at an international level; it assesses building sustainability thanks to a point-based system where credits are divided into six different categories. One of these is fully related to building materials. The ITACA procedure derives from the international evaluation system Sustainable Building Tool (SBTool), modified according to the Italian context. In the region of Umbria, ITACA certification is composed of 20 technical sheets, which are classified into five macro-areas. The analysis was developed on a residential building located in the central Italy. It was built taking into account the principles of sustainability as far as both structural and technical solutions are concerned. In order to evaluate the influence of thermal insulating material, different configurations of the envelope were considered, replacing the original material (glass wool) with a synthetic one (expanded polystyrene, EPS) and two natural materials (wood fiber and kenaf). The study aims to highlight how the materials characteristics can affect building energy and environmental performance and to point out the different approaches of the analyzed protocols.
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In this study, conventional solid reinforced concrete (RC) beams were modified to slotted beams for consideration as thermal insulation structural components. The slotted beam was consisted of an outer and an inner beam respectively, with a slot located near the middle of the beam along its width direction for filling thermal insulation material. Flexural and thermal behavior of the slotted beams were investigated. Three RC reference solid beams and six slotted beams were fabricated and tested under four point bending tests. The test results indicated that the failure mode of both slotted beams and the solid beams was flexural failure. However, the damage process of the slotted beams was different from that of the solid beams at the final loading stage. The moment curvature analysis indicated that the tensile reinforcement ratio of the outer and inner beams had an important effect on the flexural behavior, especially the ductility of the slotted beams. Thermal study indicated that the heat transfer coefficient of the slotted beam was greatly reduced and the thermal inertia factor increased a lot, compared with the solid beam. In addition, FE simulation results showed that a new frame structure using slotted beams exhibited obvious and attractive thermal insulation property.
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In order to research thermophysical properties of permeable asphalt concrete, the indexes such as thermal conductivity, specific heat capacity and thermal diffusivity was computational researched between permeable asphalt and density graded asphalt concrete based on thermodynamic theory, the relationships between thermophysical properties of permeable asphalt concrete with air void & moisture content were analyzed; indoor irradiation experiment was designed for determination the temperature change of PAC & AC specimens. Theoretical calculation results indicate that permeable asphalt concrete is reduced by 20% with thermal conductivity, 10% with thermal diffusivity, which is compared with density graded asphalt concrete; indoor temperature measurement results indicate that compared with density graded asphalt the temperature is decreased by 2-2.5°C in the surface and 3-3.5°C in the bottom of permeable asphalt concrete specimen, shows that permeable asphalt has function of thermal resistance, has strong resistant ability for the temperature load variation. Theoretical calculation results were verified.
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This paper presents a critical review of current industrial techniques and instruments to measure the thermal conductivity of thermal insulation materials, especially those insulations that can operate at temperatures above $$250\,^{\circ }\hbox {C}$$ and up to $$800~^{\circ }\hbox {C}$$ . These materials generally are of a porous nature. The measuring instruments dealt with here are selected based on their maximum working temperature that should be higher than at least $$250\,^{\circ }\hbox {C}$$ . These instruments are special types of the guarded hot-plate apparatus, the guarded heat-flow meter, the transient hot-wire and hot-plane instruments as well as the laser/xenon flash devices. All technical characteristics listed are quoted from the generally accessible information of the relevant manufacturers. The paper includes rankings of the instruments according to their standard retail price, the maximum sample size, and maximum working temperature, as well as the minimum in their measurement range.