This study examined the thermal conductivity and behavior of three wood species from the Combretaceae family - Terminalia superb, Terminalia ivorensis, and Quisqualis indica. Samples were tested using a modified Lee's disk method at different temperature and time intervals. The results showed that thermal agitation increased with temperature until stability was reached after around 105 minutes. Thermal equilibrium was achieved faster during decreasing temperatures. Terminalia superb exhibited the highest thermal conductivity and agitation, followed by Terminalia ivorensis, with Quisqualis indica showing the lowest. The thermal conductivity values for all samples fell within the typical range of 0.1-0.8 Wm-1K-1 for wood materials
Comparative Cooling Efficiency of Brick Walls for Poultry House in Hot Climat...Premier Publishers
The attainment of thermo-neutral condition in a poultry house is determined, to some extent, by the choice of wall materials. The extent to which bricks produce desired cooling in relation to other materials as walls for poultry houses is uncertain. This study was aimed at determining the relative cooling efficiency of brick walls over sand-crete block walls on one hand, and a combination of thatch insulation and iron-roofing sheets on the other. The quasi-experimental research design employed thermo-anemometer to determine temperatures inside five poultry houses: three made up of brick-walls; one of sand-crete block-walls; and one of insulated iron roofing sheet-walls. Analysis of variance (ANOVA) was employed to establish any significant difference in temperature in the houses (at 0.05 level of significance). The result showed that brick walls have higher cooling efficiency than the other materials, but not at a significant level. Also, thermo-neutral condition was not attained in any of the five poultry houses. It was recommended that architectural strategies that may further reduce temperature to thermo-neutral condition in poultry houses be investigated.
Laboratory Performance Of Evaporative Cooler Using Jute Fiber Ropes As Coolin...IJERA Editor
Evaporative coolers use a variety of cooling media like wood wool, cellulose, aspen. This paper analyses the performance of jute fiber ropes as alternative cooling media. They are capable of retaining high moisture and have a large wetted surface area. Hot and dry air is allowed to flow over the wet jute rope bank tightly held between two plates which are integral part of two tanks. The inlet conditions of air varied from 30.5 0C dry bulb temperature and 52 % relative humidity to 34.5 0C dry bulb temperature and 32 % relative humidity. Outlet temperature of air is measured and saturation efficiency and cooling capacity are calculated. The outlet dry bulb temperature is obtained between 25.8 0C and 26.2 0C.The saturation efficiencies range from 69 % to 59 % and the cooling capacity is obtained between 6173 kJ/h and 11979 kJ/h. Thus jute fiber ropes prove to be a good alternative cooling media in evaporative cooler.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
Comparative Cooling Efficiency of Brick Walls for Poultry House in Hot Climat...Premier Publishers
The attainment of thermo-neutral condition in a poultry house is determined, to some extent, by the choice of wall materials. The extent to which bricks produce desired cooling in relation to other materials as walls for poultry houses is uncertain. This study was aimed at determining the relative cooling efficiency of brick walls over sand-crete block walls on one hand, and a combination of thatch insulation and iron-roofing sheets on the other. The quasi-experimental research design employed thermo-anemometer to determine temperatures inside five poultry houses: three made up of brick-walls; one of sand-crete block-walls; and one of insulated iron roofing sheet-walls. Analysis of variance (ANOVA) was employed to establish any significant difference in temperature in the houses (at 0.05 level of significance). The result showed that brick walls have higher cooling efficiency than the other materials, but not at a significant level. Also, thermo-neutral condition was not attained in any of the five poultry houses. It was recommended that architectural strategies that may further reduce temperature to thermo-neutral condition in poultry houses be investigated.
Laboratory Performance Of Evaporative Cooler Using Jute Fiber Ropes As Coolin...IJERA Editor
Evaporative coolers use a variety of cooling media like wood wool, cellulose, aspen. This paper analyses the performance of jute fiber ropes as alternative cooling media. They are capable of retaining high moisture and have a large wetted surface area. Hot and dry air is allowed to flow over the wet jute rope bank tightly held between two plates which are integral part of two tanks. The inlet conditions of air varied from 30.5 0C dry bulb temperature and 52 % relative humidity to 34.5 0C dry bulb temperature and 32 % relative humidity. Outlet temperature of air is measured and saturation efficiency and cooling capacity are calculated. The outlet dry bulb temperature is obtained between 25.8 0C and 26.2 0C.The saturation efficiencies range from 69 % to 59 % and the cooling capacity is obtained between 6173 kJ/h and 11979 kJ/h. Thus jute fiber ropes prove to be a good alternative cooling media in evaporative cooler.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
Se evalúa la factibilidad de páneles de celdek, luffa, paja y sacos de arpillera, como materiales alternativos de empaque para enfriamiento evaporativo en invernaderos.
Theoretical Model Computations for Different Components of a Hot Box Type Sol...IJCMESJOURNAL
Many countries having tremendous solar potentials are also the victim of the power crises since the available solar energy is not utilized efficiently. It has been recognized that the widespread use of solar thermal appliances (STA) for domestic work is being held back by excessive cost, low efficiency, high weight, and inconvenience of user and by lack of confidence in the long term durability of the material. In the present work, the limitations of materials used in various components of commercial available STA have been underlined and it has been shown that use of polymeric materials as specific component in solar thermal appliances can solve most of the existing limitations and may improve the efficiency of the existing appliances. In this paper theoretical model computations have been done for different components of a hot-box type solar cooker viz., glaze, insulation and casing material for the spectral transmittance, the solar flux absorbed and the optical efficiency, thermal efficiency, heat loses, weight, thermal profile and adjusted cooking power for several suitable materials, both conventional as well as new polymeric materials. Significant improvement in all the mentioned characteristic properties /figures of merit of the solar cooker can be achieved if right combination of polymeric materials is used in making glaze, insulation and casing. The present study offers that component improvements of a system results into cost reduction, extended lifetime and makes system easy to handle. This shall surely help in popularization of the solar appliances and enhancement of eco-friendly environment.
Dielectric and Thermal Characterization of Insulating Organic Varnish Used in...Editor IJCATR
In recent days, a lot of attention was being drawn towards the polymer nanocomposites for use in electrical applications due
to encouraging results obtained for their dielectric properties. Polymer nanocomposites were commonly defined as a combination of
polymer matrix and additives that have at least one dimension in the nanometer range scale. Carbon nanotubes were of a special
interest as the possible organic component in such a composite coating. The carbon atoms were arranged in a hexagonal network and
then rolled up to form a seamless cylinder which measures several nanometers across, but can be thousands of nanometers long. There
were many different types, but the two main categories are single-walled nanotubes (SWNTs) and multi-walled nanotubes (MWNTs),
which are made from multiple layers of graphite. Carbon nanotubes were an example of a nanostructure varying in size from 1-100
nanometers (the scale of atoms and molecules). Nano composites were one of the fastest growing fields in nanotechnology. Extensive
literature survey has been done on the nanocomposites, synthesis and preparation of nano filler. The following objectives were set
based on the literature survey and understanding the technology.
Complete study of Organic varnish and CNT
Chemical properties
Electrical properties
Thermal properties
Mechanical properties
Synthesis and characterization of carbon nanotubes
Preparation of polymer nanocomposites
Study of characteristics of the nanocomposite insulation
Dimensioning an insulation system requires exact knowledge of the type, magnitude and duration of the electric stress while
simultaneously considering the ambient conditions. But, on the other hand, properties of the insulating materials in question must also
be known, so that in addition to the proper material, the optimum, e.g. the most economical design of the insulation system must be
chosen.
Building materials used for the walls of simple houses in lower-middle-class areas in Indonesia are currently dominated by brick. This study proposes that soil-paper blocks coated with calcium silicate board may be a suitable alternative, with high embodied energy and density. The research aims to obtain an optimal wall thickness to provide protection against cooling and embodied energy in low income houses, as well as against the temperature conditions in these buildings in highland and lowland areas. Determination of wall thickness is performed by simulation of a 9 m2 building model with thick variables. Cooling calculations involved the use of Archipak software. Temperature measurements were carried out using a data logger on a sample of soil-paper blocks. The results indicate that the optimal wall thickness for protection against cooling and embodied energy is 8 cm. Soil-paper block has a lower density than brick. The use of calcium silicate boards does not affect the internal temperature of a low income house, but they can be used as protection against rainwater and as a substitute for wall plastering.
Preparation of Nanofluid (Al2O3-water) for Energy StorageIOSR Journals
Nanofluids are suspensions of nanoparticles in base fluids, a new challenge for thermal sciences providedby nanotechnology. Nanofluids have unique features different from conventional solid-liquid mixtures inwhich mm or μm sized particles of metals and non-metals are dispersed.At this research adding of small weight percent of Aluminum oxide (Al2O3) for weight percent of (0.1, 0.2, 0.3 and 0.4wt.%) to pure water as energy storage in different industrial applications ,which gave us different behavior, adding 0.1, 0.2 and 0.4wt,% gave low temperature gradient than the pure water, while 0.3 wt.% gave greater temperature gradient than pure water which is desired.
Natural Durability of Borassus aethiopum (Mart.) Wood Grown in Iwo, Osun Stat...Premier Publishers
Investigation of variation in density and the natural resistance of B. aethiopum wood was carried out using samples along (top, middle and base) and across (inner and outer) the bole of the tree. Samples collected were oven dried, weighed and subjected to field termite exposure test for a period of 52 weeks, after which, they were withdrawn, cleaned, dried and re-weighed. The result of this study showed variation in density of B. aethiopum across and along the bole of the tree with an average density of 806.495 kg/m3 which falls within the high-density wood classification. The result of the field exposure test showed a moderate correlation with the density. The gravimetric weight loss assessment showed that the inner portion had higher weight loss than the outer portion of the wood, revealing a higher resistance to termite attack. In order to ensure a higher reliability of B. aethiopum wood in service, cant sawing method should be used to separate the less durable inner portion of the wood from the outer portion.
PASSIVE THERMAL CONTROL FOR BUILDINGS IN TEMPERATE REGIONS-COMPARISON OF CAVI...paperpublications3
Abstract: Providing thermal comfort without excess space and conditioning costs is one of the primary requirements of buildings. Therefore, thermal control is an important aspect in almost all buildings. Understanding heat transfer and the temperature distribution through building materials and assemblies is also important for assessing energy use. Thermal comfort, thermal movements, durability, and the potential for moisture problems. The control of heat flow in buildings requires insulation layers compromised with few thermal bridges, an effective air barrier system, good control of solar radiation, and management of interior heat generation. Walls play a huge role in the heat gain and loss in buildings, thus, making wall an important subject in passive thermal control in buildings. This article is aimed at analyzing cavity walls and solid brick walls and comparing them for home construction in temperate regions. Temperate regions need good insulating walls, thus reducing heat loss via walls to its minimal, which in turn reduces the cost of active heating measures in buildings.
Flexural Strength of Solid and Glue-Laminated Timber BeamsIJERA Editor
An investigation into the flexural strength of solid and laminated timber beams under working conditions was
conducted. Six locally available species, which consist of three hardwoods and three softwoods were
investigated, which were Berlina, Danta, Alstonia, Agba, Ohia, and Obeche. The dimension of the hardwoods
solid beams are 100mm×100mm×900mm and softwoods solid beams are 150mm×150mm×900mm. The result
showed that the density of Berlina is 0.00128g/mm3, Danta is 0.000903g/mm3, Alstonia is 0.00816g/mm3, Agba
is 0.000724g/mm2, Ohia is 0.000716g/mm3 and Obeche is 0.000568g/mm3 and the weight for Berlina was
11.58kg, Danta was 8.13kg, Alstonia was 7.75kg, Agba was 14.67kg, Ohia was 14.5kg and Obeche was 11.5kg.
Comparing it with the maximum load the species could carry, Berlina was 108kN, Danta was 85.0kN, Alstonia
was 66.0kN, Agba was 50.0kN, Ohia was 103kN and Obeche was 60.0kN. Futhermore, twenty-four (24)
laminated timber beams of the same dimensions were manufactured with six (6) different species, viz: Afara,
Okwen, Danta, Obeche, Alstonia, Bombax. These beams were glued together using top-bond gum and allowed
to dry for twenty-four hours after which they were weighed before testing. The twenty-four beams were tested
to failure and the deflection reading taken from the dial-guage. Finally, a curve of deflection against the load
was plotted. It can be seen that with a stress of 10.80N/mm2, 8.50N/mm2, 6.60N/mm2, 2.222N/mm2, 4.58N/mm2
and 2.67N/mm2 the design stress, deflection criteria cannot be ignored, after comparing result from the
experiment, limiting deflection and actual deflection. A theoretical and experimental correlation of strength
evaluation was established for glue solid and glue laminated beams which were formed from combining timber
with glue.
The Effects of Flooring Material on Thermal Comfort in a Comparative Study Marble and Parquet Flooring
https://uijrt.com/articles/v1i5/UIJRTV1I50004.pdf
An Experimental Investigations of Nusselt Number for Low Reynolds Number in a...IJMER
: In this paper, we present results of measured heat transfer coefficients for each sodium
carboxymethyl cellulose concentration at two different lengths of coil L=2.82m, L=2.362m and with
two different heat inputs 1.0kW and 1.5kW . Test solutions of sodium carboxymethyl cellulose
concentrations of 0.05%, 0.1%, 0.15% and 0.2% were used in our experimental runs. A four flat blade
paddle impeller was used to verify the mixed fluid, under steady heating of Newtonian and nonNewtonian
fluids in an flat bottom agitated vessel. A Kanthal Heating Element Equipment have been
design and fabricated to optimize the heating of the fluids in an agitated vessel. The rehogical properties
like flow behavior index, consistency index and viscosity data were carried experimentally using Rotating
Cylinder Method for all the test solutions. A correlations have been presented for Newtonian and non
Newtonian fluids in laminar flow conditions
On the low temperature resistivity measurement of CdSe thin filmijtsrd
Most group II-VI compounds are direct band gap semiconductors with high optical absorption and emission coefficients .Cadmium Selenide is a leading candidate with high potential towards many applications. The authors present their investigations dealing with preparation and some electrical characterization of the CdSe thin films. The films were deposited onto a well-cleaned glass substrates using thermal evaporation technique. The dependence of electrical resistivity of CdSe thin film in low temperature range has been studied. R.K.Shah | H.O.Parmar | H.S.Patel"On the low temperature resistivity measurement of CdSe thin film" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-1 | Issue-2 , February 2017, URL: http://www.ijtsrd.com/papers/ijtsrd65.pdf http://www.ijtsrd.com/other-scientific-research-area/physics/65/on--the-low-temperature-resistivity-measurement-of-cdse-thin-film/rkshah
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Collectors innovation to increase performance solar water heatereSAT Journals
Abstract There have been many studies to improve the performance of the solar water heater. The long term goal of research is to obtain scientific information, teaching materials and as the foundation of scientific development of energy conversion. The specific objective of this study is to find or develop new models and models that can improve the efficiency of the solar water heater. Research methods; research conducted using the experimental method, which is to test the amount of cover glass, flow rate and preheat a working fluid that can improve the efficiency of solar water heater. Research output: 1) The efficiency of the best solar water heater is the sum of three layers of glass cover compared to the cover glass number two layers and one layer, 2) The greater the water flow rate, the efficiency of the solar water heater increases, 3) initial heating on water entry, exit and cause the water temperature absorber plate temperature is relatively the same, so the efficiency of the solar water heater close to zero. Keywords: number of glass cover, flow rate, initial heating, solar water heater
The basic density and some of the anatomical
properties of five clones of Eucalyptus tereticornis developed
by ITC Bhadrachalam were reported. The five clones
represented by four trees each of four and half years old were
from Sarapaka, Andhra Pradesh. Within tree variation in
anatomical properties of four and half years old grown
Eucalyptus tereticornis clones have been investigated and
correlated with basic density. Anatomical parameters studied
were found to vary significantly from bottom to top with no
definite trend. Significant variation exists in all the five clones
of different parameters. Basic density was positively correlated
with fibre length at middle, top and pooled positions. Fibre
length was positively correlated with fibre diameter, fibre
lumen diameter at bottom position, and with vessel diameter at
middle position, and negatively correlated with vessel
frequency at top position. The results obtained in this study
have shown the suitability of raw material for paper and pulp
where the required basic density is met with. Mainly these
clone are primarily tried to meet the requirement of paper and
pulp industry
It is widely accepted that heat treatment of wood ameliorates its dimensional stability and color evolution. This study has analyzed the effects of heat treatment in color changes and hygroscopic properties of fir wood (Abies Borissi-regis Mattf.), exposed at 200º C for 2, 3 and 4h. Dimensional stability and absorption were measured after 1 day and 3 days immersion in water of 20 º C ± 3 temperature. Color evolution and color changes were analyzed in three different directions using the CIE L*a*b* color space. The results showed that heat treatment resulted in a darkened color and an improvement in the dimensional stability of wood. The visual changes in color were more distinct after 4h treatment. The total color differences (ΔΕ) of the surface of wood substrates appear to be directly correlated with the treatment time. Swelling percentage of the samples was found to be affected by the thermal treatment intensity. The higher percentage of swelling decrease was recorded at approximately 19.61% in 4h treatment duration in a tangential direction whereas, the lowest percentage of 0.54% was derived from 3h treatment duration in a radial direction.
Research of Physical Properties of Straw for Building Panelsinventionjournals
The development of new thermal insulation materials needs to evaluate properties and structure of raw materials, technological factors that make influence on the thermal conductivity of material. One of the most promising raw materials for production of insulation material is straw. The use of natural fibres as insulation is closely linked to the ecological building sector, where selection of materials is based on factors including recyclable, renewable raw materials and low resource production techniques. In current work results of research on structure, thermal conductivity, water vapour permeability and short term water immersion of triticale straw for production of thermal insulating straw panels are presented. Straw panels withdifferent densitywere prepared for thermal conductivity measurement. It was determined that lowest thermal conductivity of straw is reached when straw density ranges from 80kg/m3 to 120 kg/m3 . It was found that the macrostructure that changes with density increase has the great effect on thermal conductivity of materials. At the density range of 120-190 kg/m3 increase of thermal conductivity values are observed. Water vapour permeabilitywas analysed at the density ranges from 80 kg/m3 to 156 kg/m3 . Vapour permeability values grew with density increase from 2 to 2.5. Short term water absorption was evaluated by two parameters - as water absorption coefficient due to capillary action and short term water absorption by partial immersion. Water absorption coefficient shows sudden mass increase within the first 10 minutes and subsequent slow mass increase. Short term water absorption values show significant weight increase during 48 hours, which reaches 100 percent by mass
Se evalúa la factibilidad de páneles de celdek, luffa, paja y sacos de arpillera, como materiales alternativos de empaque para enfriamiento evaporativo en invernaderos.
Theoretical Model Computations for Different Components of a Hot Box Type Sol...IJCMESJOURNAL
Many countries having tremendous solar potentials are also the victim of the power crises since the available solar energy is not utilized efficiently. It has been recognized that the widespread use of solar thermal appliances (STA) for domestic work is being held back by excessive cost, low efficiency, high weight, and inconvenience of user and by lack of confidence in the long term durability of the material. In the present work, the limitations of materials used in various components of commercial available STA have been underlined and it has been shown that use of polymeric materials as specific component in solar thermal appliances can solve most of the existing limitations and may improve the efficiency of the existing appliances. In this paper theoretical model computations have been done for different components of a hot-box type solar cooker viz., glaze, insulation and casing material for the spectral transmittance, the solar flux absorbed and the optical efficiency, thermal efficiency, heat loses, weight, thermal profile and adjusted cooking power for several suitable materials, both conventional as well as new polymeric materials. Significant improvement in all the mentioned characteristic properties /figures of merit of the solar cooker can be achieved if right combination of polymeric materials is used in making glaze, insulation and casing. The present study offers that component improvements of a system results into cost reduction, extended lifetime and makes system easy to handle. This shall surely help in popularization of the solar appliances and enhancement of eco-friendly environment.
Dielectric and Thermal Characterization of Insulating Organic Varnish Used in...Editor IJCATR
In recent days, a lot of attention was being drawn towards the polymer nanocomposites for use in electrical applications due
to encouraging results obtained for their dielectric properties. Polymer nanocomposites were commonly defined as a combination of
polymer matrix and additives that have at least one dimension in the nanometer range scale. Carbon nanotubes were of a special
interest as the possible organic component in such a composite coating. The carbon atoms were arranged in a hexagonal network and
then rolled up to form a seamless cylinder which measures several nanometers across, but can be thousands of nanometers long. There
were many different types, but the two main categories are single-walled nanotubes (SWNTs) and multi-walled nanotubes (MWNTs),
which are made from multiple layers of graphite. Carbon nanotubes were an example of a nanostructure varying in size from 1-100
nanometers (the scale of atoms and molecules). Nano composites were one of the fastest growing fields in nanotechnology. Extensive
literature survey has been done on the nanocomposites, synthesis and preparation of nano filler. The following objectives were set
based on the literature survey and understanding the technology.
Complete study of Organic varnish and CNT
Chemical properties
Electrical properties
Thermal properties
Mechanical properties
Synthesis and characterization of carbon nanotubes
Preparation of polymer nanocomposites
Study of characteristics of the nanocomposite insulation
Dimensioning an insulation system requires exact knowledge of the type, magnitude and duration of the electric stress while
simultaneously considering the ambient conditions. But, on the other hand, properties of the insulating materials in question must also
be known, so that in addition to the proper material, the optimum, e.g. the most economical design of the insulation system must be
chosen.
Building materials used for the walls of simple houses in lower-middle-class areas in Indonesia are currently dominated by brick. This study proposes that soil-paper blocks coated with calcium silicate board may be a suitable alternative, with high embodied energy and density. The research aims to obtain an optimal wall thickness to provide protection against cooling and embodied energy in low income houses, as well as against the temperature conditions in these buildings in highland and lowland areas. Determination of wall thickness is performed by simulation of a 9 m2 building model with thick variables. Cooling calculations involved the use of Archipak software. Temperature measurements were carried out using a data logger on a sample of soil-paper blocks. The results indicate that the optimal wall thickness for protection against cooling and embodied energy is 8 cm. Soil-paper block has a lower density than brick. The use of calcium silicate boards does not affect the internal temperature of a low income house, but they can be used as protection against rainwater and as a substitute for wall plastering.
Preparation of Nanofluid (Al2O3-water) for Energy StorageIOSR Journals
Nanofluids are suspensions of nanoparticles in base fluids, a new challenge for thermal sciences providedby nanotechnology. Nanofluids have unique features different from conventional solid-liquid mixtures inwhich mm or μm sized particles of metals and non-metals are dispersed.At this research adding of small weight percent of Aluminum oxide (Al2O3) for weight percent of (0.1, 0.2, 0.3 and 0.4wt.%) to pure water as energy storage in different industrial applications ,which gave us different behavior, adding 0.1, 0.2 and 0.4wt,% gave low temperature gradient than the pure water, while 0.3 wt.% gave greater temperature gradient than pure water which is desired.
Natural Durability of Borassus aethiopum (Mart.) Wood Grown in Iwo, Osun Stat...Premier Publishers
Investigation of variation in density and the natural resistance of B. aethiopum wood was carried out using samples along (top, middle and base) and across (inner and outer) the bole of the tree. Samples collected were oven dried, weighed and subjected to field termite exposure test for a period of 52 weeks, after which, they were withdrawn, cleaned, dried and re-weighed. The result of this study showed variation in density of B. aethiopum across and along the bole of the tree with an average density of 806.495 kg/m3 which falls within the high-density wood classification. The result of the field exposure test showed a moderate correlation with the density. The gravimetric weight loss assessment showed that the inner portion had higher weight loss than the outer portion of the wood, revealing a higher resistance to termite attack. In order to ensure a higher reliability of B. aethiopum wood in service, cant sawing method should be used to separate the less durable inner portion of the wood from the outer portion.
PASSIVE THERMAL CONTROL FOR BUILDINGS IN TEMPERATE REGIONS-COMPARISON OF CAVI...paperpublications3
Abstract: Providing thermal comfort without excess space and conditioning costs is one of the primary requirements of buildings. Therefore, thermal control is an important aspect in almost all buildings. Understanding heat transfer and the temperature distribution through building materials and assemblies is also important for assessing energy use. Thermal comfort, thermal movements, durability, and the potential for moisture problems. The control of heat flow in buildings requires insulation layers compromised with few thermal bridges, an effective air barrier system, good control of solar radiation, and management of interior heat generation. Walls play a huge role in the heat gain and loss in buildings, thus, making wall an important subject in passive thermal control in buildings. This article is aimed at analyzing cavity walls and solid brick walls and comparing them for home construction in temperate regions. Temperate regions need good insulating walls, thus reducing heat loss via walls to its minimal, which in turn reduces the cost of active heating measures in buildings.
Flexural Strength of Solid and Glue-Laminated Timber BeamsIJERA Editor
An investigation into the flexural strength of solid and laminated timber beams under working conditions was
conducted. Six locally available species, which consist of three hardwoods and three softwoods were
investigated, which were Berlina, Danta, Alstonia, Agba, Ohia, and Obeche. The dimension of the hardwoods
solid beams are 100mm×100mm×900mm and softwoods solid beams are 150mm×150mm×900mm. The result
showed that the density of Berlina is 0.00128g/mm3, Danta is 0.000903g/mm3, Alstonia is 0.00816g/mm3, Agba
is 0.000724g/mm2, Ohia is 0.000716g/mm3 and Obeche is 0.000568g/mm3 and the weight for Berlina was
11.58kg, Danta was 8.13kg, Alstonia was 7.75kg, Agba was 14.67kg, Ohia was 14.5kg and Obeche was 11.5kg.
Comparing it with the maximum load the species could carry, Berlina was 108kN, Danta was 85.0kN, Alstonia
was 66.0kN, Agba was 50.0kN, Ohia was 103kN and Obeche was 60.0kN. Futhermore, twenty-four (24)
laminated timber beams of the same dimensions were manufactured with six (6) different species, viz: Afara,
Okwen, Danta, Obeche, Alstonia, Bombax. These beams were glued together using top-bond gum and allowed
to dry for twenty-four hours after which they were weighed before testing. The twenty-four beams were tested
to failure and the deflection reading taken from the dial-guage. Finally, a curve of deflection against the load
was plotted. It can be seen that with a stress of 10.80N/mm2, 8.50N/mm2, 6.60N/mm2, 2.222N/mm2, 4.58N/mm2
and 2.67N/mm2 the design stress, deflection criteria cannot be ignored, after comparing result from the
experiment, limiting deflection and actual deflection. A theoretical and experimental correlation of strength
evaluation was established for glue solid and glue laminated beams which were formed from combining timber
with glue.
The Effects of Flooring Material on Thermal Comfort in a Comparative Study Marble and Parquet Flooring
https://uijrt.com/articles/v1i5/UIJRTV1I50004.pdf
An Experimental Investigations of Nusselt Number for Low Reynolds Number in a...IJMER
: In this paper, we present results of measured heat transfer coefficients for each sodium
carboxymethyl cellulose concentration at two different lengths of coil L=2.82m, L=2.362m and with
two different heat inputs 1.0kW and 1.5kW . Test solutions of sodium carboxymethyl cellulose
concentrations of 0.05%, 0.1%, 0.15% and 0.2% were used in our experimental runs. A four flat blade
paddle impeller was used to verify the mixed fluid, under steady heating of Newtonian and nonNewtonian
fluids in an flat bottom agitated vessel. A Kanthal Heating Element Equipment have been
design and fabricated to optimize the heating of the fluids in an agitated vessel. The rehogical properties
like flow behavior index, consistency index and viscosity data were carried experimentally using Rotating
Cylinder Method for all the test solutions. A correlations have been presented for Newtonian and non
Newtonian fluids in laminar flow conditions
On the low temperature resistivity measurement of CdSe thin filmijtsrd
Most group II-VI compounds are direct band gap semiconductors with high optical absorption and emission coefficients .Cadmium Selenide is a leading candidate with high potential towards many applications. The authors present their investigations dealing with preparation and some electrical characterization of the CdSe thin films. The films were deposited onto a well-cleaned glass substrates using thermal evaporation technique. The dependence of electrical resistivity of CdSe thin film in low temperature range has been studied. R.K.Shah | H.O.Parmar | H.S.Patel"On the low temperature resistivity measurement of CdSe thin film" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-1 | Issue-2 , February 2017, URL: http://www.ijtsrd.com/papers/ijtsrd65.pdf http://www.ijtsrd.com/other-scientific-research-area/physics/65/on--the-low-temperature-resistivity-measurement-of-cdse-thin-film/rkshah
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Collectors innovation to increase performance solar water heatereSAT Journals
Abstract There have been many studies to improve the performance of the solar water heater. The long term goal of research is to obtain scientific information, teaching materials and as the foundation of scientific development of energy conversion. The specific objective of this study is to find or develop new models and models that can improve the efficiency of the solar water heater. Research methods; research conducted using the experimental method, which is to test the amount of cover glass, flow rate and preheat a working fluid that can improve the efficiency of solar water heater. Research output: 1) The efficiency of the best solar water heater is the sum of three layers of glass cover compared to the cover glass number two layers and one layer, 2) The greater the water flow rate, the efficiency of the solar water heater increases, 3) initial heating on water entry, exit and cause the water temperature absorber plate temperature is relatively the same, so the efficiency of the solar water heater close to zero. Keywords: number of glass cover, flow rate, initial heating, solar water heater
The basic density and some of the anatomical
properties of five clones of Eucalyptus tereticornis developed
by ITC Bhadrachalam were reported. The five clones
represented by four trees each of four and half years old were
from Sarapaka, Andhra Pradesh. Within tree variation in
anatomical properties of four and half years old grown
Eucalyptus tereticornis clones have been investigated and
correlated with basic density. Anatomical parameters studied
were found to vary significantly from bottom to top with no
definite trend. Significant variation exists in all the five clones
of different parameters. Basic density was positively correlated
with fibre length at middle, top and pooled positions. Fibre
length was positively correlated with fibre diameter, fibre
lumen diameter at bottom position, and with vessel diameter at
middle position, and negatively correlated with vessel
frequency at top position. The results obtained in this study
have shown the suitability of raw material for paper and pulp
where the required basic density is met with. Mainly these
clone are primarily tried to meet the requirement of paper and
pulp industry
It is widely accepted that heat treatment of wood ameliorates its dimensional stability and color evolution. This study has analyzed the effects of heat treatment in color changes and hygroscopic properties of fir wood (Abies Borissi-regis Mattf.), exposed at 200º C for 2, 3 and 4h. Dimensional stability and absorption were measured after 1 day and 3 days immersion in water of 20 º C ± 3 temperature. Color evolution and color changes were analyzed in three different directions using the CIE L*a*b* color space. The results showed that heat treatment resulted in a darkened color and an improvement in the dimensional stability of wood. The visual changes in color were more distinct after 4h treatment. The total color differences (ΔΕ) of the surface of wood substrates appear to be directly correlated with the treatment time. Swelling percentage of the samples was found to be affected by the thermal treatment intensity. The higher percentage of swelling decrease was recorded at approximately 19.61% in 4h treatment duration in a tangential direction whereas, the lowest percentage of 0.54% was derived from 3h treatment duration in a radial direction.
Research of Physical Properties of Straw for Building Panelsinventionjournals
The development of new thermal insulation materials needs to evaluate properties and structure of raw materials, technological factors that make influence on the thermal conductivity of material. One of the most promising raw materials for production of insulation material is straw. The use of natural fibres as insulation is closely linked to the ecological building sector, where selection of materials is based on factors including recyclable, renewable raw materials and low resource production techniques. In current work results of research on structure, thermal conductivity, water vapour permeability and short term water immersion of triticale straw for production of thermal insulating straw panels are presented. Straw panels withdifferent densitywere prepared for thermal conductivity measurement. It was determined that lowest thermal conductivity of straw is reached when straw density ranges from 80kg/m3 to 120 kg/m3 . It was found that the macrostructure that changes with density increase has the great effect on thermal conductivity of materials. At the density range of 120-190 kg/m3 increase of thermal conductivity values are observed. Water vapour permeabilitywas analysed at the density ranges from 80 kg/m3 to 156 kg/m3 . Vapour permeability values grew with density increase from 2 to 2.5. Short term water absorption was evaluated by two parameters - as water absorption coefficient due to capillary action and short term water absorption by partial immersion. Water absorption coefficient shows sudden mass increase within the first 10 minutes and subsequent slow mass increase. Short term water absorption values show significant weight increase during 48 hours, which reaches 100 percent by mass
DETERMINATION OF THERMAL AND PHYSICAL PROPERTIES OF PALMYRA WOOD (BORASSUS AE...IAEME Publication
Palmyra or Borassus aethiopum Mart is a timber that is used in the traditional construction of housing and semi-modern yet its thermal characteristics are very little known. The aim of this work is to determine experimentally thermo physical characteristics of palmyra wood of Chad. In this contribution, we will determine the moisture content and density of the wood palmyra and we use the method of guarded hot plate to estimate the thermal conductivity in different parts of the specimen namely the Heart, and the sapwood duramen after reaching steady state. Given the results, we note that the thermal conductivity of palmyra wood depends on its anatomical structure and humidity. The lighter parts are more insulating and remain always with high humidity. Note also that the heat spreads more in the direction parallel to the fibers than perpendicular to the fibers.
THERMAL CONDUCTIVITY ANALYSIS IN VARIOUS MATERIALS USING COMPOSITE WALL APPAR...IAEME Publication
Heat transfer due to temperature difference and mass concentration difference as heat and mass transfer. So many research has been made in past on heat transfer through composite wall of different materials. Which I have extended this work by taking a new materials like a charcoal and natural gum as an composite material along with mild steel, Bakelite and wood. In which I conduct a experiment on a composite material wall apparatus and fitted mica heater plate centrally in the combination on the composite wall and varying the voltage at 80 , 120 ,160 and current is different so I found the thermal conductivity of the material as followed Bakelite – 0.976645 W/m-k , wood- 1.804670 W/m-k , charcoal- 0.272975 W/m-k, and natural gum – 0 according to the found result i hope the natural gum can be used as a insulating material in the future.
The need for vernacular mud huts of Ranchi to re-adapt in response to the cha...Janmejoy Gupta
presented at conference in SPA BHOPAL in Dec 2015...on vernacular architecture...
under the sub-head....Adaptation and innovation in Techniques of Construction for the Future of Vernacular Architecture.
The Art of the Pitch: WordPress Relationships and SalesLaura Byrne
Clients don’t know what they don’t know. What web solutions are right for them? How does WordPress come into the picture? How do you make sure you understand scope and timeline? What do you do if sometime changes?
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Epistemic Interaction - tuning interfaces to provide information for AI supportAlan Dix
Paper presented at SYNERGY workshop at AVI 2024, Genoa, Italy. 3rd June 2024
https://alandix.com/academic/papers/synergy2024-epistemic/
As machine learning integrates deeper into human-computer interactions, the concept of epistemic interaction emerges, aiming to refine these interactions to enhance system adaptability. This approach encourages minor, intentional adjustments in user behaviour to enrich the data available for system learning. This paper introduces epistemic interaction within the context of human-system communication, illustrating how deliberate interaction design can improve system understanding and adaptation. Through concrete examples, we demonstrate the potential of epistemic interaction to significantly advance human-computer interaction by leveraging intuitive human communication strategies to inform system design and functionality, offering a novel pathway for enriching user-system engagements.
Accelerate your Kubernetes clusters with Varnish CachingThijs Feryn
A presentation about the usage and availability of Varnish on Kubernetes. This talk explores the capabilities of Varnish caching and shows how to use the Varnish Helm chart to deploy it to Kubernetes.
This presentation was delivered at K8SUG Singapore. See https://feryn.eu/presentations/accelerate-your-kubernetes-clusters-with-varnish-caching-k8sug-singapore-28-2024 for more details.
Software Delivery At the Speed of AI: Inflectra Invests In AI-Powered QualityInflectra
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• Test Automation: How AI-powered test case generation, optimization, and self-healing tests are making testing more efficient and effective.
• Visual Testing: Explore the emerging capabilities of AI in visual testing and how it's set to revolutionize UI verification.
• Inflectra's AI Solutions: See demonstrations of Inflectra's cutting-edge AI tools like the ChatGPT plugin and Azure Open AI platform, designed to streamline your testing process.
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JMeter webinar - integration with InfluxDB and GrafanaRTTS
Watch this recorded webinar about real-time monitoring of application performance. See how to integrate Apache JMeter, the open-source leader in performance testing, with InfluxDB, the open-source time-series database, and Grafana, the open-source analytics and visualization application.
In this webinar, we will review the benefits of leveraging InfluxDB and Grafana when executing load tests and demonstrate how these tools are used to visualize performance metrics.
Length: 30 minutes
Session Overview
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During this webinar, we will cover the following topics while demonstrating the integrations of JMeter, InfluxDB and Grafana:
- What out-of-the-box solutions are available for real-time monitoring JMeter tests?
- What are the benefits of integrating InfluxDB and Grafana into the load testing stack?
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- Demonstration of InfluxDB and Grafana using a practice web application
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1. Insights into SAP testing best practices
2. Heatmap utilization for testing
3. Optimization of testing processes
4. Demo
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Execution from the test manager
Orchestrator execution result
Defect reporting
SAP heatmap example with demo
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Deepak Rai, Automation Practice Lead, Boundaryless Group and UiPath MVP
UiPath Test Automation using UiPath Test Suite series, part 4
Thermal conductivity of three different wood products of combretaceae family
1. Journal of Natural Sciences Research www.iiste.org
ISSN 2224-3186 (Paper) ISSN 2225-0921 (Online)
Vol.2, No.4, 2012
Thermal Conductivity of Three Different Wood Products of
Combretaceae Family; Terminalia superb, Terminalia ivorensis and
Quisqualis indica.
Oluyamo Sunday Samuel 1, 2, *, Bello Olawale Ramon2 and Yomade Olabode Johnson2
1 Department of Physical Sciences, Bells University of Technology, P.M.B, 1025, Ota, Nigeria
2 Department of Physics, Federal University of Technology, P.M.B. 704, Akure, Nigeria
*E-mail of the corresponding author: oluyamos@yahoo.com
Abstract
The uses of wood and wood based materials in everyday life ranging from domestic to industrial applications had
called for renewed updating of the information on various thermal properties of the materials at different stages. The
ability of wood materials to withstand shock and deformation depends basically on their thermal responses at
specific temperature and time. The study examines the thermal behavior of three wood species of the family of
combretaceae (Terminalia superb, Terminalia ivorensis and Quisqualis indica) using the modified Lee’s method.
Within an interval of time, the thermal agitation in the samples increases as the temperature increases, after which
thermal stability was attained. The thermal agitation is seen to be more prominent during the rising temperature than
at the falling temperature. All samples attained stability after about 105 minutes of continuous agitation during the
rising temperature and much more faster at the falling temperature. In addition, the thermal conductivity values
obtained for the samples fall within the general range of conductivity (0.1-0.8 Wm-1K-1) for wood materials.
Key words: Wood materials, thermal conductivity, Lee’s method, temperature and time.
1. Introduction
Thermal conductivity is a measure of the rate of heat flow through one unit thickness of a material subject to a
temperature gradient. Wood exhibits low thermal conductivity (high heat-insulating capacity) compared with
materials such as metals, marble, glass, and concrete. Thermal conductivity is highest in the axial direction and
increases with density. Wood is one of the most useful materials touching the history of man and his environment
especially in the provision of shelter (the habitation of man), tools, weapons, furniture, packaging, artworks, and
paper (Ahn et al, 2009; Wag and Kumaran 1999). In fact, wood is one of the materials used to achieve some of the
basic needs of man. Wood has different properties ranging from specie to specie. Although wood expands and
contracts with varying temperature, these dimensional changes are small compared with shrinkage and swelling
caused by varying moisture content. In most cases, such temperature-related expansion and contraction are negligible
and without practical importance. Only temperatures below 0 °C (32 °F) have the potential to cause surface checks;
in living trees, unequal contraction of outer and inner layers may result in frost cracks.
The use of wooden materials for numerous purposes cannot be over emphasized. Various researches had been carried
out on these materials at different stages and conditions. A systematic investigation of the variation in the
hygrothermal properties of several wood-based building products investigated by (Kumaran 2003 et al) revealed a
new information on the variations of thermal conductivity, water vapour permeability, moisture diffusivity, water
absorption coefficient and air permeability of some classes of wood products. The research also presents detailed
description of a range of properties such as the density and temperature dependences of thermal conductivity,
dependence of vapour resistance factor on relative humidity, dependence of moisture diffusivity on moisture
concentration, equilibrium moisture content for the full range of relative humidity, variations in the water absorption
coefficients and dependence of air permeability on pressure difference. The development of hygrothermal computer
models which have become powerful tools for building scientist and building practitioners alike had been
acknowledged to require a set of reliable inputs to yield meaningful results (Hens 1996; Kumaran 1996;, Trechel
2001)
As building materials evolve, there is a need for continuous updating of the information on various thermal
properties of wood products. Researches (Kumaran et al 2002a; Kumaran et al 2002b) conducted at the Institute for
Research in Construction generated detailed information on the hygrothermal properties of more than 70 building
products that are currently used in Canada and the United States of America. These researches specifically looked at
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2. Journal of Natural Sciences Research www.iiste.org
ISSN 2224-3186 (Paper) ISSN 2225-0921 (Online)
Vol.2, No.4, 2012
the ranges of the thermal properties by contemporary products in North America. The products chosen included
wood and wood based materials, bricks, mortar, stucco and building membranes. Information on wood-based
products such as Oriented Strand Board (OSB), plywood, wood fibre-board and wood siding were also reported.
Thermal conductivity is a critical attribute when offering energy conserving building products. This is due to the fact
that wood has excellent heat insulation properties. Lower thermal conductivity values equates to greater heat
insulating properties (Daniel 2010). The prevalence of wood product in construction industries is driven by their high
stiffness to weight ratio allowing for the use of lightweight assemblies and innovative design. However, field
experience suggests that fire performance on engineered wood products is inferior to traditional timber (Mahmood).
Wood plastic composites (WPC) (i.e. composites from materials from wood and thermo plastically processable
matrices) is known to have drawn increasing attention over the years. To this end, wood materials had been preferred
to inorganic materials like talcum or fibre due to the density of the composite, which is considerable lower and
therefore of interest for transportation applications, as well as the renewability and enhanced recyclability of the
wood plastic composites (Daniel 2003; Burgstaller 2006; Burgstaller 2007). The influence of processing parameters
e.g. throughput and temperature of the compounding step of wood plastic composites and bamboo blast were
investigated by (Vanchai 2010; Li et al 1995). The effects on the mechanical properties, colour of the produced
composites correlated with the different processing parameters showed a wide range of good processability, only at
high temperature and low throughput strong darkening occurred, as well as loss of tensile strength was found for the
samples in the study.
Hitherto, available studies in the literatures are mainly concerned with the relationship between the thermal
conductivity of the materials with some processing parameters such as temperature, strength, density etc. As a result,
some salient properties like the therrmal behavior with the temperature and within some time interval are not
investigated. In this study therefore, the conductivity as well as the thermal behaviour of three different wood species
found and utilized in the environment of the research are examined at different regimes of temperature and time. This
is necessary for wood/building engineers to be able to effectively categorise these species materials by virtue of their
thermal behaviour within given temperature range and time.
2. Materials and method
The materials used in the study include three different wood species growing in the rainforest region, South Western
Nigeria (Terminalia superb, Terminalia ivorensis and Quisqualis indica) of the family of Combretaceae. The samples
used were obtained in the sizes of 0.3x0.3 and 0.3x0.5 inches and about 8.0 inches long. These were machined down
to about the same diameter of the Lee disc (i.e. 40mm) and 4mm thickness. The surfaces of the samples were also
smoothened for good thermal contacts. The basic apparatus used was a modification of the standard Lees’ disc
method for the measurement of thermal conductivity by the absolute plane parallel plate technique (Griffin 2002;
Duncan 2000). This consists of three brass discs A, B, and C drilled to accept liquid-in-glass thermometers and a 6W
electrical plate heater of the same diameter as the discs. Each sample was placed between discs A and B one after the
other. The heater was sandwiched between discs B and C and, after tightening the clamp screw to hold all the discs
together. The set-up was connected to a DC power supply. The whole assembly was placed in an enclosure to
minimize the effects of draughts. A thermometer was placed close to the apparatus, to measure the ambient
temperature. The complete set-up is shown in figure 1. At the beginning of each determination, the voltage from the
stabilized Direct Current supply was set on to about 6.0V while the temperatures of the discs (i.e. the temperatures of
plates A, B and C) were monitored until the temperature of disc A attained a desired value of 50oC. This took several
hours. Readings were taken at 15 minutes intervals during this period. At this stage, the Voltage supply was reduced
and temperature readings of the discs were monitored at every 5 minutes interval. In order to effectively analyse the
thermal agitation in the samples, the thermal conductivity were estimated at every 15 minutes interval up to a point at
which the temperatures of the discs had stabilised to within ±0.1°C for at least 30 minutes. The value for the thermal
conductivity ( λ ) of each sample of thickness d and radius r was estimated from the relation.
ed T A + TB
λ= a S + 2 a AT A
2πr (TB − TA )
2
2 (1)
where e is given by
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3. Journal of Natural Sciences Research www.iiste.org
ISSN 2224-3186 (Paper) ISSN 2225-0921 (Online)
Vol.2, No.4, 2012
VI
e= (2)
T A + TB
a A T A + a S + a B TB + a C T
2
and
a A = aC = πr 2 + 2πrld
aB = 2πrld (3)
as = 2πrl s
were ld andls are the thicknesses of disc and sample, while , , , and are the exposed surface areas of
discs A, B, C and the specimen respectively. , and are the temperatures of the discs A, B and C above
ambient (i.e. the thermal equilibrium temperature of the disc minus the ambient temperature). V is the potential
difference across the heater and I is the current which flows through it. In order to fully analyse the thermal
behaviour of the samples within the temperature range, a MATLAB programme was written to compute the thermal
conductivities at given time interval.
3. Results and Discussion
The result of the direct measurements of the samples at different current-voltage stages are shown in tables 1-3 for
both rising and falling temperatures. The temperatures of the discs increase as the time increases up to stability for
each disc. In addition, slight increase was noticed for the ambient temperature. This could be attributed to increase in
environmental activities at the vicinity of the experiment. The increase in temperature with time results to gradual
decrease in the thermal conductivity of the samples to equilibrium values. This feature was also noticed for the
falling temperature with a gradual increase in thermal conductivity to stability..
Figures 2-4 show the variation of the thermal conductivities with time for the three samples. The thermal agitation of
the samples was found to increase gradually and approaches stability with time. The samples attained equilibrium
after about 105 minutes of continuous agitation. This equilibrium values suggests the thermal conductivities of the
various samples. The rate at which thermal equilibrium was attained was found to be faster at the falling temperature
than for the rising temperature. This effect could be attributed to the fact that initially, enough energy is required to
break the bonds of the particles in the samples and on reaching their maximum excited positions, and as the thermal
energy reduces, the particles tend to return to their mean position. Hence withdrawal of heat from the system would
course the particles to return back to their mean position faster and more regular than when the temperature was
rising. It is evident that as the temperature of the samples increases the particles receive thermal agitation and thereby
are scattered away from their equilibrium position. This is more prominent at the rising temperature.
Figure 5 shows the variation of the thermal conductivities of the three samples with time. The Terminalia superba
exhibits the highest thermal agitation followed by Terminalia invoresis while Quisqualis indica had the lowest
thermal agitation. According to [10], the thermal properties of wood vary with species type with conductivity values
generally in the range of 0.1-0.8 Wm-1K-1. The values of the thermal conductivities obtained in this report conform
with this result. They are also found to possess good thermal behaviour. However, the Terminalia wood types have
both higher thermal agitation and conductivities than the Quisqualis type.
4. Conclusion
The prevalence of different wood products in the society especially in the construction industry calls for concerted
efforts to examine the various thermal responses of these materials to stress and other environmental conditions. In
addition as building materials evolve, there is need for continuous updating of the information on their thermal
properties. This would assist building engineers in the choice of construction material to adopt for effective use. The
wood materials in this study have been sourced from the immediate vicinity of the research. The thermal properties
of three different species (Terminalia superb, Terminalia ivorensis and Quisqualis indica) of the family of
Combretacea were examined in the study. The results obtained revealed that the wood materials in the study possess
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Vol.2, No.4, 2012
good thermal properties. The thermal conductivities values for the samples were found to conform with the general
range of conductivity for wood materials.
References
Ahn, H. K., Sauer, T. J., Richard, T. L., Glanville, T. D. (2009) “Determination of the thermal properties of
composting builking materials”, Bioresource Technology, 100, 3974-3981
Wag, J., Kumaran, M. K. (1999) “How well should one know the hygrothermal properties of building materials”
Proceedings of CIB WICO meeting, Pragne, Czech Republic, Pp 47-52
Kumaran, M. K., Lackey, J. C,, Normandin, N., Tariku, F., Reenen, D. V. ( 2003) “Variation in the hygrothermal
properties of several wood based building products” Research in Building Physics, Leuven Belgium, pp 35-42
Hens H 1996 Heat, Air and Moisture Transfer in Insulated Envelope Parts. Final Report, Volume 1, Task 1:
Modelling. International Energy Agency Annex 24, Laboratorium Bouwfysica, K. U. -Leuven, Belgium.
Kumaran, M. K. (1996) “Heat, Air and Moisture Transferring insulated Envelope” Final Report, Vol 3, Task 3,
Materials Properties. International Energy Agency Annex 24, Laboratorium Bourfysica, K. U.-Leuren, Bergium
Trechsel, H. R. (ed) 2001 “Moisture Analysis and Condensation control in building envelopes” ASTM MNL40,
Appendices A to K, 161-184
Kumaran, M. K., Lackey, J. C., Normandin, N., Reemen, Van D. Tariku, F. (2002a) “Summary report from Task 3
of MEWS project”. Institute for Research in Construction, N. R. C, Canada (NRCC-45369), Pp. 68
Kumaran, M. K., Lackey, J. C., Normandin, N., Reemen, Van D. Tariku, F. ( 2002b) “A thermal and moisture
transport property database for common building and insulating materials” ASHRAE website, Research Project
Report 1018-RP
Daniel, D. P. (2010) “Perfect ! Wood Win-Door Profiles”, Trace Laboratories, INC 5 North Park Drive Hunt Valley,
MD 21030, USA. Pp 1-5
Mahmood, Tabaddor (2008) “Thermal and Mechanical Finite Element Modeling of Wood-Floor Assemblies
Subjected to Furnace Exposure” Underwriters Laboratory, 07CA42520, NC9140
Daniel, M. (2005) “Wood Plastic Deposite in Europe Vs USA-processing and product trends” Proceedings ‘Wood
plastic composite 2005’. Applied marketing information, Vienna
Burgstaller, Christopher (2006) “Investigation on the relationship between wood particle size, wood type and content
on the mechanical and physical properties of wood platic composites”. Doctoral thesis, Johannes Kepler University,
Linz, p 25
Burgstaller, Christopher (2007) “Processing of thermal sensitive materials-a case study of wood plastic composites”
Monatschefte fur Chemie 138, 34-346
Vanchai, Laemlaksakul (2010) “Physical and Mechanical properties of particle board from Bamboo waste” World
Academy of Science, Engineering and Technology, 64
Li, S. H., Zeng, Q. Y., Xio, Y. L., Fu, S. Y., Zhou, B. L. (1995)”Biomimicry of bamboo bast fire with engineering
composite materials”. Mater. Sci. Eng., 3, 125-130
Griffin and George (2002) ‘Lees’ Conductivity Apparatus (Electrical Method)” LL44-590 I.S. 1122/7302, Griffin
& George Ltd., Wembley, Middlesex UK. Pp 2-4
Duncan, M. P., Mark, J. (2000) “Thermal Conductivity of PTFE and PTFE Composites’ IPTME, Loughborough
University, Loughborough, UK. Pp. 580-581
Acknowledgement
The authors would like to appreciate the Metallurgical and Materials Engineering processing Laboratory of the
Federal University of Technology, Akure, Nigeria for the assistance rendered during the preparation of the samples.
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Vol.2, No.4, 2012
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6. Journal of Natural Sciences Research www.iiste.org
ISSN 2224-3186 (Paper) ISSN 2225-0921 (Online)
Vol.2, No.4, 2012
Figure 1. Schematic diagram of the Lee’s Disc apparatus used for the measurement of the
samples.
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ISSN 2224-3186 (Paper) ISSN 2225-0921 (Online)
Vol.2, No.4, 2012
Rising tem perature
Falling tem perature
1.2
K )
1.0
-1
-1 0
Thermal Conductivity (Wm
0.8
0.6
0.4
0.2
0.0
0 20 40 60 80 100 120
Tim e/minutes
Figure 2. Variation of thermal conductivity of Terminalia superba’s sample with time
R is in g te m p e ra tu re
0 .3 0 F a llin g te m p e ra tu re
0 .2 8
0 .2 6
K )
-1
-1 0
0 .2 4
Thermal Conductivity (Wm
0 .2 2
0 .2 0
0 .1 8
0 .1 6
0 .1 4
0 .1 2
0 20 40 60 80 100 120
T im e /m in u te s
Figure 3. Variation of thermal conductivity of Terminalia ivorensis’s sample with time
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8. Journal of Natural Sciences Research www.iiste.org
ISSN 2224-3186 (Paper) ISSN 2225-0921 (Online)
Vol.2, No.4, 2012
Rising tem perature
0.30 Falling tem perature
0.28
0.26
K )
-1
0.24
-1 0
Thermal Conductivity (Wm
0.22
0.20
0.18
0.16
0.14
0.12
0.10
-20 0 20 40 60 80 100 120 140 160
Time/m inutes
Figure 4. Variation of thermal conductivity of Quisqualis indica’s sample with time
Terminalia Superba
Terminalia Ivorensis
Quisqualis Indica
0.30
K )
-1
-1 0
0.25
Thermal Conductivity (Wm
0.20
0.15
0.10
0 20 40 60 80 100 120
Tim e/m inutes
Figure 5. Variation of the thermal conductivity of the three samples with time
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