Types Of Insulation Materials Research Articles

Impact of Phase Change Material (Butyl Stearate) and other insulation material on thermal performance of building envelope in different climates of India

India is a developing country and thus has to cater to high energy demands in both rural and urban areas. Buildings and construction together account for 36% of global final energy use and 39% of energy-related carbon dioxide (CO2) emissions when upstream power generation is included. In India, the building sector consumes around 30% of the total energy. This research work is divided into two parts. The first one is the comparative evaluation of insulation materials for optimization of energy, and the other one is direct encapsulation of PCM material into the wall. The selection of building insulation materials such as EPS, XPS, PUF, GW and RW etc is based on market availability and suitability to weather conditions at building location. The Indian weather conditions have been classified into 6 different categories as per ISHRAE namely hot and dry, warm and humid, moderate, cold and cloudy, cold and sunny, and composite and similarly classified as Very Hot–Humid (1A), Dry (1B) as per ASHRAE 90.1 2007. Five locations of India with different climatic conditions have been chosen covering all Indian climatic zones which are Delhi (composite), Mumbai (Warm & Humid), Ahmedabad (Hot & Dry), Bangalore (Composite), and Srinagar (Cold). Selected types of insulation materials have been tested for thermal load performance of the building envelope in each of the above weather conditions including life cycle cost (LCC) analysis for 20 year period, carried out to select the best alternative amongst the selected insulation materials for each of the weather conditions. The parameters for the selection of insulation material are based not only on saving energy but also on protecting the environment from harmful gases. In Delhi state, The best suitable insulation material is RW since its payback is 1.08 years with maximum energy saving of 17.82%. In the case of Ahmedabad, GW gives maximum energy saving with optimum thickness, but the payback period is much lesser for Rock Wool viz.,1.06 years. In the case of Bangalore, the suitable material is RW with the payback period of 1.84 years. For Mumbai city, RW is the optimum material with a payback period of 2.02 years.

Optimising Embodied Energy and Thermal Performance of Thermal Insulation in Building Envelopes via an Automated Building Information Modelling (BIM) Tool

Insulation systems for the floor, roof, and external walls play a prominent role in providing a thermal barrier for the building envelope. Design decisions made for the insulation material type and thickness can alleviate potential impacts on the embodied energy and improve the building thermal performance. This design problem is often addressed using a building information modelling (BIM)-integrated optimisation approach. However, one major weakness that lies in the current studies is that BIM is merely used as the source for design parameters input. This study proposes a BIM-based envelope insulation optimisation design tool using a common software Revit and its extension Dynamo to find the trade-off between the total embodied energy of the insulation system and the thermal performance of the envelope by considering the material type and thickness. In addition, the tool also permits data visualisation in a BIM environment, and automates subsequent material library mapping and instantiates the optimal insulation designs. The framework is tested on a case study based in Sydney, Australia. By analysing sample designs from the Pareto front, it is found that slight improvement in the thermal performance (1.3399 to 1.2112 GJ/m2) would cause the embodied energy to increase by more than 50 times.

Optimizing environmental insulation thickness of buildings with CHP-based district heating system based on amount of energy and energy grade

The increase of insulation thickness (IT) results in the decrease of the heat demand and heat medium temperature. A mathematical model on the optimum environmental insulation thickness (OEIT) for minimizing the annual total environmental impact was established based on the amount of energy and energy grade reduction. Besides, a case study was conducted based on a residential community with a combined heat and power (CHP)-based district heating system (DHS) in Tianjin, China. Moreover, the effect of IT on heat demand, heat medium temperature, exhaust heat, extracted heat, coal consumption, carbon dioxide (CO2) emissions and sulfur dioxide (SO2) emissions as well as the effect of three types of insulation materials (i.e., expanded polystyrene, rock wool and glass wool) on the OEIT and minimum annual total environmental impact were studied. The results reveal that the optimization model can be used to determine the OEIT. When the OEIT of expanded polystyrene, rock wool and glass wool is used, the annual total environmental impact can be reduced by 84.563%, 83.211%, and 86.104%, respectively. It can be found that glass wool is more beneficial to the environment compared with expanded polystyrene and rock wool.

First-Principles Study of Ultrathin Single-Walled Nanotube-Based Single-Electron Transistor for Fast-Switching Applications

This work presents modeling and functioning of nanotube island single-electron transistor (SET), through first-principles approach based on density functional theory and non-equilibrium Green’s function. Ultrathin single-walled carbon (C), boron nitride (BN), and silicon carbide (SiC) nanotubes in armchair (3, 3) and zigzag (5, 0) structures have been adopted as island in the SET model. The nanotube (NT) islands are weakly coupled to gold metal electrode, explained by sequential transport phenomenon. Present study evaluates ionization energies, electron affinities, and additional energies for all the considered NTs in both isolated and SET environment, which are further analyzed by plotting total energies and Coulomb blockade diagrams. Also, various types of dielectric material and their thickness have been investigated, owing to measuring the stability of charge as well as dependence of conductance on gate and source-drain voltage. Observed results show noticeably enhanced conductance for ultrathin single-walled C, BN, and SiC zigzag NTs than that of their corresponding armchair NTs in the SET systems, demonstrating their potential for fast-switching device applications.

ANALISIS KONDUKTIVITAS PANAS PADA MATERIAL ALTERNATIF SEBAGAI INSULASI DINDING RUANG AKOMODASI KAPAL BERBASIS LIMBAH AMPAS TEBU DAN SERBUK KAYU

The accommodation room on the ship is used as a resting place for the crew and as a storage place for goods on the ship so insulation is needed in each room to withstand the heat propagation on the ship. One type of insulation material on a ship is mineral wool which is made from polyurethane. Polyurethane is a plastic foam that is a mixture of polyol and isocynate and one of the ingredients is polymer which can be obtained from natural materials that contain lots of cellulose such as bagasse and sawdust. the addition of sawdust and bagasse that can be done is 40% of the total volume of the mixture. Then it is carried out to get the thermal conductivity value of each mixture of sawdust, bagasse, and polyurethane with various dosing ratios on the sawdust, to further calculate the cooling load. The test results show the best conductivity value is the mixing of wood powder 0.2 gr which is 2.65 w / mk which can withstand the rate of heat up to 311.59 KW.

A New and Compact Wide-Band Microstrip Filter-Antenna Design for 2.4 GHz ISM Band and 4G Applications

A new and compact four-pole wide-band planar filter-antenna design is proposed in this article. The effect of the dielectric material type on the characteristics of the design is also investigated and presented. The filter-antenna structure is formed by a fourth-order planar band-pass filter (BPF) cascaded with a monopole microstrip antenna. The designed filter-antenna operates at a centre frequency of 2.4 GHz and has a relatively wide-band impedance bandwidth of about 1.22 GHz and a fractional bandwidth (FBW) of about 50%. The effects of three different types of substrate material, which are Rogers RT5880, Rogers RO3003, and FR-4, are investigated and presented using the same configuration. The filter-antenna design is simulated and optimised using computer simulation technology (CST) software and is fabricated and measured using a Rogers RT5880 substrate with a height (h) of 0.81 mm, a dielectric constant of 2.2, and a loss tangent of 0.0009. The structure is printed on a compact size of 0.32 λ0 × 0.30 λ0, where λ0 is the free-space wavelength at the centre frequency. A good agreement is obtained between the simulation and measurement performance. The designed filter-antenna with the achieved performance can find different applications for 2.4 GHz ISM band and 4G wireless communications.

EXPERIMENTAL STUDY OF CHLORIDE-INDUCED STRESS CORROSION CRACKING (CISCC) FOR AUSTENITIC SUS 304L UNDER THERMAL INSULATION

Chloride-Induced Stress Corrosion Cracking (CISCC) has been frequently reported in the petrochemical industries where it usually causes failure to the austenitic stainless steel structures encased with thermal insulation in a chloride-containing environment. This study aims to analyze and evaluate the risk of chloride concentration and different types of insulation materials on CISCC of Austenitic SUS 304L. The experimental study was carried out for 14 days using U-bend specimens through the Drip Test apparatus, as per ASTM G30 and ASTM C692. U-Bend specimens were installed onto the test rig and shielded with different insulation materials. Sodium chloride (NaCl) salt solutions were periodically dripped onto the specimens, to simulate the wet and dry cycle. Insulation materials used were rockwool, calcium silicate and perlite, whereas the concentrations of NaCl solutions were set at 0.1, 1.0 and 3.5 wt.%. The specimens were inspected usingdye penetration tests (DPT), stereo microscope and optical microscope throughout the study to determine the CISCC susceptibility. Results showed that cracking was observed on the specimen with rockwool insulation at 3.5 wt% NaCl and 90°C. Rockwool has a high water absorption capacity at which saltwater will evaporate when in contact with a hot metal surface, resulting in the build-up of salt deposits of high concentration over time. SCC was not observed on other specimens with different conditions, but salt deposits, general corrosion and pitting corrosion were found. From the study, the thermal insulation of rockwool was found to have the highest tendency to cause SCC, followed by calcium silicate and perlite.Keywords: SUS304L, chloride-induced stress corrosion cracking, insulation materials, U-Bend specimen, drip test

Effect of strontium doping on the structural and dielectric properties of YCrO3

Study of multiferroic Y1−xSrxCrO3 (x = 0.0, 0.1) chromite obtained through solid-state reaction technique is presented. The Rietveld refinement of the XRD profile shows the orthorhombic Pbnm crystal symmetry of the system. The bandgaps of YCrO3 and Y0.9Sr0.1CrO3 samples are found as ~ 2.31 and ~ 2.23 eV, respectively. The FTIR spectra peaks show a red shift in the case of Sr2+ ion doping in YCrO3 indicating the reduction in cell volume. Two dielectric relaxation peaks are observed in the YCrO3 , whereas Y0.9Sr0.1CrO3 shows only one broad peak that is found to be extremely frequency dependent. The dielectric peak maxima shifts to higher temperatures with an increase in frequency in both the samples. This kind of dielectric variation is indicating a relaxor type of dielectric material. It is noted that the observed conductive process is closely associated with thermally stimulated oxygen vacancies. The P–E loops of both the samples have completely round shape with maximum polarization (Pmax) being observed at zero electric field. For YCrO3, the mechanism of leakage current conduction is in good agreement with the Ohmic conduction mechanism, whereas Y0.9Sr0.1CrO3 agrees well with space charge-limited conduction mechanism. The decreased bandgap and leakage current makes the Sr2+ ion doping beneficial for various electronic applications.

Tests of thermal insulation properties of bakelite and glass-epoxy composite

This paper presents tests results of thermal insulation of bakielite and epoxy resin with glass fibre. The tests were carried for the same thicknesses of different type of insulation materials and taking over the temperature through a steel plate under insolated material was measured. Based on the tests results material with better thermal insulation properties was chosen.

A REVIEW OF STUDY AND PERFORMANCE OF PARTIAL DISCHARGE FOR DIFFERENT TYPE OF INSULATION MATERIALS

The insulation should be high quality for power transmission and high voltage application, in this way we are studying about the various type of insulation material such as epoxy resin, vulcanized fibres and polyethylene which are having different capacitance value, the power transmission equipment’s has less efficiency due to degradation of insulation material. In this paper, we are studying the partial discharge for the different type of insulation materials.

Thin Films in Triboelectric Nanogenerators for Blue Energy Harvesting: Fabrication, Characterization, and Modeling

Renewable energy attracts many researchers as the non-renewable one has negative environmental impacts and limited availability. One of the main types of renewable energy is the blue energy where electricity is generated by water waves using triboelectric nanogenerators (TENGs). Thin films play an important role in the performance and therefore the efficiency of TENGs as they represent the electrodes between which electrons move producing electricity. In order to increase the generated electricity from TENGs, the properties of these electrodes should be modified. Therefore, in this paper, nano- and micro-size thin films are fabricated and characterized by measuring the geometrical parameters and electrical properties. Thin films are fabricated using aluminum with thicknesses 0.5 μm and 1.5 μm on acrylic substrate and 0.5 μm copper film on different types of dielectric materials including PVC and polystyrene. Atomic force microscopy is used to measure the geometrical parameters of the fabricated films including thickness and surface roughness. Also, Gwyddion software is used for the grain size evaluation. On the other hand, Keithley is used for measuring the electrical properties including electrical conductivity and sheet resistance. It is found that the electrical conductivity of aluminum films is inversely proportional to the thickness. The corresponding measured values of the electrical conductivity of the fabricated thinner and thicker aluminum films equal 1.7 x 107 (Ω.m)-1 and 1.4×107 (Ω.m)-1, respectively. Whereas, the electrical conductivity of the fabricated copper film equals 8.8×107 (Ω.m)-1. In addition, the temperature effects on the electrical conductivity are studied. Finally, simulation of a TENG using COMSOL software is accomplished in order to evaluate the electrical outputs of potential, charge, and energy.

Cooling performance of a thermal energy storage-based portable box for cold chain applications

Cooling performance of a portable box integrating with phase change material (PCM)-based cold thermal energy storage (TES) modules was studied and reported in this paper. The effects of locations of the PCM modules, melting point of the PCM, and insulation materials on the cooling duration of the box were numerically investigated with an experimentally validated model. Five configurations of PCM modules inside the box were examined: Case 1 - 100 % of the PCM located at the top; Case 2 - 20 % at the top and 20 % on each of side walls; Case 3 - 25 % on each of the side walls; Case 4 - 20 % on each of the side walls and 20 % at the bottom; and Case 5 - 100 % at the bottom. Five different PCMs with melting points at 2 °C, 3 °C, 4 °C, 5 °C and 8 °C were considered. A comparison was made between two different insulation materials (polyurethane, vacuum insulated panels) on the cooling performance. It was found that the configuration of PCM modules, the PCM melting point, and the type of insulation material all affected the cooling durations. The configuration of PCM with 20 % located at the top and 20 % on each of the side walls, with the melting point at 2 °C and the vacuum insulated panel (VIP) gave the longest duration time. The maximum cooling time was up to 46.5 h with the maximum discharging efficiency at 90.7 % and the highest discharging depth at 99.4 %, offering a great potnetial for cold chain applications.

Influence of Horizontal and Vertical Barriers on Fire Development for Ventilated Fa\xe7ades

Although using various innovative materials for ventilated facade systems positively contribute to the energy efficiency of buildings, the application of such materials can also pose a certain risk of fire propagation through the façade. In the last decade, medium and large-scale tests, as well as numerical analysis have been performed to assess the impact of fire barriers on fire propagation through ventilated façades. However, the number of fire barriers and their specific positions can also have an effect on the fire safety of facades, which has not been studied. Consequently, the question arises whether real fire exposure on a façade can be adequately simulated and analysed in sufficient detail, by using large-scale testing methods. This paper aims to conduct a parametric analysis on a broader range of large-scale samples by using the procedure given in the standard BS 8414-1:2015 + A1:2017. To understand better the impact of the number and position of cavity barriers for different types of insulation materials (stone wool/PIR/phenolic foam) used in modern façade systems with non-combustible cladding (ACM-A2). Seven tests were carried out in Croatia between October 2017 and April 2018. In the case of combustible insulation, two horizontal barriers were insufficient in preventing fire propagation. Temperatures accumulated above 600°C, reaching 840°C in PIR insulation and 979°C in phenolic foam insulation. For the same sample designed with non-combustible insulation, the maximum temperature measured was 133°C. Facades with combustible insulation passed the test only when four horizontal barriers were used. The existence of vertical barriers had a positive impact on preventing the fire propagation because the insulation on the left side of the chamber, behind the vertical barrier, remained undamaged. Vertical barriers on the right side of the chamber delayed the horizontal fire propagation from the main wall to the wing wall depending on the type of insulation. The results from these tests can serve as a basis for future research on the effects of fire barriers on fire propagation.

CSRR-Based Microwave Sensor for Dielectric Materials Characterization Applied to Soil Water Content Determination.

A new and compact sensor based on the complementary split-ring resonator (CSRR) structure is proposed to characterize the relative permittivity of various dielectric materials, enabling the determination of soil water content (SWC). The proposed sensor consists of a circular microstrip patch antenna supporting a 3D-printed small cylindrical container made out of Acrylonitrile-Butadiene-Styrene (ABS) filament. The principle of operation is based on the shifting of two of the antenna resonant frequencies caused by changing the relative permittivity of the material under test (MUT). Simulations are performed enabling the development of an empirical model of analysis. The sensitivity of the sensor is investigated and its effectiveness is analyzed by characterizing typical dielectric materials. The proposed sensor, which can be applied to characterize different types of dielectric materials, is used to determine the percentage of water contained in different soil types. Prototypes are fabricated and measured and the obtained results are compared with results from other research works, to validate the proposed sensor effectiveness. Moreover, the sensor was used to determine the percentage of water concentration in quartz sand and red clay samples.

APLIKÁCIA ANALYTICKEJ VIACÚROVŇOVEJ METÓDY PRI VÝBERE ZATEPĽOVACIEHO MATERIÁLU

The article deals with the selection of four types of insulation material based on the particular criteria. Specifically, it will be a matter of decision among facade insulation materials. We chose four species of the most used thermal insulation materials that are available on the market and are used frequently. The applied method is an analytical multilevel method that allows us to divide the whole problem into hierarchies and then compare two elements together and thus gain the weights of the criteria. Subsequently, we assessed the alternatives. The selected criteria are the price of the material, the thermal coefficient conductivity, flammability class and ignition time of the sample. The method is verified in the software BPMSG AHP priority calculator.

Análise de revestimento dielétrico de um sensor UHF de microfita aplicado na detecção de descargas parciais em transformadores de potência

<p class="Normal1">The use of UHF sensors in high voltage electrical equipment for monitoring its insulation system is widely used. In order to improve these sensors,we present an analysis of different types of dielectric materials that can be used as physical coating and shield, which can enhance the electromagnetic characteristics of UHF microstrip sensors applied to the detection of partial discharges in performance transformers. The materials used as coating were glass, silicone, FR4, Teflon, and acrylic. In order to do so,, HFSS software simulations for the development of analyzes on two UHF microstrip antennas were performed. From the analyzes performed, it was verified the improvement of the reflection coefficient and the gain of the UHF sensor recorded the materials used to demonstrate the practical application. In addition to that, we also had simulations of a typical electromagnetic shield applied in conjunction with the sensor to demonstrate that the shield is still displayed in the design stages and is of great relevance. In order to underpin the data obtained from the simulations, the real models of UHF sensors were applied and tested in the laboratory.</p>

Preparation and distinguish dielectric properties of multi-layer nanoparticles-based polyimide films

Insulation structure of inverter fed motors, mainly used in high-speed railways undergo continuous stresses of short pulses, making it difficult to maintain the insulation strength. Core–shell type of dielectric material and deposition of multilayer nanocomposite structures are being utilized in modern research to enhance the mechanical and dielectric strength of motor insulation. There is a high demand to explore electrical properties of such multilayer structure possessing thin dielectric layers of nanometric dimensions particles. The electrical performance of single-layer (polyimide/nano) and three-layer structure (nano-polyimide-nano) consisting of two different types of nano particles (Al2O3 and SiO2) are investigated, and results are compared with each other as well as with single layer structure. The structural interface and physical properties of dispersion of nano additive layers on polyimide are studied by microscopic analysis and other features such as weight loss, dielectric spectroscopy, and electrical and mechanical breakdown strength are also analyzed. Results showed that the three-layer structure with SiO2 additive have higher electrical breakdown strength compared with other types, 40% increase compared with single-layer nanofilms, 30% enhancement compared with three-layer Al2O3-PI-Al2O3 films. Besides, notable variations in results are observed at higher temperatures. The current research study on the basis of type, size and structure of sample will help manufacturers especially in the field of motor industry to select nano reinforced PI film according to industrial application.

Genetic Algorithm Applied to Multi-Criteria Selection of Thermal Insulation on Industrial Shed Roof

The rational use of energy has motivated research on improving the energy efficiency of buildings, which are responsible for a large share of world consumption. A strategy to achieve this goal is the application of optimized thermal insulation on a building envelope to avoid thermal exchanges with the external environment, reducing the use of heating, ventilation and air-conditioning (HVAC) systems. In order to contribute to the best choice of insulation applied to an industrial shed roof, this study aims to provide an optimization tool to assist this process. Beyond the thermal comfort and cost of the insulation, some hygrothermic properties also have been analysed to obtain the best insulation option. To implement this optimization technique, several thermo-energetic simulations of an industrial shed were performed using the Domus software, applying 4 types of insulation material (polyurethane, expanded polystyrene, rockwool and glass wool) on the roof. Ten thicknesses ranging from 0.5 cm to 5 cm were considered, with the purpose of obtaining different thermal comfort indexes (PPD, predicted percentage dissatisfied). Posteriorly, the best insulation ranking has been obtained from the weights assigned to the parameters in the objective function, using the technique of the genetic algorithm (GA) applied to multi-criteria selection. The optimization results showed that polyurethane (PU) insulation, applied with a thickness of 1 cm was the best option for the roof, considering the building functional parameters, occupant metabolic activity, clothing insulation and climate conditions. On the other hand, when the Brazilian standard was utilized, rock wool (2 cm) was considered the best choice.

Moisture risk assessment of cross-laminated timber walls: Perspectives on climate conditions and water vapor resistance performance of building materials

Cross-laminated timber (CLT), an engineering wood material prepared by bonding lamina in a vertical direction, is actively used in roofs, floors and shear walls of residential and commercial buildings, owing to its excellent structural stability, insulation performance, among other advantages. The building envelope, to which the wood-based material is applied, should be designed to prevent moisture problems. In this study, the ply-lam CLT with plywood was prepared, and its hygrothermal properties including the thermal conductivity, water vapor resistance factor, specific heat capacity, bulk density, and porosity were analyzed. A small-scale test demonstrates the feasibility of hygrothermal behavior evaluation of the wall with ply-lam CLT by numerical simulation. Moreover, the moisture risk of the ply-lam CLT house walls was evaluated by analyzing the climate conditions of 20 major cities in Korea. The moisture risk assessment results imply, that to ensure water stability, the envelope should be designed considering the type of insulation material, its hygrothermal properties, thickness, climate conditions of the area, etc.

Study on the mechanical property of precast reinforced concrete sandwich insulation walls

In this paper, a finite element analysis model of a precast reinforced concrete sandwich insulation wall (PRCSIW) is established according to the out-of-plane static load test of the wall. With the consideration of the structural characteristics of PRCSIW, the influences of insulation layer thickness, insulation material type, fastening piece type and fastening piece distribution mode on the mechanical performance of the wall is analyzed. Our work gives a theoretical basis for the optimal design of precast sandwich insulation walls.