A Realistic Approach for Testing the Thermal Insulation Value of Closed-Cell Spray Polyurethane Foam Roof Insulation

2008 ◽  
pp. 55-55-8
Author(s):  
M Sherman ◽  
W Mullally ◽  
J Garcia ◽  
D Dobrez-Flores
Keyword(s):  
Polyurethane Foam ◽  
Thermal Insulation ◽  
Realistic Approach ◽  
Closed Cell ◽  
Thermal Insulation Value ◽  
Insulation Value

A comparison of methods for assessing the thermal insulation value of children’s schoolwear in Kuwait

2012 ◽  
Vol 43 (1) ◽  
pp. 203-210 ◽  
Author(s):  
Khaled Al-Rashidi ◽  
Dennis loveday ◽  
Nawaf Al-Mutawa ◽  
George Havenith
Keyword(s):  
Thermal Insulation ◽  
Comparison Of Methods ◽  
Thermal Insulation Value ◽  
Insulation Value

scholarly journals Artificial Neural Network Estimation of Thermal Insulation Value of Children’s School Wear in Kuwait Classroom

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Khaled Al-Rashidi ◽  
Radhi Alazmi ◽  
Mubarak Alazmi
Keyword(s):  
Neural Network ◽  
Artificial Neural Network ◽  
Surface Area ◽  
Body Surface Area ◽  
Thermal Insulation ◽  
Body Surface ◽  
The Body ◽  
Artificial Neural ◽  
Thermal Insulation Value ◽  
Insulation Value

Artificial neural network (ANN) was utilized to predict the thermal insulation values of children’s school wear in Kuwait. The input thermal insulation data of the different children’s school wear used in Kuwait classrooms were obtained from study using thermal manikins. The lowest mean squared error (MSE) value for the validation data was 1.5 × 10−5 using one hidden layer of six neurons and one output layer. The R2 values for the training, validation, and testing data were almost equal to 1. The values from ANN prediction were compared with McCullough’s equation and the standard tables’ methods. Results suggested that the ANN is able to give more accurate prediction of the clothing thermal insulation values than the regression equation and the standard tables methods. The effect of the different input variables on the thermal insulation value was examined using Garson algorithm and sensitivity analysis and it was found that the cloths weight, the body surface area nude (BSA0), and body surface area covered by one layer of clothing (BSAC1) have the highest effect on the thermal insulation value with about 29%, 27%, and 23%, respectively.

Temperature dependency of the long-term thermal conductivity of spray polyurethane foam

2021 ◽  
pp. 174425912110454
Author(s):  
Neal Holcroft
Keyword(s):  
Thermal Conductivity ◽  
Polyurethane Foam ◽  
Cellular Structure ◽  
Gas Diffusion ◽  
Temperature Dependent ◽  
Blowing Agent ◽  
Closed Cell ◽  
Wall Assembly ◽  
Cell Foam

The thermal properties of closed-cell foam insulation display a more complex behaviour than other construction materials due to the properties of the blowing agent captured in their cellular structure. Over time, blowing agent diffuses out from and air into the cellular structure resulting in an increase in thermal conductivity, a process that is temperature dependent. Some blowing agents also condense at temperatures within the in-service range of the insulation, resulting in non-linear temperature dependent relationships. Moreover, diffusion of moisture into the cellular structure increases thermal conductivity. Standards exist to quantify the effect of gas diffusion on thermal conductivity, however only at standard laboratory conditions. In this paper a new test procedure is described that includes calculation methods to determine Temperature Dependent Long-Term Thermal Conductivity (LTTC(T)) functions for closed-cell foam insulation using as a test material, a Medium-Density Spray Polyurethane Foam (MDSPF). Tests results are provided to show the validity of the method and to investigate the effects of both conditioning and mean test temperature on change in thermal conductivity. In addition, testing was conducted to produce a moisture dependent thermal conductivity function. The resulting functions were used in hygrothermal simulations to assess the effect of foam aging, in-service temperature and moisture content on the performance of a typical wall assembly incorporating MDSPF located in four Canadian climate zones. Results show that after 1 year, mean thermal conductivity increased 15%–16% and after 5 years 23%–24%, depending on climate zone. Furthermore, the use of the LTTC(T) function to calculate the wall assembly U-value improved accuracy between 3% and 5%.

Multi-scale simulation study on the hygrothermal behavior of closed-cell thermal insulation

Energy ◽  
2020 ◽  
Vol 196 ◽  
pp. 117142
Author(s):  
Shanshan Cai ◽  
Haijin Guo ◽  
Boxiong Zhang ◽  
Guowen Xu ◽  
Kun Li ◽  
...  
Keyword(s):  
Thermal Insulation ◽  
Simulation Study ◽  
Multi Scale ◽  
Hygrothermal Behavior ◽  
Closed Cell

scholarly journals Waste Utilization: Insulation Panel from Recycled Polyurethane Particles and Wheat Husks

Materials ◽  
2019 ◽  
Vol 12 (19) ◽  
pp. 3075
Author(s):  
Štěpán Hýsek ◽  
Pavel Neuberger ◽  
Adam Sikora ◽  
Ondřej Schönfelder ◽  
Gianluca Ditommaso
Keyword(s):  
Thermal Conductivity ◽  
Winter Wheat ◽  
Polyurethane Foam ◽  
Thermal Insulation ◽  
Waste Utilization ◽  
Waste Materials ◽  
Uptake Coefficient ◽  
Coefficient Of Thermal Conductivity ◽  
Nominal Density ◽  
Wheat Husk

This study provides a solution for the utilization of two waste materials, namely the residues of soft polyurethane foam from the production of mattresses and winter wheat husks. Thermal insulation panels with a nominal density of 50–150 kg/m3, bonded one-component moisture curing polyurethane adhesive, were developed, and the effect of the ratio between recycled polyurethane foam and winter wheat husk on internal bond strength, compressive stress at 10% strain, water uptake, coefficient of thermal conductivity, and volumetric heat capacity was observed. The developed composite materials make use of the very good thermal insulation properties of the two input waste materials, and the coefficient of thermal conductivity of the resulting boards achieves excellent values, namely 0.0418–0.0574 W/(m.K). The developed boards can be used as thermal insulation in the structures of environmentally friendly buildings.

Research on Impact Factors of Thermal Insulation Material Based on Grey Relational Analysis

2011 ◽  
Vol 328-330 ◽  
pp. 1377-1380 ◽  
Author(s):  
Xiao Gang Zhao ◽  
Yi Zhou ◽  
Shi Xiang Pan
Keyword(s):  
Polyurethane Foam ◽  
Thermal Insulation ◽  
Field Experiments ◽  
Impact Factors ◽  
Insulation Material ◽  
Rigid Polyurethane Foam ◽  
Relational Analysis ◽  
Grey Relational ◽  
Insulation Quality

According to application of thermal insulation materials in the practical construction of electrical heat tracing in viscous oil pipeline, impact factors of rigid polyurethane foam widely used as new insulation material are systemically analyzed by Grey Relational Analysis (GRA) in the theory of Grey System to find out priorities among those factors. To further study their performances and to improve the quality of constructions, ten field experiments were carried out in Tanggula Mountain. The foaming conditions and the performances of the rigid polyurethane foam were recorded to be analyzed by GRA. The analysis results, acting as scientific guidance for construction, show that the insulation quality of rigid polyurethane foam is mainly determined by the ratio of components, thus the priority is to control such dominant factor and overall consideration of other factors should be taken to ensure insulation quality in the foaming process. More field experiments prove that the ratio should be controlled between 1.15 and 1.18 to ensure the thermal insulation.

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