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The walls are made of 25 cm thick bricks without insulation except for the cellar. The windows and glassdoors are standard double glazed with an intermediate layer of air We have used EnergyPlus for simulating the house model. For building our simulation framework we have used the software tool Building Controls Virtual Test Bed (BCVTB).
In order to calculate heat flow, it is first necessary to calculate the thermal resistance ("R-value") for each layer of insulation. For pipe insulation, the R-value varies not only with the insulation thickness and thermal conductivity ("k-value") but also with the pipe outer diameter and the average material temperature.
To calculate thermal transmittance when there are "bridging" mortar joints it is necessary to calculate two quantities, known as R max and R min. R max can be thought of as the total thermal insulance obtained if it is assumed that there is no lateral flow of heat and R min can be thought of as the total thermal insulance obtained if it is ...
This is a list of insulation materials used around the world. Typical R-values are given for various materials and structures as approximations based on the average of available figures and are sorted by lowest value. R-value at 1 m gives R-values normalised to a 1 metre (3 ft 3 in) thickness and sorts by median value of the range.
Loose-fill insulation comes in loose fibers or pellets and should be blown into a space. Rigid foam is more expensive than fiber, but generally has a higher R-value per unit of thickness. Foam-in-place insulation can be blown into small areas to control air leaks, like those around windows, or can be used to insulate an entire house. [33]
Thermal insulation is the reduction of heat transfer (i.e., the transfer of thermal energy between objects of differing temperature) between objects in thermal contact or in range of radiative influence. Thermal insulation can be achieved with specially engineered methods or processes, as well as with suitable object shapes and materials.
While in 1976 there were roughly 100 cellulose insulation firms with 125 plants in the US, by 1978 there were more than 350 firms with more than 500 plants 1. Cellulose insulation was produced locally by small manufacturers who purchased ready-to-operate machines and offered a cheap and easy low-tech production process.
The fouling resistances can be calculated for a specific heat exchanger if the average thickness and thermal conductivity of the fouling are known. The product of the average thickness and thermal conductivity will result in the fouling resistance on a specific side of the heat exchanger. [17]