Search Results (3)

The main purpose of this paper is to present the use of super thermal insulation materials for a historical building through a calculation-based case study. The development of the insulation materials is based on the objective of making buildings as energy efficient as possible, and the energy loss should be kept to a minimum, for both new and existing buildings. For this purpose, the thermal insulation materials used so far have not always achieved maximum effectiveness. In the case of historical buildings, it is particularly difficult to solve insulation issues, as the building cannot lose its former appearance. However, aerogel and vacuum insulation panels can also be used as thin thermal protective layers. In this paper, we will specifically deal with the presentation of the possible application of super thermal insulation materials, such as vacuum insulation panels and aerogels. We will present thermal conductivity measurement results as well as their application through building energetic calculations applied to a historical building as a case study. We will also present certain calculations regarding the costs. The paper highlights that savings of energy costs of approximately 30% can be reached using vacuum insulation sandwich panels. Furthermore, the overall thermal transmittance of the building also decreases by about 35% if vacuum insulation sandwich panels are used for the refurbishment. Full article

Nowadays, the usage of thermal insulation materials is widespread not only in the building sector but also in the vehicle industry. The application of fibrous or loose-fill insulation materials like glass wool or mineral wool as well as aerogel is well known. Aerogel-based materials are among the best solid materials for thermal insulation available today; they are prepared through a sol–gel process. For building walls, the glass-fiber-enhanced types are the frequently used ones. They are prepared by adding the liquid–solid solution to the fibrous batting, which is called a sol–gel process. In the present paper, the changes in the most important building physical properties of aerogel blankets after thermal annealing are presented. The samples were subjected to isochronal heat treatments from 70 to 210 °C for 24 h. The changes in the thermal conductivity were followed by Holometrix Lambda heat flow meter, and differential scanning calorimetry results were also recorded. From the measured values, together with the densities, the most important thermal properties were calculated, such as thermal resistance, diffusivity, effusivity (heat absorption), and thermal inertia. In this paper, we attempt to clarify the role played by thermal annealing in the transient thermal properties of aerogel materials. Besides presenting the measurement results, a theoretical background is given. The investigations of not only the steady-state but also the transient thermal parameters of the materials are momentous at the design stage. Full article

Nowadays, besides the use of conventional insulations (plastic foams and wool materials), aerogels are one of the most promising thermal insulation materials. As one of the lightest solid materials available today, aerogels are manufactured through the combination of a polymer with a solvent, forming a gel. For buildings, the fiber-reinforced types are mainly used. In this paper, the changes both in the thermal performance and the material structure of the aerogel blanket are followed after thermal annealing. The samples are put under isothermal heat treatments at 70 °C for weeks, as well as at higher temperatures (up to 210 °C) for one day. The changes in the sorption properties that result from the annealing are presented. Furthermore, the changes in the thermal conductivity are followed by a Holometrix Lambda heat flow meter. The changes in the structure and surface of the material due to the heat treatment are investigated by X-ray diffraction and with scanning electron microscopy. Besides, the above-mentioned measurement results of differential scanning calorimetry experiments are also presented. As a result of using equipment from different laboratories that support each other, we found that the samples go through structural changes after undergoing thermal annealing. We manifested that the aerogel granules separate down from the glass fibers and grow up. This phenomenon might be responsible for the change in the thermal conductivity of the samples. Full article