Transparent Vacuum Insulation Panels

New, low-cost transparent vacuum insulation panels (TVIPs) using structured cores for the windows of existing buildings are proposed. The TVIP is produced by inserting the structured core, the low-emissivity film, and the adsorbent into the transparent gas barrier envelopes. In this chapter, the authors introduce the outlines, the design and thermal analysis method, the performance evaluation (test) method. Firstly, five spacers, namely peek, modified peek, mesh, silica aerogel, and frame, are selected as the structured core. The effective thermal conductivity of TVIPs with five different spacers is evaluated at different pressure levels by applying numerical calculation. The result indicated that TVIPs with frame and mesh spacers accomplish better insulation performance, with a center-of-panel apparent thermal conductivity of 7.0 × 10−3 W/m K at a pressure of 1 Pa. The apparent thermal conductivity is the same as the value obtained by the simultaneous evacuation thermal conductivity measurement applying the heat flux meter method. Furthermore, using a frame-type TVIP with a total thickness of 3 mm attached to an existing window as a curtain decreases the space heat loss by approximately 69.5%, whereas the light transparency decreases to 75%.

Thermal Performance of LSF Wall Systems with Vacuum Insulation Panels

Lightweight Steel Frames (LSF) in building construction are becoming more popular due to their fast, clean, and flexible constructability. Typical LSF wall panels are made of cold-formed and thin-walled steel lipped channel studs with plasterboard linings. Due to the high thermal conductivity of steel, these LSF components must be well engineered and covered against unintended thermal bridges. Therefore, it is essential to investigate the heat transfer of the LSF wall of different configurations and reduce heat loss through walls by lowering the thermal transmittance, which would ultimately minimise the energy consumption in buildings. The effect of novel thermal insulation material, Vacuum Insulation Panels (VIP), their position on the LSF wall configuration, and Oriented Strand Board (OSB) and plasterboard’s effect on the thermal transmittance of LSF walls were investigated through numerical analysis. A total of 56 wall configurations and 112 finite element models were analysed and compared with the minimum U-value requirements of UK building regulations. Numerical model results exhibited that using plasterboards instead of OSB has no considerable effect on the U-value of the LSF walls. However, 77% (4 times) of U-value reduction was exhibited by introducing the 20 mm VIP. Moreover, the position of the VIP to the U-value of LSF was negligible. Based on the results, optimum LSF wall configurations were proposed by highlighting the construction methods. Additionally, this study, through literature, seeks to identify other areas in which additional research can be conducted to achieve the desired thermal efficiency of buildings using LSF wall systems.

Analytical Study of Insulation Characteristics of Thermal Batteries with Vacuum Insulation

In this study, a thermal battery is designed with vacuum insulation to improve its thermal insulation. Thermal insulation is one of the many factors that determine the stability and operation of the battery. The battery’s operating time as well as the improvement in its thermal insulation performance were analyzed. The location of the vacuum insulation was set as a variable in the analysis models. The thermal battery was subjected to unsteady heat transfer analysis until the electrolyte temperature reached 450°C. Vacuum insulation was applied to the part of the base thermal battery to fabricate three model batteries. Compared with the base model B, the operating time increased by 48% for the model BS, 76% for the model BSB, and 179% for the model BSBT. Due to the large area of the side, a large amount of heat was transferred; the quantity of heat transfer was in the order B>BS>BSB>BSBT. In the model BSBT, the heat loss per unit area was reduced by 93% at the side, top, bottom compared with the base model. The results of this study will serve as basic data for the design of thermal batteries with vacuum insulation and for improvement in insulation performance.

Super Insulation Materials—An Application to Historical Buildings

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.

Heat and Moisture Modelling of Vacuum Insulated Retrofits with Experimental Validation

Vacuum insulation panels (VIPs) offer 8-10 times the thermal resistance of fiberglass insulation and would fit the need for a low conductivity exterior insulation. A composite insulation panel using VIPs encased in rigid foam was developed, built, and tested. Two different sizes of VIPs were used for that stage of the project, and after monitoring and evaluation, they showed contrasting results. A simulation study was performed to find the optimal VIP solution that maximized the effective thermal conductivity and minimized the mould growth potential. In total, 5 wall assemblies with VIPs used as the exterior insulation were simulated using WUFI and WUFI2D. The simulations showed that the humidity levels at the inside face of the OSB inboard of the VIPs decreased when 200 mm by 300 mm VIPs were used, but they did not reach the thermal performance thresholds of R5.28 m2K/W. The hygrothermal analysis showed that under similar conditions, a VIP insulated wall assembly would have a lower relative humidity at the sheathing surface compared to EPS and XPS. The one-and two-dimensional simulations were compared and found that WUFI Pro was capable to evaluate a VIP-insulated wall assembly.