The Effect of Lightweight Concrete Cores on the Thermal Performance of Vacuum Insulation Panels

Abstract

The performance of vacuum insulation panels (VIPs) is strongly affected by several factors, such as panel thickness, design, quality of vacuum, and material type. In particular, the core materials inside VIPs significantly influence their overall performance. Despite their superior insulation performance, VIPs are limited in their widespread use as structural materials, because of their low material strength and the relatively expensive core materials. As an alternative core material that can compensate these limitations, foamed concrete, a type of lightweight concrete with very low density, can be used. In this study, two different types of foamed concrete were used as VIP core materials, with their effects on the thermal behavior of the VIPs having been evaluated using experimental and numerical methods. To confirm and generate numerical models for VIP analysis, micro-computed tomography (micro-CT) was utilized. The obtained results show that insulation effects increase effectively when panels with lightweight concrete are in a vacuum, and both foamed concrete types can be effectively used as VIP core materials.

Experimental and Numerical Verification of the Railway Track Substructure with Innovative Thermal Insulation Materials

“…The used of waste materials as components of foamed concrete mixture (common as replacement aggregate or cement, and as fiber) was analyzed by other scientists. Dhir et al [ 59 ], Chung Y-S. et al [ 70 ], Kadela et al [ 71 ], and Rommel et al [ 72 ] used fly ash as a cement replacement, while Lesovik et al [ 73 ] used a composition of Portland cement, opoka marl, and fly ash as a composite binder. Wongkvanklom et al [ 74 ] investigated the impact of foam content on mechanical, thermal, and sound properties of foamed concrete made with 15 M NaOH solution, sodium silicate/NaOH ratio (NS/NaOH) of 1.00, sand/ash ratio of 1.25, liquid/fly ash ratio of 0.4.…”

“…Moreover, in recent years, FC has been used extensively in various areas of construction around the world, such as in Germany, Great Britain, USA, Canada, and Brazil [ 81 , 82 , 83 ]. Due good mechanical and thermal properties, foamed concrete is used in various type of panel [ 70 , 84 ]. In addition, foamed concrete was used by Kadela et al [ 85 , 86 ], Drusa et al [ 87 , 88 ], Tian et al [ 35 ], and Lee at al.…”

Comparative life cycle assessment of different vacuum insulation panel core materials using a cradle to gate approach

“…Alam and Singh (2019) proposed the use of sawdust powder in combination with fumed silica in the VIP core for ecofriendly VIPs. The use of lightweight concrete have also been proposed to improve material strength and the overall cost of the VIP core material (Chung et al, 2020). Thermal conductivities in the region of 0.049-0.1086 W/(m.K) were achieved, indicating that concrete may not be suitable for use in buildings needing a high level of insulation.…”

The bias of the interface thickness and diffusivity of concrete comprising Platonic aggregates induced by areal analysis

“…For certain given packing states of particles, such as maximally random jammed packings [12] and random close packings [13], various correlation functions are usually used to characterize the structure of the packing systems [14]. In addition, the microstructures of discrete particles imbedded in some matrix are observed by 1D (lineal) and 2D (areal) analyses, then inferences are drawn therefrom as to the actual 3D structure [15][16][17][18]. Guo et al [19] reconstructed the 3D percolating filamentary ferrite phase from 2D micrographs on austenitic-ferritic cast duplex stainless steels.…”