CHARACTERIZATION OF AEROGEL BASED THERMAL INSULATION BLANKETS, ECONOMICS, AND APPLICATIONS FOR DOMESTIC WATER HEATERS

Abstract

One of the main ways to improve the performance of thermal systems is using better thermal insulation. Recent developments of high performance thermal insulation introduced thermal insulation blankets for low and moderately high temperature applications. One of the leading insulation technologies are aerogel based insulation blankets. Before studying the performance of thermal systems insulated with these materials, it is important to characterize these blankets under conditions similar to the operating conditions. In this study, thermal conductivity measurement experiments are conducted on Low Temperature High Performance Insulation (LTHPI) and High Temperature High Performance Insulation (HTHPI) blankets and their results were discussed. Tests also conducted are scanning-electron-microscope (SEM) imaging to better understand the nano-structure and thermal conductivity test. Results in this paper show SEM images for Aspen®’s Spaceloft® and Pyrogel® XT-E blankets, and X-ray imaging showing the components inside the blankets’ aerogel to be Silicon, Oxygen, and Carbon. Thermal conductivity measurements were conducted for both LTHPI and LTHPI insulation materials. The thermal conductivity results confirm the results mentioned in the literature, showing that the thermal conductivity is 0.0159 W / (m.K) for LTHPI and 0.0188 W / (m.K) for HTHPI at 25 oC. It can be said that the tested blankets show a promising performance in thermal systems. This paper also demonstrates a comparison of utilizing high performance thermal insulation with current industry practice in domestic water heaters, and a discussion on its economic impacts for individual and national levels. This discussion shows that a minimum of 3.7 billion USA dollars can be saved annually by adjusting regulations to enforce water heater manufacturers to use HPI in their products.

Keywords

• Thermal Conductivity
• Aerogel Thermal Insulation Blankets
• Domestic Water Heaters
• Economics of Aerogel Insulation
• Aerogel Blankets Characterization
• Scanning-Electron-Microscopy of Aerogel Blankets

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