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

Year 2020, , 403 - 419, 01.12.2020

Emadeddin Tanbour

https://doi.org/10.18186/thermal.834034

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

References

• [1] US Department of Energy, Final Rule, Energy and Water Conservation Standards and Their Compliance Dates. Energy Conservation Program for Consumer Products. US Department of Energy,2016.
• [2] Lutz, J., Grant, P., Kloss, M. Simulation Models for Improved Water Heating Systems, Lawrence Berkeley National Laboratory. Berkeley, CA, USA, 2013.
• [3] Sedeh, M. M., Khodadadi, J. M. Energy Efficiency Improvement and Fuel Savings in Water Heaters Using Baffles. Applied Energy, 102, 520-533, 2013.
• [4] Emad Y. Tanbour and Ramin K. Rahmani, “Enhancement of Temperature Blending in Convective Heat Transfer by Motionless Inserts with Variable Segment Length ,” Proceedings of IMECE 2009, 2009 ASME International Mechanical Engineering and Exposition, November 13-19, 2009, Lake Buena Vista, Florida, USA
• [5] Emad Y. Tanbour and Ramin K. Rahmani, “A Numerical Study of The Thermal Performance of Two Stationary Insert Design in Internal Compressible Flow,” Proceedings of 2009 ASME Summer Heat Transfer Conference, HT2009, July 19-23, 2009, San Francisco, Ca, USA
• [6] Emad Y. Tanbour and Ramin K. Rahmani, “Enhancement Of Natural Convection Heat Transfer Rate In Internal Compressible Flows By Inserting Stationary Inserts,” Proceedings of 2008 ASME Summer Heat Transfer Conference, HT2008, August 10-14, 2008, Jacksonville, Florida USA
• [7] Emad Y. Tanbour and Ramin K. Rahmani, “Experimental Study of Convective Heat Transfer in A Vertical Pipe with Stationary Inserts,” Proceedings of 2008 ASME Summer Heat Transfer Conference, HT2008, August 10-14, 2008, Jacksonville, Florida USA
• [8] Ramin K. Rahmani, Anahita Ayasoufi, Emad Y. Tanbour and Hosein Molavi, “Enhancement of Temperature Blending in Convective Heat Transfer by Motionless Inserts With Variable Segment Length” Journal of Thermal Science and Engineering Applications, September 2010, Vol. 2
• [9] Ramin K. Rahmani, Emad Y. Tanbour, Anahita Ayasoufi and Hosein Molavi, “Enhancement of Convective Heat Transfer in Internal Compressible Flows by Stationary Inserts” Journal of Thermal Science and Engineering Applications, 2010, Vol. 2
• [10] Tajwar, S., Saleemi, A. R., Ramzan, N., Naveed, S. Improving Thermal and Combustion Efficiency of Gas Water Heater. Applied Thermal Engineering, 31, 1305-1312, 2011.
• [11] Ibrahim, O., Fardoun, F., Younes, R., Louahlia-Gualous, H. Review Of Water Heating Systems: General Selection Approach Based on Energy and Environmental Aspects. Building and Environment, 72, 259-286, 2014.
• [12] He, Y.-L., Xie, T. Advances of Thermal Conductivity Models of Nanoscale Silica Aerogel Insulation Materials. Applied Thermal Engineering, 81, 28-50. 2015.
• [13] Hrubesh, L. W. Aerogel Applications. Journal of Non-crystalline Materials, 225, 335-342, 1998.
• [14] Cohen, E. Thermal Properties of Advanced Aerogel Insulation, Massachusetts Institute of Technology, Department of Mechanical Engineering, Boston, MA, USA, 2011.
• [15] Zou, Y. Preparation of Silica Aerogels with Improved Mechanical Properties and Extremely low Thermal Conductivities through Modified Sol-Gel Process. Massachusetts Institute of Technology. Boston, MA, USA, 2010.
• [16] Goutierre, T. Advanced Thermal Insulation for Energy Efficient Buildings: Structural Performance of Aerogel Composite Panels. Massachusetts Institute of Technology. Boston, MA, USA, 2011.
• [17] Cuce, E., Cuce, P. M., Wood, C. J., Riffat, S. B. Toward Aerogel Based Thermal Superinsulation In Buildings: A Comprehensive Review. Renewable and Sustainable Energy Reviews, 34, 273-299, 2014.
• [18] Bardy, E. R., Mollendorf, J. C., Pendergast, D. R. Thermal Conductivity and Compressive Strain of Aerogel Insulation Blankets under Applied Hydrostatic Pressure. Journal of Heat Transfer, 129, 232-235, 2007.
• [19] Oh, K. W., Kim, D. K., Kim, S. H. Ultra-porous Flexible PET/Aerogel Blanket for Sound Absorption and Thermal Insulation. Fibers and Polymers, 10(5), 731-737, 2009.
• [20] Coffman, B. E., Fesmire, J. E., White, S., Gould, G., Augustynowicz, S. Aerogel Blanket Insulation Materials for Cryogenic Applications. Transactions of the Cryogenic Engineering Conference-CEC, Tucson, Arizona, USA, 913-920, 2009.
• [21] Wei, G., Liu, Y., Zhang, X., Yu, F., Du, X. Thermal Conductivities Study on Silica Aerogel and its Composite Insulation Materials. International Journal of Heat and Mass Transfer, 54, 2355-2366, 2011.
• [22] Gould, G. L., Lee, J. K., Stepanian, C. J., Lee, K. P. High Strength, Nanoporous Bodies Reinforced With Fibrous Materials, US Patent No. 7,560,062. US Patent Office, Washington, DC, USA,2009.
• [23] Stepanian, C. J., Gould, G. L., & Begag, R. USA Patent No. 12/365,234. US Patent Office, Washington, DC, USA,2009.
• [24] Tang, Y., Polli, A., Bilgrien, C. J., Young, D. R., Rhine, W. E., & Gould, G. L. USA Patent No. 11/761,924. US Patent Office, Washington, DC, USA,2007.
• [25] Aspen Aerogels Inc. Pyrogel XT-E material safety data sheet. Northborough, MA, USA,2015.
• [26] Aspen Aerogels Inc. Spaceloft material safety data sheet. Northborough, MA, USA,2015.
• [27] Central Michigan University. Hitachi 3400N-II Scanning Electron Microscope. Retrieved April 6, 2018 from https://www.cmich.edu/colleges/cst/biology/microscopy/Pages/SEM.aspx
• [28] ASTM International. Standard C518: Standard Test Method for Steady-State Thermal Transmission Properties by Means of the Heat Flow Meter Apparatus. www.astm.org
• [29] Omega Engineering Inc. Super OMEGACLAD XL Thermocouples Probes: A Technical Advance in Temperature Measurements. Omega Engineering Inc. Stamford, CT, USA,2016.
• [30] International Thermal Instruments Company Inc. Heat Flux Transducers Product Information Package. International Thermal Instruments Company Inc. Del Mar, CA, USA,2016.
• [31] National Instruments, NI USB-9213 User Guide and Specifications. National Instruments. Austin, TX, USA
• [32] The Statistic Portal. Number of Households in the U.S. from 1960 to 2015 (in millions). Retrieved from Statista, The Statistic Portal:http://www.statista.com/statistics/183635/number-of-households-in-the-us/ ,2016.
• [33] N. Alpay KÜREKCİ , Optimum Insulation Thickness For Cold Storage Walls: Case Study For Turkey, Journal of Thermal Engineering, Research Article, Vol. 6, No. 5, pp. 873-887, October, 2020.