Thermal Characteristics of Gas-Filled Fiber Powder Insulation Systems
This investigation was initiated to study gas-filled fiber-powder insulations. It has been experimentally shown that these systems may exhibit a thermal conductivity as low as one-half that of air. Selected gas-filled, fiber-powder systems were measured and the important role that powder particle size plays was demonstrated. The powders which were investigated included carbon black, perlite, flame-prepared silica, and silica-carbon black mixtures.
The existing theoretical model of Luikov, Shashkov, Vasiliev, and Fraiman was used for gas-filled powders and extended to the case of gas-filled, fiber-powder systems by adding Bankvall’s theoretical model for fibrous materials. These models are useful in evaluating candidate powders and gases and they can be used to establish conductivity limits of gas-filled powder systems.
KeywordsThermal Conductivity Carbon Black Fumed Silica Silica Aerogel Powder System
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- 1.D. B. Rogers, Investigation of the Effective Thermal Conductivity of Gas-Filled Fiber-Powder Insulation Systems for Residential and Commercial Structures, Ph.D. Dissertation, Vanderbilt University, Mechanical Engineering Department, 1975.Google Scholar
- 5.J. D. Verschoor and P. G. Greebler, Heat Transfer by Gas Conduction and Radiation in Fibrous Insulations, Transactions of the ASME, August, 1952, pp 961–968.Google Scholar
- 7.C. L. Johnson and D. J. Hollweger, Some Heat Transfer Considerations in Nonevacuated Cryogenic Powder Insulation, Advances in Cryogenic Engineering, Vol. 2, 1966, pp 77–88.Google Scholar
- 8.C. M. Pelanne, Experiments on the Separation Heat Transfer Mechanisms in Low-Density Fibrous Insulation, 8th Conference on Thermal Conductivity, Thermal Conductivity Proceedings, Edited by C. Y. Ho and R. E. Taylor, Plenum Press, 1969, pp 897–911.Google Scholar