Non-Steady-State Behavior of Thermal Insulations

Analysis of Transient Measurements Obtained for Thermal Insulations with the ORNL Flat Tester

“…Finite difference calculations [6] were also used to obtain values for the adjustable parameter, specific heat, and the results agree with the two region analysis and thus confirm the reasonableness of replacing the actual volumetric heat generation with a step-change in heat flux on the screen bound- ary. The average numerically determined specific heat for the Fiberglass Transfer Standard is about 30% greater than previously reported for fiberglass [7], and the average specific heat determined for the SRM 1450b is about 12 % greater than a value calculated from the composition of the material [4]. Table 4 contains results obtained for six measurements with SRM 1450b and six measurements with fiberglass transfer standard.…”

“…The apparatus, identified as the ORNL screen tester, was built as part of the Materials Research subtask in the U.S. Department of Energy sponsored program, &dquo;Building Thermal Envelope Systems and Materials.&dquo; Descriptions of the apparatus and procedure and experimental results have been reported [1][2][3][4]. ** The present paper will be limited to a brief review of the equipment and a discussion of its use to obtain transient thermal data.…”

A Procedure for Determining the Thermal Diffusivity of Materials

“…The ASTM book of Standards [I] indicates that thermal diffusivity can be obtained by measuring thermal conductivity, density and mass specific heat separately, but no procedure is given for determining thermal diffusivity directly. McElroy, Graves, Yarbrough and Tong [2] have presented a ~rocedure for determining thermal diffusivity using an apparatus that was developed originally to measure thermal conductivity. Their procedure requires a rather lengthy analysis of test results, and represents the test condition by a slightly simplified model.…”

A New Method for Numerical Modeling of Heat Transfer in Thermal Insulations Products

“…al. (1985-1986), and McElroy (1986. Lee (1986Lee ( , 1988Lee ( , and 1989 and 2000) proposed radiation models which rigorously account for fiber morphology and orientation.…”