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Title: Computation of total hemispherical emissivity from directional spectral models

Authors:
; ; ; ;
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1417100
Grant/Contract Number:
NE0000743
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
International Journal of Heat and Mass Transfer
Additional Journal Information:
Journal Volume: 109; Journal Issue: C; Related Information: CHORUS Timestamp: 2018-01-16 12:41:19; Journal ID: ISSN 0017-9310
Publisher:
Elsevier
Country of Publication:
United Kingdom
Language:
English

Citation Formats

King, Jonathan L., Jo, Hangjin, Loyalka, Sudarshan K., Tompson, Robert V., and Sridharan, Kumar. Computation of total hemispherical emissivity from directional spectral models. United Kingdom: N. p., 2017. Web. doi:10.1016/j.ijheatmasstransfer.2017.01.120.
King, Jonathan L., Jo, Hangjin, Loyalka, Sudarshan K., Tompson, Robert V., & Sridharan, Kumar. Computation of total hemispherical emissivity from directional spectral models. United Kingdom. doi:10.1016/j.ijheatmasstransfer.2017.01.120.
King, Jonathan L., Jo, Hangjin, Loyalka, Sudarshan K., Tompson, Robert V., and Sridharan, Kumar. Thu . "Computation of total hemispherical emissivity from directional spectral models". United Kingdom. doi:10.1016/j.ijheatmasstransfer.2017.01.120.
@article{osti_1417100,
title = {Computation of total hemispherical emissivity from directional spectral models},
author = {King, Jonathan L. and Jo, Hangjin and Loyalka, Sudarshan K. and Tompson, Robert V. and Sridharan, Kumar},
abstractNote = {},
doi = {10.1016/j.ijheatmasstransfer.2017.01.120},
journal = {International Journal of Heat and Mass Transfer},
number = C,
volume = 109,
place = {United Kingdom},
year = {Thu Jun 01 00:00:00 EDT 2017},
month = {Thu Jun 01 00:00:00 EDT 2017}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1016/j.ijheatmasstransfer.2017.01.120

Citation Metrics:
Cited by: 2works
Citation information provided by
Web of Science

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  • The specific heat c and total hemispherical emissivity {var_epsilon}{sub h} of iron and constantan have been measured using a simultaneous-measurement method proposed in a previous paper to verify the accuracy of the measurements. Cylindrical specimens, whose geometrical shape is presumed to be more appropriate than those in the previous study are used as the compound specimens necessary for the method. To obtain more accurate results, an expression for the temperature versus time curve has been developed; this expression is highly accurate over the entire temperature range. For iron, the measured c- and {var_epsilon}{sub h}-values are compared with c-values recommended inmore » the CINDAS Data Series and with {var_epsilon}{sub h}-values previously measured by H. Masuda and M. Higano, respectively. For constantan, empirical relations between c and T (temperature) and {var_epsilon}{sub h} and T are obtained. Errors in the present results are analyzed and the total errors in the results are estimated.« less
  • High-temperature high-vacuum electrostatic levitation (HTHVESL) and differential scanning calorimetry (DSC) were combined to determine the hemispherical total emissivity {epsilon}{sub {ital T}}, and the specific heat capacity {ital c}{sub {ital p}}, of the undercooled liquid and throughout the glass transition of the Zr{sub 41.2}Ti{sub 13.8}Cu{sub 12.5}Ni{sub 10.0}Be{sub 22.5} bulk metallic glass forming alloy. The ratio of {ital c}{sub {ital p}}/{epsilon}{sub {ital T}} as a function of undercooling was determining from radiative cooling curves measured in the HTHVESL. Using specific heat capacity data obtained by DSC investigations close to the glass transition and above the melting point, {epsilon}{sub {ital T}} and {italmore » c}{sub {ital p}} were separated and the specific heat capacity of the whole undercooled liquid region was determined. Furthermore, the hemispherical total emissivity of the liquid was found to be about 0.22 at 980 K. On undercooling the liquid, the emissivity decreases to approximately 0.18 at about 670 K, where the undercooled liquid starts to freeze to a glass. No significant changes of the emissivity are observed as the alloy undergoes the glass transition. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.« less
  • Radiative cooling curves of nickel, zirconium, and silicon melts that were obtained using the high-temperature, high-vacuum electrostatic levitator (HTHVESL) have been analyzed to determine the ratio between the constant-pressure specific heat and the hemispherical total emissivity, c{sub p}(T)/{var_epsilon}{sub T}(T). This ratio determined over a wide liquid temperature range for each material allows one to determine c{sub p}(T) if {var_epsilon}{sub T}(T) is known or vice versa. Following the recipe, the hemispherical total emissivities for each sample at its melting temperature, {var_epsilon}{sub T}(T{sub m}), have been determined using c{sub p}(T{sub m}) values available in the literature. They are 0.15, 0.29, and 0.17,more » for Ni, Zr, and Si, respectively.« less