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Title: CRITIQUE ON THE ANALYTICAL REPRESENTATION OF SPECIFIC HEAT DATA. Period covered: January 1957 to August 1957

Abstract

A considerable lack of agreement exists in the literature for high- temperature specific heat values. Since the majority of these data have been obtained indirectly through enthnlpy measurements, the problem of data treatment is added to those of the experiment. It is thought that the present uncertainties in the methods of curve fitting the enthalpy data can yield misleading trends to the resulting specific heat curves. For this reason, it appears wise to consider the flnal result in the light of simple specific heat theory and the accuracy and reproducibility of the original enthalpy data. The complexity of the analysis should be based upon the reliability of the enthalpy data to avoid ''over-fitting.'' It appears that in the absence of exceptiomally precise enthalpy data, a quadratic expression will satisfactorily describe the data, resulting in a linear specific heat representation. This simple representntion is sometimes more compatible than those obtained by other means. (auth)

Authors:
Publication Date:
Research Org.:
Wright Air Development Center. Materials Lab., Wright-Patterson AFB, Ohio
OSTI Identifier:
4322047
Report Number(s):
WADC-TN-57-308
NSA Number:
NSA-12-004076
Resource Type:
Technical Report
Resource Relation:
Other Information: Project title: MATERIALS ANALYSIS AND EVALUATION TECHNIQUES. Task title: THERMAL MEASUREMENTS. (AD-142095). Orig. Receipt Date: 31-DEC-58
Country of Publication:
United States
Language:
English
Subject:
CHEMISTRY; DIAGRAMS; ENTHALPY; EQUATIONS; MATHEMATICS; MEASURED VALUES; SPECIFIC HEAT; THERMODYNAMICS

Citation Formats

Pawel, R. CRITIQUE ON THE ANALYTICAL REPRESENTATION OF SPECIFIC HEAT DATA. Period covered: January 1957 to August 1957. United States: N. p., 1957. Web.
Pawel, R. CRITIQUE ON THE ANALYTICAL REPRESENTATION OF SPECIFIC HEAT DATA. Period covered: January 1957 to August 1957. United States.
Pawel, R. Fri . "CRITIQUE ON THE ANALYTICAL REPRESENTATION OF SPECIFIC HEAT DATA. Period covered: January 1957 to August 1957". United States. doi:.
@article{osti_4322047,
title = {CRITIQUE ON THE ANALYTICAL REPRESENTATION OF SPECIFIC HEAT DATA. Period covered: January 1957 to August 1957},
author = {Pawel, R.},
abstractNote = {A considerable lack of agreement exists in the literature for high- temperature specific heat values. Since the majority of these data have been obtained indirectly through enthnlpy measurements, the problem of data treatment is added to those of the experiment. It is thought that the present uncertainties in the methods of curve fitting the enthalpy data can yield misleading trends to the resulting specific heat curves. For this reason, it appears wise to consider the flnal result in the light of simple specific heat theory and the accuracy and reproducibility of the original enthalpy data. The complexity of the analysis should be based upon the reliability of the enthalpy data to avoid ''over-fitting.'' It appears that in the absence of exceptiomally precise enthalpy data, a quadratic expression will satisfactorily describe the data, resulting in a linear specific heat representation. This simple representntion is sometimes more compatible than those obtained by other means. (auth)},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Aug 30 00:00:00 EDT 1957},
month = {Fri Aug 30 00:00:00 EDT 1957}
}

Technical Report:
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