STANDARDIZATION OF THERMAL EMITTANCE MEASUREMENTS. PART III.

NORMAL SPECTRAL EMITTANCE, 800-1400 K, Authors: Harrison, W.N. ; Richmond, J.C. ; Skramstad, H.K.

From the Energy Citations Database, OSTI IdentifierOSTI ID: 4830164

Technical Report, WADC-TR-59-510(Pt.III), National Bureau of Standards, Washington, D.C.,1961 Sep 01

ABSTRACT:

The equipment for direct measurement of normal spectral emittance was extensively modified by incorporation of a new external optical system that increased the amount of radiant energy available for measurement by a factor of about 10, and other associated changes. The test procedure was modified by incorporation of a zero line'' correction. The equipment was calibrated by means of sector-disk attenuators which passed known fractions of the radiant flux from a blackbody furnace. Working standards of normal spectral emittance were prepared, calibrated, and shipped. An equation relating the normal spectral emissivity of a metal to five other parameters of the metal, each of which makes a non-linear contribution to the emissivity, was solved for one set of data by long hand'' methods. Some progress was made in setting up a program for solution of the equation by use of an electronic computer. Equipment for the automatic recording of spectral emittance data in a form suitable for direct entry into an electronic computer, and on-line computation from spectral emittance data of total emittance or solar absorptance, was designed. Specifications for the equipment were prepared and bids received preparatory to placing an order for its procurement. (auth)

Exact spectral emissivity measurements for radiation thermometry (IR thermometry)

Modern emissivity measuring facility for industry-orientated calibrations developed at PTB

This news release is available in German.
CAPTION: Local variation of the directed spectral emissivity of a car paint sample at a wavelength of 4 µm, measured using a thermography camera. (IMAGE COURTESY PTB)
Industry and research are increasingly relying on non-contact temperature measurements with the aid of heat radiation, for example, for the reliable and reproducible drying of car paint.

In order to attain exact and reliable results, the emissivity of the measured surface has to be known. It can only be determined precisely in complex measuring facilities.

The Physikalisch-Technische Bundesanstalt (PTB) has developed a modern emissivity measuring facility for industry-oriented calibrations.

Infrared Spectral Emittance & Optical Properties of Yttrium Vanadate

Infrared Spectral Emittance and Optical Properties of Yttrium Vanadate
Phys. Rev. 169, 705 - 709 (1968)

by: H. E. Rast, H. H. Caspers, and S. A. Miller *
Infrared Division, Research Department, Naval Weapons Center Corona Laboratories Corona, California 91720

Received 13 November 1967
"ABSTRACT: The infrared spectral emittance E of single crystals of YVO₄ has been examined near 4.2 and 77°K in the wavelength range 4-125 micrometers..."
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* Formerly Naval Ordnance Laboratory, Corona, Calif.

DIRECTIONAL SPECTRAL EMITTANCE OF A PACKED BED...

DIRECTIONAL SPECTRAL EMITTANCE OF A PACKED BED WITH COUPLED CONDUCTION-RADIATION HEAT TRANSFER

Dominique Baillis
Centre de Thermique de Lyon (CETHIL), UMR CNRS 5008, Institut National des Sciences Appliquées de Lyon, France

Jean-Francois Sacadura
Centre de Thermique de Lyon (CETHIL), UMR CNRS 5008, Institut National des Sciences Appliquées de Lyon, France

ABSTRACT

Recently a new experimental set up for measuring the directional spectral emittance has been developed. The both sides of packed bed sample are simultaneously heated with identical power laser beams (4kw, CO² 10.6 um) and the isothermal condition in the medium is assumed. In this paper, the coupled conduction-radiation equations are considered to investigate the effect of the temperature non-uniformity on the calculated value of the emittance and to verify if the isothermal assumption is valid. It is shown that the gradient temperature in the medium can be non negligible depending on the thickness and on the sample extinction coefficient.

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Spectral emittance of nickel and oxide-coated nickel cathodes

The spectral emittance of nickel- and oxide-coated nickel cathodes
S L Martin et al 1950 Br. J. Appl. Phys. 1 318-324

"Abstract. The spectral emittance values at a wavelength ? = 0.66 ? have been measured for various types of oxide-coated cathode, and for nickel cores, using a cylindrical diffuse reflectometer..."