SU1413443A1 - Method of measuring thermodynamic temperature of bodies - Google Patents

Abstract

The invention relates to radiation pyrometry and can be used to measure the temperature of heated surfaces, including diffuse and diffuse reflecting surfaces, for example in metallurgy and ceramic production. The aim of the invention is to improve the measurement accuracy of bodies with a rough surface. The goal is achieved by the fact that in addition to measuring the body's own thermal radiation at two wavelengths and measuring the ratio of directional-directed spectral reflection coefficients normal to the pyrometric surface, the ratio of directional-directed spectral reflection coefficients is additionally measured for one of the corrections at an angle to the normal to the surface of the pyrometric body, the ratio of equivalent solid angles is determined, and based on the data obtained, the thermodynamic temperatures are calculated . (L

Description

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The invention relates to radiation pyrometry and can be used to measure the temperature of heated surfaces, including diffuse and diffuse reflecting surfaces, for example in metallurgy and ceramic production.

The aim of the invention is to improve the accuracy of measuring the temperature of bodies with a roughened surface.

The basis of the method of relative spectro reflectometry is the equation

de С, С;

, 5f,

S, L ,, L ,,

pyrometric constants;

used wavelengths; 25

the measured spectral densities of the energy luminance in the wavelengths I, and I;

T is thermodynamic body temperature;

p is the ratio of spectral directional hemispherical reflection coefficients p and f at wavelengths y and l However, in practice it is more convenient to use the ratio of directional directional instead of the ratio of directional hemispherical reflection coefficients, while measuring the temperature there is a methodical error associated with the spectral Difference in indicatrix of reflected radiation. The connection between the spectral directional-hemispherical and directional-directed reflection coefficients O and R (0) is made through an equivalent solid angle 5c as follows

J. R (0) I-.

where W is the solid angle of the receiver i-:

radiation.

The spectral ratio of normalized indicatrices Xj, (9) for different directions 9 to the normal links the ratio of spectral

15

20

25

thirty

35

Q.

:

the ratios of the directional reflection coefficients at the angle and normal to the surface

V ffl - Kr (9) Rig (6) fj.

GL - - R,., (&))

where index o refers to measurement

normal and index Q - 0 at an angle of 9 to the normal;

21, the ratios of the directional reflection coefficients) to R (TI,) or R (I,) to RjC p, respectively. In this expression, the directional-directed coefficients of the ratio, in turn, can be expressed in terms of equivalent solid angles and directional hemispherical reflection coefficients.

R / o)) u) -.

Perform this replacement, as a result we get

a,) - R, (.)

where 5 and J are equivalent solid angles with I and. Let us express the ratio of the spectral direction-hemispherical reflection coefficients in terms of the remaining values

j, R, (e) X ,, (9) ---. (4)

Yal

This shows that in order to determine the ratio of the spectral directional hemispherical reflection coefficients 1, it is necessary to measure the ratios of the spectral directional reflection coefficients at an angle S to the normal R, 2 (6) and normal to the surface R ;, - (O), determine according to in the chosen direction, the ratio of the spectral normalized indicatrices, set in accordance with the selected direction and the value of Xj, (0), the value of the ratio of equivalent solid angles 52 / S,. Using the obtained data set R (0), Xg (0) and 9j /, we determine the ratio of the spectral directional hemispherical reflection coefficients and, using the values of the measured spectral brightness L, and Lg for those

50

on the other hand, the wavelengths and Hj,, we calculate the thermodynamic temperature of the object being measured by formula (I).

Claims (1)

Thus, the proposed method makes it possible to determine the temperature of bodies with higher accuracy by taking into account the spectral difference in the indicatrix of the radiation reflected from the pyrometric surface. This will make it possible to effectively use the method in the process of measuring the thermodynamic temperature of bodies with a rough surface, for example, in ceramic production, metallurgy, during thermal strengthening of parts, in a scientific experiment. Invention Formula Method of measuring thermodynamic temperature of bodies, based on measurements five rhenium of the body’s own thermal radiation at two wavelengths, including the illumination of the object to be pyrometrized and the measurement of the spectral 6f-directional directional reflection coefficients at the same wavelengths normal to the pyrometry surface, in order to improve the accuracy of body temperature measurements with a rough surface, the spectral ratio of the directional reflection coefficients in one direction is additionally measured at an angle to the normal to the surface of the pyrometer forward body, the equivalent ratio determined solid angles and taking into account the data determined by the thermodynamic temperature.