SU1143993A1 - Method of measuring temperature difference - Google Patents

Abstract

METHOD OF MEASURING THE DIFFERENCE OF TEMPERATURES, which consists in measuring the temperature at one of the controlled points on the body surface and determining the temperature difference from the intensities of thermal radiation from the indicated points on the surface, measured by the radiation receiver in a narrow spectral interval, which is different from the accuracy of , the difference between the monochromatic intensities of thermal radiation of selected points on the surface of the body is measured, and their temperature difference is calculated by the formula di-die-ECL LTg rd e T is the measured temperature at one of the surface points o body S, (L is the effective wavelength-, C, C, - first and second constants in the Plancki formula, respectively - the signal at the output of the 4 radiation receiver, proportional to the monochromatic difference about ordinary intensities; E - the emissivity of the body.

Description

eleven

The invention relates to the field of pyrometry and can be used primarily for measuring small temperature differences of semi-transparent materials, for example, quartz glass.

A known method for measuring the temperature difference across a layer of translucent material consists in measuring the ratio of radiation intensities at selected points for the visible and infrared regions of the spectrum and then determining the desired value using the calibration curve til

The disadvantages of this method are the low accuracy of measuring small temperature differences not exceeding 10-20 K and the need for it. Calibration on the blackbody model.

The closest to the invention to the technical essence is

, a method for measuring the temperature difference, consisting in measuring the temperature of one of the controlled points on the body surface and determining the temperature difference from the intensity of thermal radiation from the specified surface points measured by the radiation receiver in a narrow spectral interval 22.

The disadvantage of this method is the large measurement error, due to the fact that the measured temperature difference is determined by the logarithm of the ratio of the absolute values of the radiation intensities from two points.

The aim of the invention is to improve the accuracy of measuring the temperature difference.

This goal is achieved in that according to the method of measuring the temperature difference, which consists in measuring the temperature at one of the controlled points on the body surface and determining the temperature difference from the intensities of thermal radiation from these points on the surface, measured by the radiation receiver in a narrow spectral interval, measure the difference in monochromatic intensities thermal radiation of selected points on the surface of the body, and their temperature difference is calculated by the formula

 I AU-uUe -EC.A-) .u gcyrM

LT

di di -e A-5

i-t, en.

where TQ is the measured temperature

in one of the points of the body surface-,

 - effective wavelength; C, C - respectively, the first and

second constants in odds Mule Planck;

"

. whether it is a signal at the output of a radiation receiver proportional to the difference in monochromatic intensities; E is the emissivity of the body.

The drawing shows a diagram of an apparatus for carrying out a method for measuring a temperature difference.

The device contains flat rotating mirrors 1-3, modulating mirror 4 with electromechanical actuator 5, heat radiation receiver 6, recording equipment 7.

The thermal radiation fluxes from selected points A and B of the surface of the heated body 8, for example, a quartz glass sample, are alternately directed to radiation receiver 6 using mirrors 1-3 and modulating mirror 4. The thermal radiation streams switching module 1M by mirror 4 is performed in this way so that the indicated streams are shifted in phase by ISO relative to each other. In this case, the output of the receiver 6 separates the signal & U proportional to the difference in monochromatic intensities of heat fluxes from points A and B. The temperature value Td required for the subsequent calculation of the LT value one of the points can be obtained by any known method of temperature measurement, for example using a pyrometer 9.

Using the proposed method of measuring the temperature difference allows significantly (by a factor of 3-5) to increase the measurement accuracy by comparison J11439934

with the known. Thus, for example, not 40-50 K for K systems, if measuring the temperature difference, the measurement error of the non-quartz glass sample is 1-1.5%.

Claims (1)

METHOD FOR MEASURING TEMPERATURE DIFFERENCE, which consists in measuring the temperature at one of the controlled points on the body surface and determining the temperature difference from the intensities of thermal radiation from the indicated surface points, measured by a radiation receiver in a narrow spectral range, characterized in that, in order to increase the measurement accuracy, measure the difference of monochromatic intensities of thermal radiation of selected points on the surface of the body, and their temperature difference is calculated by the formula t-2 Λ _p ^{0 C} 2 AT = -------- AU-AU e ^ -ES A ' ^? AUe ^ -AU-EC ^ ^-5 -5 ' -sh 'AU-AUe ^w -EC ₄ A. AUe ^ -AU-EC ^ ' ⁵ -t where T _o is the measured temperature at one of the points on the surface of the body ·, the effective wavelength ·, respectively, the first and second constants in the Planck formula; Yu - Λ sc, s ₂ signal at the output of the radiation receiver, proportional to the difference of monochromatic intensities; body emissivity. SU „1143993