Medidas de temperatura absoluta de radiación con radiómetros de filtro con sistema de enfoque

  1. Mantilla Amor, José Manuel
Supervised by:
  1. María José Martín Hernández Director
  2. José Juan Segovia Puras Director
  3. Joaquín Campos Acosta Director

Defence university: Universidad de Valladolid

Fecha de defensa: 22 April 2015

Committee:
  1. María Dolores del Campo Maldonado Chair
  2. Alicia Pons Aglio Secretary
  3. Klaus Anhalt Committee member
  4. Miguel Ángel Villamañán Olfos Committee member
  5. Emma R. Woolliams Committee member
Department:
  1. Energy and Fluidmechanics Engineering

Type: Thesis

Abstract

Currently, the dissemination of the Kelvin, according to the International Temperature Scale (ITS-90), at high temperatures is realised at the Centro Español de Metrología (CEM) by using the fixed points of Ag and Cu and a standard radiation thermometer. Recently, new alternatives have been proposed by the CCT Working Group 5 that will be included in future revisions of the Mise-en-Practique for the Kelvin (MeP-K). As absolute radiometry is at present able to achieve uncertainties competitive with the ITS-90 above the silver point, or even better, a primary dissemination of the thermodynamic temperatures is a reality, being one of the possible ways to calibrate for radiance responsivity an imaging radiometer (radiance method). In order to carry out this calibration, IO-CSIC (Spanish Designated Institute for luminous intensity and luminous flux) has collaborated with CEM, allowing traceability to its cryogenic radiometer. In a first step, a monochromator integrating-sphere based spectral comparator facility has been used to calibrate one of the commercial CEM standard radiation thermometers. The radiance of the sphere has been determined using two high precision apertures and a Si trap detector as a transfer standard. However, the uncertainty of these measurements is high. The reason is because this commercial radiation thermometer has to be spectrally calibrated by using a facility based on a monochromator and a high stability lamp which results in higher uncertainties. In order to reduce them, it could be used a laser based facility instead, but, when calibrating commercial radiation thermometers, interference fringes were detected, resulting in a ripple in the spectral distribution of the radiation thermometer. In consequence, CEM and IO-CSIC have developed filter radiometers whose design allows the laser based calibration. In this new design, some other considerations have also been taken into account: low size of source effect, high amplifier stability, temperature control system, etc. The absolutely calibrated standard radiation thermometer and filter radiometers has been used to determine the thermodynamic temperatures of the fixed points of Cu, Co-C, Pt-C and Re-C and the uncertainties have been determined. This Thesis describes the development of the CEM-IO-CSIC consortium filter radiometers, the set-ups used for its characterization and calibration (including commercial radiation thermometers), the uncertainty budgets and the absolute temperature measurements results.