Session 19: Metrology in Thermal Sciences

Chairs:

Alcir de Faro Orlando
Pontificia Universidade Católica do Rio de Janeiro

Edson Del Rio Vieira
Unesp

João Nildo Vianna
Universidade de Brasília Departamento de Engenharia Mecânica

Luís Fernando Alzuguir Azevedo
Departamento de Engenharia Mecânica PUC-RIO






s19p02

TECHNICAL ASPECTS OF CALIBRATION AND CHARACTERIZATION OF INFRARED PYROMETERS (SINGLE WAVEBAND TYPE) AND A PROPOSAL OF A TECHNICAL NORMATIZATION

Juliano Augusto Dillenburg - [email protected]
Universidade Federal do Rio Grande do Sul, Departamento de Engenharia Nuclear
Av. Osvaldo Aranha 99, 4º andar, CEP: 90460-900 Porto Alegre, RS, Brasil.

Milton Antonio Zaro - [email protected]
Universidade Federal do Rio Grande do Sul, Departamento de Engenharia Mecânica
Rua Sarmento Leite, 425, CEP: 90050-170, P. Alegre, RS, Brasil.

Horácio Antonio Vielmo - [email protected]
Universidade Federal do Rio Grande do Sul, Departamento de Engenharia Mecânica
Rua Sarmento Leite, 425, CEP: 90050-170, P. Alegre, RS, Brasil.

Calibration and characterization procedures for single waveband infrared pyrometers are proposed. Regardling the fact that doesn't exist a brazilian normatization and  the fact that the international normatization ASTM E1256-95 is incomplete, it's expected that these considerations will produce a discussion about the creation of a brazilian normatization for the use of such technique.

Keywords: Calibration, Temperature, Pyrometry, Emissivity, Radiation.
 
 



s19p03

QUALIFICAÇÃO METROLÓGICA DE UM HIGRÔMETRO DE MICROONDAS

HELBER S.HUAQUIPACO - e-mail [email protected]
ALCIR F.ORLANDO - e-mail [email protected]
Pontifícia Universidade Católica do Rio de Janeiro - PUC-Rio
Departamento de Engenharia Mecânica
R.Marquês de S. Vicente 225, Gávea, 22453-900, Rio de Janeiro, Brasil

ALBERTO J.F.Orlando - e-mail [email protected]
Instituto Tecnológico de Aeronáutica
Departamento de Engenharia Eletrônica

LUIZ C.CIPRIANO -
INMETRO

The water content in air or in other gases is important for controlling biological, chemical and physical processes, Measurements are made in industry within a wide range of humidity. They contribute to the composition of the final cost and quality of products, health and safety. The present work deals with a measurement technique for the water content in air. The resonance frequency of a rectangular cavity, designed for a fundamental frequency of 2,45 GHz (dry air), was measured by a spectrum analyser for different values of the water content. A standard dew point apparatus was used in INMETRO for measuring the partial pressure of water vapor in air inside the cavity. The partial pressure of water vapor in air was calculated by na existing theory as a function of temperature and resonance frequency of the cavity, and it was compared to the measured one. The resulting second degree polynomial curve fit between the two values reflects the deviation from ideality of the real cavity, suggesting that all cavities should be calibrated before being used. The uncertainty of measurement was estimated together with the influence of several parameters on the equipment response, which was compared to the available ones. This completes the metrological qualification of the device. As a result, it was demonstrated that the uncertainty of the dew point measurement by the standard apparatus is the parameter that mostly affects the overall uncertainty of the calibration.