THERMAL SCIENCE

International Scientific Journal

A RELATIVE HUMIDITY CALIBRATION FROM 5°C TO 45°C IN A MIXED-FLOW HUMIDITY GENERATOR

ABSTRACT
The paper presents a method used in the Vinča Institute of Nuclear Sciences for a reliable and traceable relative humidity calibration in the temperature range from 5°C to 45°C. Inside a controllable temperature and humidity environment, supplied by a mixed-flow humidity generator, measurements of hygrometers under calibration are compared with those of calibrated reference instruments. A traceability chain from temperature to reference relative humidity and next to the hygrometers under calibrations is provided by using a chilled-mirror dew-point temperature system and precise relative humidity probes. Corresponding calibration uncertainties are analyzed, particularly those associated to the temperature uniformity of controlled calibration environment. Two examples of relative humidity calibration with dew-point and relative humidity reference measurements in the range from 15 to 75% of RH and 5°C to 45°C are presented and discussed.
KEYWORDS
PAPER SUBMITTED: 2011-06-01
PAPER REVISED: 2011-12-21
PAPER ACCEPTED: 2011-12-30
DOI REFERENCE: https://doi.org/10.2298/TSCI1201193M
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2012, VOLUME 16, ISSUE 1, PAGES [193 - 205]
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© 2021 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence