Open AccessProcedures for Verification of Instruments for Thermal Environment Measurement
Author(s) -
Ng Wai Tuck,
Sheikh Ahmad Zaki,
Fitri Yakub,
F L M Redzuan
Publication year - 2021
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/1051/1/012076
Subject(s) - hygrometer , relative humidity , standard deviation , environmental science , air velocity , temperature measurement , wind speed , airflow , thermocouple , measuring instrument , air temperature , accuracy and precision , meteorology , density of air , consistency (knowledge bases) , humidity , mathematics , statistics , engineering , mechanical engineering , electrical engineering , physics , mechanics , geometry , quantum mechanics , thermodynamics
Accuracy and verification of instruments for thermal environment measurement are important to determine the reliability of measured parameters. The purpose of this study is to propose simple procedures for consistency check on four groups of instruments used in thermal environment measurement: indoor air temperature, outdoor air temperature, relative humidity, and air velocity. For indoor air temperature measurement, the existing instruments were checked with the new thermocouple connected to a data logger in an air-conditioned room. The measurement was conducted under different set point temperatures. For relative humidity measurement, the readings of the measurement instruments were measured in a naturally ventilated room and compared with those of the digital ventilation psychrometer. For air velocity measurement, the instruments were set in a mini handmade wind tunnel. The air velocity readings obtained from the instruments were compared to verify the result consistency. Finally, for outdoor air temperature measurement, all instruments were placed in a fan aspirated solar shield which was set outdoors. For each group of the instruments, the obtained readings were evaluated based on the coefficient of determination and standard deviation from the mean values. The results have shown that all air temperature and relative humidity instruments have strong correlation owing to the high coefficient of determination obtained. The mean air velocity obtained from all measurement instruments ranged from 3.24 to 3.40 m/s with the standard deviation of 0.07 to 0.1. Furthermore, the mean outdoor air temperature ranged from 25.3 to 25.6°C with the standard deviation of 1.04 to 1.08. The simple procedures carried out in this work successfully verified the consistency of all measurement instruments, and this is essential before the instruments are used in actual field measurements.