Merilna negotovost in časovna konstanta meritev relativne vlažnosti z merilnikom Vaisala HMP155

Kozelj, Timotej (avtor), Skok, Gregor (mentor), Svetličič, Marko (komentor)

Cilj naloge je bil ovrednotiti merilno negotovost in časovno konstanto meritev rela- tivne vlažnosti z merilnikom Vaisala HMP155. To je merilnik, ki je v merilni mreži Agencije Republike Slovenije za okolje (ARSO) uporabljen za izvajanje meritev tem- perature in relativne vlažnosti zraka. Umeritev treh instrumentov je bila izvedena v umerjevalnem laboratoriju na ARSO. Merilna negotovost je bila ovrednotena v ob- močju relativne vlažnosti zraka od 20 do 95 odstotkov na temperaturnem razponu med -10 ◦C in 40 ◦C. Meritve relativne vlažnosti zraka so bile opravljene v generatorju vlažnosti in uporabljena je bila primerjalna metoda kalibracije. Merjenci so odstopali od refe- renčnega merilnika od −0,2 do 11,0 odstotkov, pri čemer so bila največja odstopanja pri najnižji temperaturi, pri višjih temperaturah so bila odstopanja občutno manjša. Merilne negotovosti so bile v območju od 1,0 do 2,4 odstotka, kjer so bile pri niz- kih temperaturah negotovosti bile večje od vrednosti v tehnični dokumentaciji, pri temperaturah nad 20 ◦C pa so bile približno enake kot v dokumentaciji. Meritve časovne konstante so bile izvedene ob spremembi relativne vlažnosti s 40 na 95 odstotkov in obrnjeno. Povprečna vrednost časovne konstante je bila 11,69 sekunde, kar je manj od navedene vrednosti v tehnični dokumentaciji.

• Jezik: Slovenski jezik
• Ključne besede: meteorologija, meritve, kalibracija, relativna vlažnost, merilna negotovost, časovna konstanta, Vaisala HMP155
• Vrsta gradiva: Zaključna naloga
• Tipologija: 2.11 - Diplomsko delo
• Organizacija: FMF - Fakulteta za matematiko in fiziko
• Leto izida: 2021
• PID: 20.500.12556/RUL-127850
• COBISS.SI-ID: 68668931
• Datum objave v RUL: 25.06.2021

Sekundarni jezik

• Jezik: Angleški jezik
• Naslov: Measurement Uncertainty and Time Constant of Relative Humidity Measurements with Vaisala HMP155 Probe

Izvleček

The goal was to evaluate the measurement uncertainty and time constant of relative humidity measurements with a Vaisala HMP155 probe. These probes are used in the observation network of the Slovenian environmental agency (ARSO) to perform measurements of temperature and relative humidity. Three instruments were cali- brated in the calibration laboratory at ARSO. The measurement uncertainty was evaluated in the range of relative humidity from 20 % to 95 % in the temperature range between -10 ◦C and 40 ◦C. Measurements were performed in a humidity generator, and a comparative ca- libration method was used. The tested instruments deviated from the reference meter by −0.2 to 11.0 percent. The largest deviations were at the lowest tempe- rature, while the deviations were significantly smaller at higher temperatures. The measurement uncertainties ranged from 1.0 to 2.4 percent. At low temperatures, the uncertainties were higher than the values given in the technical documentation, while at temperatures above 20 ◦C they were approximately the same as in the do- cumentation. Time constant measurements were performed with a sudden change in relative humidity from 40 to 95 percent and vice versa. The average value of the time constant was 11.69 seconds, which is less than the value stated in the technical do- cumentation.

• Ključne besede: Calibration, time constant, relative humidity, measurement uncertainty, meteorology, Vaisala HMP155