Characterization of low-temperature liquid bath

Svrha ovog završnog rada je ispitivanje karakteristike niskotemperaturne kupke, koja je ispunjena etanolom, u temperaturnom rasponu od -70 °C do 10 °C, a koja će služiti u svrhu umjeravanja termometara. U sklopu završnog rada odrediti će se parametri koji imaju utjecaj na mjernu nesigurnost prilikom naknadnog usporednog umjeravanja termometara u promatranoj kupki. Ispitivanjem je obuhvaćeno određivanje radijalnih i aksijalnih gradijenata i temperaturna stabilnost, a provodi se prema metodi Laboratorija za procesna mjerenja, Fakulteta strojarstva i brodogradnje u Zagrebu. Metoda ispitivanja je opisana i objašnjena uz pripadajuće parametre i formule. Dobiveni rezultati ispitivanja su prikazani tablično, te je uz njih također opisana korištena oprema kao i sami postupak mjerenja.This bachelor's thesis aims to describe the experimental examination of characteristics of the low-temperature thermostated bath, which uses ethanol as a working fluid, in the temperature range from -70 °C to 10 °C. The bath is normally used as a zone of controlled temperature for calibration of thermometers by comparison. As part of this paper, parameters will be determined that have an impact on measurement uncertainty during the comparison calibration of the thermometers in the observed bath. These parameters include axial temperature gradients, radial temperature gradients, and temperature stability. The experimental work and analysis of the results are conducted by the procedures commonly used in the Laboratory of Process Measurements at the Faculty of Mechanical Engineering and Naval Architecture in Zagreb. The used equipment, characterization procedure, and related data analysis are described and explained, and relevant parameters and formulas are given together with the graphical and tabular representations of the results