Vpliv medija na merjenje temperature v komori

VOROŠ, DAMJAN (author), Pušnik, Igor (mentor)

S temperaturno komoro simuliramo temperature, katerim so lahko izpostavljeni vzorci, pri katerih potekajo reakcije, ipd. Kar nekaj vzorcev shranjujemo v različnih medijih (snovi kot nosilcu fizikalnih ali kemijskih procesov) in tudi reakcije potekajo v njih. Vprašanje, ki se pojavi, je, ali je temperatura medija enaka nastavljeni temperaturi temperaturne komore oziroma kolikšno je odstopanje. V ta namen smo z diplomskim delom želeli pokazati, kako medij vpliva na merjenje temperature v temperaturni komori. Zasnovali smo eksperiment. Za eksperiment smo si izbrali 3 medije, in sicer silikonsko olje, glicerin ter najbolj pogosto uporabljen medij – vodo. Izbrali smo tudi 3 različne posode, v katere smo nalili medije, to so erlenmajerica, epruveta in čaša. Odločili smo se, da bomo eksperiment izvedli pri 4 različnih temperaturah (37 °C, 50 °C, 70 °C in 105 °C). Eksperiment smo izvedli v temperaturni komori Binder FED 204. V temperaturno komoro smo razporedili in namestili 18 platinastih uporovnih termometrov, pri čemer smo z 9 merili temperaturo okolice in z 9 temperaturo različnih medijev v različnih posodah. Predhodno smo tudi preverili, ali so termometri spremenili kazanje od zadnjega umerjanja. Merjenje temperature je bilo izvedeno s pomočjo LabVIEW programa, uporabili smo Keithley 7001 preklopnik in ohmmeter. Tako merjenje temperature smo ponovili 4-krat, za vsako nastavljeno temperaturo temperaturne komore. Pri vsaki nastavljeni temperaturi temperaturne komore smo komoro odprli za 2 minuti in zamenjali 2 termometra iz enega medija v drugega. Dodatno smo izvedli še eksperiment, kjer smo merili temperaturo vode v odprti in zaprti posodi. V tem primeru smo namesto platinastih uporovnih termometrov za merjenje temperature uporabili Betatherm NTC termistorje. Pridobljene meritve smo predstavili grafično in tabelarično. Ugotovili smo, da se temperatura izbranih medijev v izbranih posodah in temperatura komore razlikujeta. Temperatura silikonskega olja v čaši se najbolj približa temperaturi komore, medtem ko temperatura vode v čaši najbolj odstopa od temperature komore. Čim večja je površina odprte posode z vodo, tem nižja je njena temperatura.

• Language: Slovenian
• Keywords: temperaturna komora, merjenje temperature, temperaturni medij
• Work type: Undergraduate thesis
• Organization: FE - Faculty of Electrical Engineering
• Year: 2016
• PID: 20.500.12556/RUL-83111
• Publication date in RUL: 27.05.2016

Secondary language

• Language: English
• Title: Influence of medium on measurement of temperature in a chamber

Abstract

The temperature chamber simulates temperatures, to which samples may be exposed, temperatures at which reactions take place, etc. Many samples are stored in different media (substances for physical or chemical processes), as well as reactions take place in them. The question that arises is whether the average temperature is equal to a set temperature of a temperature chamber and to what extent it deviates from the set temperature. This led to the purpose of the diploma thesis. We wanted to show how the media affects the measurements of temperature in the temperature chamber. We designed the experiment. For the experiment we chose 3 media, silicone oil, glycerin and the most commonly used medium - water. We chose 3 different containers into which we poured the media (an Erlenmeyer flask, a test tube and a beaker). We decided that to carry out the experiment at 4 different temperatures (37 ° C, 50 ° C, 70 ° C and 105 ° C). The experiment was carried out in the temperature chamber Binder FED 204. 18 platinum resistance thermometers were set into the temperature chamber, 9 for measuring temperature of the chamber and 9 for measuring temperature of different media in various containers. Previously, we examined if the thermometers deviated from the last calibration. Temperature measurements were performed by using the LabVIEW program, the Keithley 7001 scanner and the ohmmeter. Thus, measuring of temperatures was repeated 4 times, for each of the set temperature of the temperature chamber. At each set temperature of the chamber the chamber was opened for 2 minutes and 2 platinum resistance thermometers were exchanged from one medium to another. Additionally, we performed the experiment where we measured the temperature of water in open and closed containers. In this case, we have used Betatherm NTC thermistors instead of platinum resistance thermometers. The measurement results are presented graphically and in tabular form. We found out that temperature of the selected media in a specific container differs from the temperature of the chamber. The temperature of silicone oil in the beaker is the closest to the temperature of the chamber, while the temperature of water in the beaker deviates the most from the temperature of the chamber. The greater the surface of opened container with water is the lower is the temperature of water.

• Keywords: temperature chamber, measuring of temperature, temperature medium