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.
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