## 8 Results and Discussion
The best result was obtained with a working medium amount of 20%, when the cooling system removed a heating power of 818 W  
Figure 11: Measurement results at a heat load of 2000 W.  
from the electrical enclosure and the average operating temperature inside the electrical enclosure reached 43 \({}^{\circ}\)C.  
Figure 10 shows the results of heat transfer by means of a loop thermosiphon, the evaporating part of which was loaded with a simulated heat of 1500 W from electrical resistance bodies. The analysis of the results showed that the cooling device removed heating power in the range of 1157-1236 W with an average value of 1185 W and an average operating temperature inside the electrical enclosure in the range of 51-54.6 \({}^{\circ}\)C at all investigated volumes of working medium. In terms of power dissipation to the environment, no dependence of the effect of the amount of working fluid in the evaporator was observed. From the point of view of the temperature in the interiors of the cabinet, it can be stated that at a volume of 100%, the temperature was significantly higher than at a volume of the working substance in the range of 20-80%. The best result was obtained with a working medium amount of 20%, when the cooling system removed a heating power of 1200 W from the electrical enclosure and the average operating temperature inside the electrical enclosure reached 51 \({}^{\circ}\)C.  
Figure 11 shows the results of heat transfer by means of a loop thermosiphon, the evaporating part of which was loaded with a simulated heat of 2000 W from electrical resistance bodies. The analysis of the results showed that the cooling device operates at all variants of working fluid volume very well when the cooling device was able to remove heating power in the range of 1525-1581 W with an average value of 1549 W and an average operating temperature inside the electrical enclosure in the range of 57.5-59.7 \({}^{\circ}\)C. In terms of power dissipation to the environment, the dependence of the effect of the amount of working fluid in the evaporator was observed. In this case, a lower heating power dissipation was observed at the working fluid volumes of 60-100% than at the volumes of 20-40%. From the point of view of the temperature in the interiors of the cabinet, there was a temperature increase that was observed at volumes of 60-100%. The best result was obtained with a working medium amount of 20%, when the cooling system removed 1582 W from the electrical enclosure heating power of and the average operating temperature inside the electrical enclosure reached 57.5 \({}^{\circ}\)C.  
Overall, we can say that the proposed refrigeration equipment operated reliably under all tested conditions and achieved excellent results. Some dependence of the amount of working substance on the amount of heat removed was expected, but this was not clearly demonstrated. It is probable that the specially designed construction of the evaporator allows device uniform operation at different operating conditions. A slight decrease of the cooling effect was shown only in the case of a filling volume of 100%, when in all performed measurements, an increase in temperature was observed in the interiors of the cabinet, but not so much as to significantly affect the operation of electrical elements. Figure 12 shows the temperatures and pressure courses inside the enclosure at the heat load of 1000 W, working fluid amount of 80%, and with fans turned on inside the enclosure. At the beginning of the measurement, the enclosure was heated to a temperature of about 80 \({}^{\circ}\)C by supplying the heat load of 2000 W. Then, the supplied heat was reduced to 1000 W, and the fans inside the cabinet, which are meant to the direct the flow towards the evaporator, were turned on. Then, it can be seen that the temperature inside the enclosure rapidly decreased in a few minutes to 50 \({}^{\circ}\)C and gradually decreased in time to approx. 45 \({}^{\circ}\)C. This indicates that the cooling device operates and cools the interior enclosure.