This paper deals with the experimental research and verification of a passive cooling system operating on the principle of a loop gravity heat pipe designed for cooling electrical cabinets. This type of cooling works automatically by changing the state of the working substance and thus saves energy consumption. Since the designed cooling system ensures heat transfer from the interior cabinet to the outdoor space, where the heat can naturally dissipate to the surroundings, it is dustproof. The heat pipe consists of an innovative evaporator concept designed to minimize liquid and vapour phase interference in the refrigeration circuit. The aim of the research was to experimentally determine the limit performance parameters of the refrigeration system for different volumes of working medium in the evaporator and decrease heat loss in the cabinet interior. The designed device was verified experimentally and by mathematical calculations as well. The greatest benefit of the work is that the cooling device was able to ensure temperature conditions inside the electrical enclosure at a heat load of 2000 W under 60 °C, 1500 W under 55 °C, 1000 W under 50 °C, 750 W under 45 °C and 500 W under 40 °C.

Creating thermal well-being and comfort for humans is now very natural and necessary. From the point of view of ensuring optimal operating conditions for electronic and electrical equipment, it is very important to provide a cooling system. For this reason, the research work deals with the creation of optimal conditions for rising temperatures in rooms with electronics. A combination of cooling systems is proposed to reduce the heat load of electronic components. The first part of the work generally describes the requirements for the design of refrigeration equipment and methods of heat dissipation by natural or forced convection. Depending on the requirement for low-energy equipment, a cooling system with a gravitational heat pipe and fans was designed in the second part of the work. The cooling system was installed in a closed electrical cabinet. The resulting values of the measurements indicated the evaluation of the transferred heat output in free and forced convection. The research also points to a comparison of the individual flow directions created by the fans.