Study of Heating Devices Based on a First-Order Phase Transition

New developments aimed at saving costs for heating a house are attracting more and more attention. The development of highly efficient heating radiators that meet the requirements of modern engineering systems, namely: cost-effectiveness, efficiency, rapid uniform heating of the entire surface, ease of installation and operation, low manufacturing costs and durability is the main direction in the design of heating devices. In recent years, the use of heating radiators based on first-order phase transition has been gaining ground in heating systems in Ukrainian cities. In the literature and on the Internet resource s , there is another name for such kind of the radiators – vacuum radiators. T hey were named because air was completely pumped out of the internal cavity of the sectional structure. This is done in order to reduce the pressure and, accordingly, reduce the evaporation temperature of the secondary coolant. These are ordinary heating appliances externally, but completely different in principle of operation. In fact, the operation of the vacuum radiator is built on the principle of functioning of a sealed two-phase thermosiphon. The main advantage of such solution is the unique coolant circulation system. They can be used both for heating systems and for autonomous ones. There are conflicting opinions about the advisability of using vacuum radiators, so their confirmation or refutation requires in-depth research. This paper presents the results of experimental studies of a heating radiator based on first-order phase transition. As a secondary coolant, a liquid with a low boiling point is used. The principles of operation of the heating device are investigated, thermal capacities are determined at various temperatures of the coolant. A comparison is made with traditional steel and aluminum radiators, . Particular attention was paid to the study of vacuum radiators from the point of view of heat exchange, and their unusual properties were noted. The main advantages and disadvantages of this heating device are revealed. The ways of further research of these types of heating radiators are indicated.