EXPERIMENTAL PRODUCTION AND MODELING OF FINNED TUBES FORMATION BY FREEZING IN THE FORM WITH DISCRETE THERMAL INSULATION

Background. Air heating in winter in the range of ambient temperatures below -5 °C may be carried out by the heat of the phase transition of water into ice. Heated air reduces energy consumption in ventilation systems, in heat pumps such as air–water and air–air, in boilers and furnaces for fuel combustion, during peak loads on heat supply systems, that reduces the installed capacity of heat-generating equipment and save energy. Objective. The aim of the study is experimental research and computer simulation of technology for producing ice pipes with internal and external fins by discrete thermal insulation for transverse and longitudinal ribs. Methods. Air with a temperature below -5 °C is passed through ice finned from the inside pipes immersed in water or irrigated with water, for use heated to -2-3 °C air in ventilation systems, heat pumps, fuel combustion systems and in buffer zones of buildings during frost. Experimental work on the production of finned ice pipes in the freezer and modeling in SolidWorks has been carried out. Results. The obtained ring interior edges are rounded due to the lateral flow of heat and provide an opportunity to obtain the coefficient of the fins of 1.3-2. When applying the individual elements of the longitudinal insulation, the pipe is obtained with an internal cross-section in the form of a polygon with the number of angles corresponding to the number of elements. External ribs could not be formed experimentally when applying internal thermal insulation elements due to the low heat exchange of the pipe with the air inside the vertical pipe placed in the freezer. In the simulation result in the forced supply of air into the inner tube of the two insulation elements arranged symmetrically, the oval cross-section tube of ice was received. Conclusions. The lower the ambient temperature, the greater the economic and energy effect. Ice finned tubes should be used for heating frosty air and cold storage, for example, to create ice decorative vases, in which containers with drinks of different shapes are placed. This is an element of novelty for the hotel and restaurant business.