Термічний опір

Experimental samples of flat-oval thermosyphons (TS) with partial transverse rectangular and corrugated finning and samples of round TS with inner intensifiers of heat transfer in evaporation section (ES) were developed and fabricated. They are intended for functioning in heat exchangers (HE) utilizers of heat wastes in ventilation systems. It was shown, that freon R134a is the most optimal heat carrier for TS functioning in conditions close to these in ventilation systems from the point of boiling temperature and safety of application.

For the first time a comprehensive study of the processes of heat transfer and hydrodynamics during evaporation and condensation in closed miniature two-phase systems was carried out. The regularities of the influence of geometric and regime factors on the thermal resistance and maximum heat fluxes of miniature heat pipes, thermosyphons and pulsating capillary heat pipes are revealed. The physical model of heat exchange processes in the conditions of limited space at application as heat carriers of ordinary liquids and nanofluids is developed and presented.

A complex study of heat transfer processes in constrained conditions in evaporative-condensation systems was carried out for the first time. A physical model of the boiling process on porous surfaces in conditions of limited space was developed and presented. Dependencies for calculating the heat transfer intensity under such conditions have been obtained. Such dependencies are necessary to create miniature cooling systems for microchips and powerful processors of electronic equipment.

Up to 30% of the produced electricity is being spent on the lighting in Ukraine. Therefore, the problem of energy saving in lighting stands very seriously. Introduction of energy-saving technologies in the internal lighting systems will provide significant energy savings and improve the ecological condition by reducing atmospheric discharges of thermal power plants.