ANALYSIS OF ECONOMIC EFFICIENCY OF USING FLAT-OVAL TUBES WITH INCOMPLETE FINNING IN CONDITIONS OF NATURAL DRAFT

The efficiency of air coolers, working in free convection mode is considered. The expediency of installing an exhaust tower over the heat exchange surface of the air cooler and its transfer to the mode of natural draft has been established. The possibility of using flat-oval tubes with incomplete finning in the designs of air-cooled devices with natural draft is noted. Variant calculations of the aircooling device on the basis of the most widespread in the market of Ukraine finned tubes in which the quantity of air necessary for maintenance of thermal power is provided only by an exhaust tower are carried out. Comparisons of the results of calculations show that the best technical and economic indicators have a variant of the air cooler based on flat-oval tubes with incomplete finning. The amount of capital costs for the manufacture of air cooler based on flat-oval tubes with incomplete finning is 47% less than the heat exchanger based on bimetallic tubes with rolled spiral finning and 2 times cheaper than the option of aircooler based on tubes with welded spiral fins or oval pipes with oval finning