Trends in the Design and Manufacture of Round-Tube Plate-Fin Coils from Smaller Diameter Copper Tubes
Aggressive environmental legislation has motivated the design of ACR appliances that use low- or ultra-low GWP refrigerants and yet deliver high system efficiency. To achieve these design criteria, heat exchanger engineers have sought to increase the capacity of heat exchanger coils without increasing the materials usage and overall weight. In response, tube makers began supplying smaller-diameter copper tubes with a wider range of surface enhancements.
Concurrently, equipment manufacturers have redoubled their efforts to produce manufacturing equipment to handle high volumes of smaller diameter tubes; and the availability of small-diameter tube technology also stimulated the development of computer simulation tools to optimization of tube circuitry and fin geometries. Both of these developments were covered in a 2013 IAM white paper [1].