An Economizer Design

Abstract

The rapid increase in the world population, the development of technology, innovations and the increase in the development of many countries in parallel with industrialization have also increased the energy demand. Effective and efficient use of decreasing energy resources is of great importance. In this study, economizer design, theoretical calculations and numerical analysis were made by using the heat of the waste flue gas from the furnace. In the design, the data of the combustion test furnace used in a cable company were used.  The mean logarithmic temperature difference and ε - NTU methods were used in the economizer design calculations. As a result of the calculations, a 6-pass and 5-row economizer with a surface area of 288.24 m² and consisting of 120 self-finned serpentines was designed. The efficiency of the heat exchanger used in the economizer was calculated as 0.71. The water in the 500-liter boiler tank at 20°C was increased to 60°C in 435 seconds with the designed economizer. When the economizer is included in the system, it is seen that the flue gas temperature decreases from 71.2°C to 50°C. Thus, the flue gas will be cooled and thrown into the atmosphere at a lower temperature. The designed and theoretically calculated economizer was analyzed in the ANSYS CFD program with the finite element method. It has been seen that the results of the theoretical calculations and the numerical analysis are in harmony.