Study on Structural Optimization Design of Heat Exchangers of Hot air furnace

Spraying heat exchanger and tubular radiation recuperator are common equipment of the drying hot air furnace. To study the way of reducing the investment cost for the heat exchanger of high-temperature and high-capacity hot air furnace, the heat exchange area of the two heat exchangers was calculated by LMTD method when air temperature rose from 0°C,100°Cand 200°C to different temperature points, and the figure of the relationship between the temperature difference and average heat exchange area was given. According to the analysis, the economical temperature range of the heat exchangers is narrower as the inlet air temperature rises. When the air temperature difference keeps constant, the average heat exchange area increases as the inlet air temperature rises. When the inlet air temperature keeps constant, the average heat exchange area increases gradually as the air temperature difference rises. Then the average heat exchange area exceeds the economical temperature range and approaches infinity quickly. The analytical method of economic performance can be applied to the design and model selection of two-stage heat exchanger of high-temperature and high-capacity hot air furnace.