A Numerical Study of Quad-Section Air Preheater Thermal Performance and Air Leakage

Abstract

This paper established a thermal and air leakage calculation model of quad-sectional rotary air preheater, which considered the axial heat conduction of the matrix and the effect of three kinds of air leakage-radial, axial and circumferential air leakage. Based on control equation of rotary air preheater, thermal calculation model was simplified and solved by numerical finite difference method. Air leakage model was solved by nonlinear equations based on mass and energy equations. With the coupling calculation of two models, temperature and air leakage distribution were given. Compared with a quad-sectional rotary air preheater, the error value was less than 5%. The results showed that air leakage of quad-sectional air preheaters was much less than tri-sectional ones .The temperature distribution of fluids in different air channels were continuous and were quite consistent with matrix. Declining the inlet gas flow along the direction of rotary can reduce the low-temperature area rate.