The study on heat transfer model of tri-sectional rotary air preheater based on the semi-analytical method

Even though tri-sectional thermal regenerators are applied in power plant all over the world due to its compactness and better performance, low temperature erosion is still one of the biggest hurdles to be overcome. To prevent the erosion problem at the cold end, the temperature distribution in the regenerator must be determined. In the present investigation, a semi-analytical method is employed to investigate the three-dimensional heat transfer of a tri-sectional rotary air preheater. Special attention was placed on the temperature change of fluids and temperature distribution in the matrix of the preheater. The simulation results indicate that the semi-analytical approach is more precise and has better convergence than that of the standard numerical iterative method. The numerical analysis and experimental results show a significant dependence on the reduced length and reduced period of the rotary air preheater.