Abstract: A mathematical model based on analytical numerical mixed computation method is established to simulate the thermal process in boiler heating surface. The tube wall temperature is determined first, then the energy conservation equations of cold flow and hot flow are decoupled and solved by inserting the tube wall temperature into the two equations. The cold start of a 600 MW supercritical pressure boiler is simulated with the proposed method. The calculated results are in good agreement with the measured ones. It is also found that the calculated results are similar with those obtained from iteration solving method, but the computation time shortens greatly for the analytical-numerical mixed computation method.

Key words: Analytical solution, Boiler heating surface, Dynamic process, Numerical solution