Abstract:

In order to assess the ash deposition performance of flue gas flowing through the H-type finned tube economizer, a cold numerical simulation was carried out. The unidirectional coupling model was adopted to solve the gas particle flow by ignoring the influence of the solid phase on the gas phase. The flow field was obtained and thoroughly  analyzed under the condition of given inlet velocity and particle mass concentration. Results showed that the velocity profile was M-type on the windward side and W-type on the leeward side of the H-type finned tube. The seams of the H-finned tube had an axial sweep effect at the stagnant point on the windward side and could enhance the backflow turbulence on the leeward side, which could be helpful  to alleviate ash deposition on the H-finned tube. In addition, simulations under different inlet velocities  and particle mass concentrations  were carried out. Calculation results indicated that the H-finned tube had excellent anti-deposition performance under higher inlet velocity and particle mass concentration.

Key words: H-finned tube, gas-solid flow, numerical simulation, ash deposition, backflow