Through numerical calculation

the impact regularity of fly ash particles onto smooth tube bundles with in-line arrangement has been studied. The affecting factors selected are tube diameter

velocity of flue gas

particle size of fly ash

transversal and longitudinal tube-pitch etc. respectively

the dimensionless correlation equation of fly ash particles’ passing through rate and of the impacting rate being established. Combined with empirical formula obtained by the predecessors

a calculating equation for worn-out quantity of the smooth tube bundles with in-line arrangement resulting from fly ash partiches has been obtained. This result of study can provide design bases for horizontal tube bundles of the air preheater

superheater

reheater

and economizer with in-line arrangement in the tail section of CFB boilers.