Under condition of tower mass flow rate

the hydrodynamic calculation of water - wall tubes in 600 MW supercritical circulating fluidised bed (CFB) boiler adopting four kinds of once - through up - flow tube

namely austenitic steel smooth tube

carbon steel smooth tube

four - thread refled tube

and single - thread refled tube

has been carried out Results show that : (1) decreasing the frictional resistance coefficient of water - wall tubes can slow down the beat deviation

and decrease the total preasure drop ; (2) Along with increasing the distance deviated from center tube

the heat deviation of four kinds for water - wall tubes all to be lowered

the frictional pressure drop and the acceleration pressure drop also to be gradually lowered

but the weight pressure drop to be gradually increased; (3) along with incressing the distance deviated from center tube

the varying tendency of flow rate deviation for austenitic steel smooth tube to be gradually lowered * the flow rate deviation of carbon steel smooth tube to be increased first

find to be lowered later

but the flow rate deviation of four-thread and signle - thread rifled tubes all to be gradually increased.