A new type of pulverized coal burner combining a bend with a rough surface taper 60 degrees bluff-body has been designed. The cold state test showed that behind the rough-surfaced bluff-body there exists a larger recirculation zone, recirculation ratio and stronger turbulence, but its pressure drop increases by about 15-20 per cent more than that of the smooth-surfaced bluff-body. The hot state test in a one-dimensional furnace indicates that the rough-surfaced bluff-body has much faster ignition, higher flame temperature and higher burnout ratio. A heat balance model was established using a lumped parameter method for the recirculation zone. Through it, the condition of the primary air was derived for flame stability and the strengthening combustion ability of rough surface in bluff-body was proved. On the basis of a hot state test, numerical stimulation was performed on NOx formation. This suggests that rough-surfaced bluff-body only increases the production of NOx a little. Copyright (C) 2001 John Wiley & Sons, Ltd.