Analysis of the exit angle of impeller blades in a fan

The exit angle of the impeller blades is the main factor affecting the formation of the ash. The exit angle of the blades is large, and the ash of the suction fan blades is less. Therefore, in the selection of the fan, the geometry of the suction fan blade should be considered.

The amount of ash accumulated in the fan blade is directly related to the adhesion strength of the solid matter in the flue gas. There are many types of flue gas solids, such as clay, alkali metal, sulfide, oxide, and salt. Through the analysis of the initial ash accumulation of the leaves, there are many components containing clay, alkali metal and sulfide. It indicates that the more clay, alkali metal and sulfide are contained in the flue gas, the faster the formation of the sediment of the suction fan blade. Once the ash is formed, the thickness of the ash increases rapidly, so that any solid matter can be deposited on the blade.

The dust particles in the boiler flue gas of the thermal power plant are finer, the finer the ash particles, the more uniform, the more the ash content of the suction fan blades. Moreover, the natural angle of repose of dust particles is also an important factor affecting the amount of dust accumulation. The smaller the natural angle of repose, the less the ash accumulation of the suction fan blades.

When the flue gas temperature drops to near or below the dew point temperature, the ash accumulation of the suction fan blades increases. The greater the dust concentration of the flue gas, the more dust is accumulated in the suction fan blades. The main reason is that the efficiency of the dust collector is reduced for some reason, and the dust accumulation of the suction fan blades is increased.