Heat dissipation fan

1. A heat dissipation fan, comprising:

a body including a fan air inlet surface, a central shaft driving surface located inside the fan air inlet surface, and a plurality of protrusion structures configured at spacings in a circumference direction of the central shaft driving surface; and

fan blades including first fan blades connected between the central shaft driving surface and the fan air inlet surface, and second fan blades connected between the protrusion structure and the fan air inlet surface;

wherein a fan air inlet angle is formed between each fan blade and the central shaft driving surface, and the plurality of protrusion structures are configured to vary the fan air inlet angle to control a flow field of an airflow entering the fan air inlet angle.

2. The heat dissipation fan according to claim 1 , wherein:

each of the plurality of protrusion structures is a crescent-shaped protrusion structure.

3. The heat dissipation fan according to claim 2 , wherein:

the plurality of protrusion structures are symmetrically arranged in the circumference direction of the central shaft driving surface.

4. The heat dissipation fan according to claim 3 , wherein:

a radius of the crescent-shaped protrusion structure is about 0.5 to 0.8 times a radius of the central shaft driving surface.

5. The heat dissipation fan according to claim 1 , wherein:

respective fan air inlet angles corresponding to the first fan blades are identical.

6. The heat dissipation fan according to claim 1 , wherein:

respective fan air inlet angles corresponding to the second fan blades vary regularly according to a preset curve relationship.

7. The heat dissipation fan according to claim 1 , wherein:

outer ends of the fan blades are distributed at equal spacings to connect to the fan air inlet surface.

8. The heat dissipation fan according to claim 1 , wherein:

the fan air inlet angle corresponding to an initial second fan blade is identical to the fan air inlet angle corresponding to any one of the first fan blades, the initial second fan blade being adjacent to one of the first fan blades.

9. A method of determining a position of a fan blade in a heat dissipation fan, the heat dissipation fan including a body including a fan air inlet surface, a central shaft driving surface located inside the fan air inlet surface, and a plurality of protrusion structures configured at spacings in a circumference direction of the central shaft driving surface, and fan blades including first fan blades connected between the central shaft driving surface and the fan air inlet surface, and second fan blades connected between the protrusion structure and the fan air inlet surface, and the method comprising:

determining a first fan air inlet angle and a quantity of the plurality of protrusion structures, the first fan air inlet angle formed between each first fan blade and the central shaft driving surface being identical for all the first fan blades;

identifying the first fan air inlet angle to be a second fan air inlet angle corresponding to an initial second fan blade, the initial second fan blade being adjacent to one of the first fan blades;

determining a third fan air inlet angle corresponding to each second fan blade based on a connection sequence of the second fan blades on each of the plurality of protrusion structures, the second fan air inlet angle, and the quantity of the plurality of protrusion structures, the third fan air inlet angle varying for different second fan blades; and

determining the position of each first fan blade based on the first fan air inlet angle and the position of each second fan blade based on the third fan air inlet angle.

10. The method according to claim 9 , wherein:

determining the position of each second fan blade based on the third fan air inlet angle includes:

determining a first connection position between an outer end of each second fan blade and the fan air inlet surface based on an equal spacing rule; and

determining a second connection position between an inner end of the second fan blade and each corresponding protrusion structure based on the third fan air inlet angle corresponding to the second fan blade.