Diffuser, centrifugal compression power system and bladeless fan

A diffuser configured to be used in a bladeless fan, comprising:

• a lower element;
• and
• an upper element fixed on the lower element;
• wherein the upper element is above the lower element in a vertical direction of the diffuser, and airflow is guided by the lower element towards the upper element
• wherein the upper element and the lower element are formed separately;
• the lower element comprises a lower inner wall and a lower outer wall, and the upper element comprises an upper inner wall and an upper outer wall;
• the upper inner wall is connected to the lower inner wall to form an internal air-guiding surface;
• the upper outer wall is connected to the lower outer wall to form an external air-guiding surface;
• the internal air-guiding surface is disposed opposite to the external air-guiding surface, and an air-guiding channel configured to diffuse an airflow is defined between the internal air-guiding surface and the external air-guiding surface;
• the upper element further comprises an upper air-guiding wing for integrally connecting the upper inner wall and the upper outer wall, and the lower element further comprising a lower air-guiding wing for integrally connecting the lower inner wall and the lower outer wall;
• the upper air-guiding wing is connected to the lower air-guiding wing to form an air-guiding wing for connecting the internal air-guiding surface and the external air-guiding surface;
• wherein the lower end of the upper outer wall abuts the upper end of the lower outer wall;
• wherein the lower outer wall and the upper outer wall forms a outer wall, the lower inner wall and the upper inner wall forms an inner wall, both diameters of the outer wall and the inner wall decrease gradually from lower end of the diffuser to upper end of the diffuser;
• and p1 the inner wall is in shape of a cone, upper end of the inner wall forms vertex of the cone.