Centrifugal fan, neck fan, and vortex shell assembly

A neck fan, configured to be worn around a neck of a user, comprising:

• a shell, configured to hang around the neck and defining an accommodating space inside the shell;
• a centrifugal fan, received in the accommodating space;
• a partition, extending along an extension direction of the shell;
• wherein, the partition and a part of an inner wall of the shell cooperatively form an air duct that is fluidly connected to the centrifugal fan;
• wherein, the centrifugal fan comprises a vortex tongue structure and a plurality of blades arranged inside the vortex tongue structure;
• the centrifugal fan is disposed at an end region of the accommodating space;
• and the vortex tongue structure is disposed at a central region of the end region of the accommodating space and is spaced apart from the inner wall of the shell.