| 摘要 |
A fan 20 having an inlet hub diameter smaller than an outlet hub diameter comprises a plurality of blades 20a attached to a fan hub / disc 10 which is driven by a turbine, eg. of a gas turbine engine. The fan blades have a main dovetail portion 22 which slots in dovetail grooves 12 on the hub extending parallel to the axis 1 of rotation, and which supports centrifugal forces acting on the rear of the blade. The blade also has a sub-engagement portion 29 at a front end thereof which engages a spinner / nosecone 30 such that centrifugal forces acting on the front portion are transmitted to said spinner, and thereon to the hub. The sub-engagement portion may be of dovetail (or other) form extending in parallel or sloping relative to the rotational axis. The nosecone preferably has complimentary grooves 34 and a faucet portion 37. The hub-tip ratio is preferably 0 to 0.35. |
