| 摘要 |
In order to increase the lift supporting underpressure force on top of the inlet fairing of a shrouded fan of a lifting engine and in order to reduce the negative lift generating force of the inlet momentum acting on the rotor area of the fan, a particular geometry of the inlet fairing contour in connection with a particular twist of the fan rotor blades (3) is applied. This results in large differences of static pressures between front side and rear side of the fan at outer radii and there will be more small pressure difference at inner radii. This causes an apparent small change of the blade angle beta along a mean radial range of the rotor blades. Guide vanes ( 25) which might follow downstream of the fan rotor blades in some design cases, will have an arrangement of radial twist distribution mirror symmetrical to that of the rotor blades.
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