Design and Test of Mixed-flow Impellers III : Design and Experimental Results for Impeller Model MFI-2A and Comparison with Impeller Model MFI-1A.

Author:: Hamrick, Joseph T
Published:: March 10, 1953.
Physical Description:: 1 electronic document
Additional Creators:: Beede, William L and Osborn, Walter M

Online Version

hdl.handle.net , Connect to this object online.

Availability

Finding items...

Restrictions on Access:: Unclassified, Unlimited, Publicly available.
Free-to-read Unrestricted online access
Summary:: A mixed-flow impeller was designed to give a prescribed blade-surface velocity distribution at mean blade height for a given hub-shroud profile. The blade shape at mean blade height, which was produced by the prescribed velocity distribution, was extended by means of radial lines to form the composite blade shape from hub to shroud. The resulting blade was relatively thick; therefore, it was necessary to retain the inverse blade taper which resulted from extension of the radial lines in order to prevent merging or near merging of the separate blades near the hub. For the first test version of the impeller, designated the MFI-2A, the blade height was arbitrarily made greater than that for the basic impeller (the MFI-2) to allow for viscous effects. At design equivalent speed of 1400 feet per second the peak pressure ratio and maximum adiabatic efficiency were 3.95 and 79 percent, respectively. The adiabatic efficiency of the MFI-2A is four points lower than that for impeller model MFI-1A, but because of the higher slip factor for the MFI-2A, the pressure ratios are approximately equal. The procedures followed in the design of the MFI-1A and MFI-2A were, in general, the same; and, although the prescribed initial condition resulted in geometrical configurations that were quite dissimilar, the resulting performance characteristics compare favorably with designs for which considerable development work has been necessary.
Collection:: NASA Technical Reports Server (NTRS) Collection.
Note:: Document ID: 19930087588.
Accession ID: 93R16878.
NACA-RM-E52L22a.
Terms of Use and Reproduction:: No Copyright.

View MARC record | catkey: 15426881