DETERMINATION OF OPTIMIZED PROPELLERS FOR GROUND EFFECT MACHINES
Abstract
A theoretical analysis of the performance of a propeller-duct combination operating in ground effect was extended from the work conducted under Contract DA 44-177-TC-524, which was reported in Reference 1. A propeller was designed for optimum twist and taper and to pro vide a constant velocity across the GEM nozzle, thus producing a maximum lift-to-power ratio of the GEM in accordance with this reference. The optimum propeller design was of the same propeller solidity as a rectangular, non twisted blade propeller tested previously to obtain a direct comparison of performance. The method of analysis used to determine the performance, loads, and moments produced on a blade of arbitrary planform and twist operating in a duct is presented. A test program was conducted to determine the effect of the optimized propeller on GEM performance. The duct nozzle area was also varied to determine the effect of this parameter on propeller optimization. Propeller blade stall, along with large inlet losses which occurred during certain operating test conditions, resulted in performance which could not be accounted for in the analysis.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1963
- Accession Number
- AD0414989
Entities
People
- N. J. Miller
- N. M. George
- R. R. Pruyn