The Effects of Compressibility on the Upwash at the Propeller Planes of a Four Engine Tractor Airplane Configuration Having a Wing with 40 deg of Sweepback and an Aspect Ratio of 10
Abstract
An investigation has been conducted in which upflow angles were measured along the horizontal center lines of the propeller planes of a semi span model representing a multiengine airplane with tractor propellers. The wing had 40 deg of sweepback, an aspect ratio of 10, and a taper ratio of 0.4. Tests were conducted at Reynolds numbers of 2, 4, 6, and 8 million at low Mach numbers, and a Reynolds number of 2 million at Mach numbers from 0.25 to 0.92. In addition, the upflow was measured with the nacelle alone to evaluate the theoretical method for predicting the upwash induced by the nacelle. The tests with the nacelle alone were conducted at a Reynolds number of 4 million at a Mach number of 0.123, and at a Reynolds number of 2 million at Mach numbers from 0.60 to 0.92. The results indicate that for Mach numbers up to 0.60 the upwash angles can be predicted accurately by the available theoretical methods. At Mach numbers above 0.60 the experimental values were less than those predicted by theory and this difference increased with increasing Mach number.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1956
- Accession Number
- ADA377335
Entities
People
- Armando E. Lopez
- Jerald K. Dickson
Organizations
- National Aeronautics and Space Administration