Accession Number:

AD0007128

Title:

Preliminary Evaluation of Turbine Performance with Variable-Area Turbine Nozzles in a Turbojet Engine

Descriptive Note:

Research memo.

Corporate Author:

NATIONAL AERONAUTICS AND SPACE ADMINISTRATION WASHINGTON DC

Personal Author(s):

Report Date:

1953-05-20

Pagination or Media Count:

40.0

Abstract:

The performance of a two-stage turbine with variable-area first - stage turbine nozzles was determined in the NACA Lewis altitude wind tunnel over a range of simulated altitudes from 15,000 to 44,000 feet and engine speeds from 50 to 100 percent of rated speed. The variable-area turbine nozzles were found to be mechanically reliable and to have negligible leakage losses. Increasing the turbine-nozzle-throat area from 1.15 to 1.67 square feet increased the corrected turbine gas flow or effective turbine nozzle area about 10 percent. At a given corrected turbine speed and turbine speed and turbine pressure ratio, changing the turbine nozzle area from 1.30 to 1.67 square feet lowered the efficiency 3 or 4 percent. The effect of increasing the turbine nozzle area from 1.15 to 1.67 square feet decreasing the turning angle about 7-12 deg would be to lower the turbine efficiency about 5 or 6 percent.

Subject Categories:

  • Jet and Gas Turbine Engines

Distribution Statement:

APPROVED FOR PUBLIC RELEASE