Accession Number:

ADA443338

Title:

Inlet Flow-Field Measurements of a Transonic Compressor Rotor Prior to and During Steam-Induced Rotating Stall

Descriptive Note:

Master's thesis

Corporate Author:

NAVAL POSTGRADUATE SCHOOL MONTEREY CA

Personal Author(s):

Report Date:

2005-12-01

Pagination or Media Count:

87.0

Abstract:

Steam leakage from an aircraft carrier catapult is sometimes ingested by the aircrafts engines upon launch which may induce compressor stall. Investigation of the phenomenon known as a pop stall is of particular importance as the Navy prepares to field the F35C, the aircraft carrier variant of the joint strike fighter. The single engine design of the F-35C makes this aircraft particularly susceptible to steam-induced stall during catapult launch. The present project examined compressor stall and included steady-state as well as transient measurements in the inlet of a transonic compressor prior to and during a steam-induced stall. Hotwire measurements of the inlet flow field were taken to determine an inlet turbulence intensity of 2-3 during both subsonic as well as transonic compressor operation. A 95 speed line was established from data taken from open throttle to near stall. Hot-film and Kulite pressure data taken near stall showed the existence of a stall precursor which appeared near half rotor speed. Steam was injected into the inlet however the initial method added mass to the system and did not induce a stall. A decrease in the amplitude of the pressure trace was observed however. A stall was induced by steam ingestion ahead of the existing inlet throttle, with upstream transient measurements taken using both hot-film and Kulite pressure transducers.

Subject Categories:

  • Hydraulic and Pneumatic Equipment
  • Fluid Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE