Heat exchanger

摘要

A gas turbine engine has a fan, a compressor section, a combustor, and a turbine section. The fan delivers a portion of air into the compressor, and into a duct, as bypass air. A bleed air system bleeds a quantity of air from the compressor into a chamber at least at low power conditions of the engine. The bleed air system has an opening which may be selectively closed to block bleed air, or opened to allow bleed flow from the compressor into the chamber. A heat exchanger is positioned such that a first surface of the heat exchanger is contacted by bypass air in the duct, and a second surface of the heat exchanger is contacted by bleed air when the bleed air system directs air from the compressor into the chamber.

主权项

1. A gas turbine engine comprising:
a fan, a compressor section, a combustor, and a turbine section, said fan delivering a portion of air into said compressor, and said fan delivering a portion of air into a duct, as bypass air; a bleed air system for bleeding a quantity of air from the compressor into a chamber at least low power conditions of the gas turbine engine, said bleed air system having an opening which may be selectively closed to block bleed air, or opened to allow bleed air from the compressor to the chamber; a heat exchanger having fluid containing passages to be cooled and a heat exchanger wall, said heat exchanger positioned such that a radially outer surface of said heat exchanger wall is contacted by bypass air in the duct, and a radially inner surface of said heat exchanger wall is contacted by bleed air when said bleed air system is directing air from the compressor into the chamber, wherein said heat exchanger wall separates the bypass air from the bleed air; and said heat exchanger fluid containing passages communicating with a lubricating fluid from an accessory on said gas turbine engine.