BYPASS DUCT HEAT EXCHANGER WITH CONTROLLED FAN

摘要

A gas turbine engine comprises a main fan (99) that delivers air into a bypass duct and into a core engine. A heat exchanger (104) is positioned within the bypass duct and receives a fluid to be cooled from a component associated with the gas turbine engine. A heat exchanger fan (116) is positioned to draw air across the heat exchanger and a control for the heat exchanger fan. The control is programmed to stop operation of the fan during certain conditions, and to drive the heat exchanger fan under other conditions. A method of forming a heat exchanger is also disclosed.