| 摘要 |
A fuel management system (34) for a turbine engine having a metering valve (50) controlled by the input of an electronic computer (36) to a resolver (48). A head pressure sensor (67) responds to pressure differential across the fuel metering valve (50) to control a bypass valve (80) which allows a portion of the fuel available from a fuel supply conduit (58) to return to a fuel reservoir (28). A reference pressure controlled head bypass valve (80) utilizing pressures above (P1) and below (P2) a metering valve (50) as reference pressures during normal operation and a non-controlled reference pressure during shut-off to maintain a minimum fuel pressure required for control purposes during shut-off. The non-controlled pressure reference may be obtained as a pressure drop across a series (typically a pair) of small orifices or apertures. The non-controlled reference pressure is typically achieved as the intermediate pressure between a regulated (pcb) body pressure and the inlet fuel supply pressure (P1).
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