PULSE WIDTH MODULATED FUEL METERING SYSTEM

摘要

PULSE WITH MODULATED FUEL METERING SYSTEM A fuel metering system for a gas turbine engine with a low pressure drop fuel vaporizing system includes an engine driven centrifugal pump (10) supplied with fuel at a given absolute pressure (Pi) from a tank The pump discharges fuel to a rapidly pulsed, solenoid operated ball valve (20) which functions as a metering valve in controlling flow to the engine. The solenoid (38) of the metering valve receives periodic voltage pulses of appropriate width from an electronic control which senses selected engine parameters and computes the required fuel flow and the pressure differential (Pr-PD) across the metering valve. Since the pressure differential across the metering valve increases with engine speed, favorable flow turndown ratios may be achieved without operating the metering valve at high or low values of duty cycle.