A method and a metering valve for metering a fluid by incrementally adjusting a position of a flow control element that directly varies a flow area of a flow port opening in a valve housing. The flow control element is adjustably mounted with respect to the valve housing. The metering valve maintains an approximately constant percentage variation of a mass flow rate of a fluid with respect to the current total flow rate flowing through the flow port opening, for each incremental adjustment of the flow control element position, throughout the metering range of the metering valve yielding an exponentially varying mass flow rate as a result of linearly varying the flow control element position.
Steven R. King; James J. Cole; Kennon H. Guglielmo; John P. Latusek