Ultrasound fuel flow sensing and control

An engine control system comprising:

• an electronic engine controller configured to operate at an update rate;
• a fuel flow measuring system operatively coupled to provide a fuel mass flow rate signal to the electronic engine controller, the fuel flow measuring system comprising
• a conduit through which fuel can flow,
• at least one fuel temperature sensor arranged to measure a fuel temperature associated with fuel flowing through the conduit,
• a first ultrasonic transducer and a second ultrasonic transducer arranged to direct ultrasonic signals through at least a portion of the conduit, the second ultrasonic transducer facing said first ultrasonic transducer, the first and second transducers operating at a transducer measurement interval, and
• a processor configured to calculate a mass flow rate of fuel through the conduit based at least in part on a first signal transit time for a first signal to travel from the first ultrasonic transducer to the second ultrasonic transducer, a second signal transit time for a second signal to travel from the second ultrasonic transducer to the first ultrasonic transducer, and the fuel temperature;
• wherein the transducer measurement interval is substantially the same as or shorter than the update rate the electronic engine controller.

A fuel flow sensor comprising:

• a conduit arranged to convey fuel therethrough, the conduit comprising, from upstream to downstream, a conduit inlet portion, a conduit center portion, and a conduit exit portion, the conduit center portion comprising a first end coupled to the conduit inlet portion and a second end coupled to the conduit exit portion;
• a first ultrasonic transducer disposed proximate the first end of the conduit center portion;
• and
• a second ultrasonic transducer disposed proximate the second end of said conduit center portion;
• wherein the conduit inlet portion and the conduit exit portion are substantially parallel and the conduit center portion is disposed at a non-zero angle with respect to the conduit inlet portion and the conduit exit portion.