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This paper investigates the performance of a double actuator electronic fuel control unit, when installed on a gas turbine engine. The validated mathematical model of the unit is linked to a quasi-linear engine mathematical model. A combination of two operating modes of the unit is used to improve the fuel delivery characteristics. Acceleration and maximum speed governing of the engine are simulated. Two control strategies are investigated. In the first, the fuel flow rate and the engine speed are used as feedback signals. In the second, the N-Dot control, which eliminates the need for fuel flow feedback during engine acceleration, is studied.

The potential benefits of digital electronic controls, including increased flexibility and lower cost, have not yet been fully applied to the small gas turbine engines of remotely piloted vehicles. For these applications, the need for low cost is a strong factor in design. To address this situation, a new, simple and inexpensive electronically controlled metering system for small gas turbine engines is proposed. The system incorporates a diaphragm type valve keeping a constant differential pressure across a stepper motor actuated metering valve. To optimize the design, mathematical models were created for computer simulation. Experimental tests performed on a prototype showed that it can adequately meet the fuel schedules of small gas turbines. The simulation models were validated against the test results and were used in design optimization.

A new family of low cost electronic fuel control units is being proposed for small gas turbine engines of remotely piloted vehicles and auxiliary power units. It has a modular design incorporating an electronically actuated metering valve which can be matched with various types of differential pressure valves controlling the pressure drop across the metering valve. Four different configurations are proposed: metering valve only, metering valve with diaphragm type differential pressure valve, metering valve with bypass valve and double valve configuration, the latter with a back-up capability. These configurations can satisfy various demands from gas turbine engine producers. Some components of automotive fuel injection system could be used to reduce the cost of these units as well as components from the DP-F2 fuel control which has been in production for a long time. This adds to the confidence of the reliability and durability of this new design.

The Montreal area has a well developed aerospace industry with a continuous need for young engineers broadly educated in aircraft propulsion. To fulfil this requirement, three Montreal universities: Concordia University, École Polytechnique, and McGill University, with the cooperation of interested industrial enterprises, launched a joint Master of Engineering (Aerospace) program. It included several courses directly related to aircraft propulsion such as: Advanced Turbomachinery and Propulsion, Gas Turbine Design, Fuel Control Systems for Combustion Engines, Vibration Problems in Rotating Machinery, etc. They were supported by prerequisite basic courses. Some of these courses have also been made as electives to these undergraduate students in Mechanical Engineering Program who want to specialise in Aeronautics. The paper gives a more detailed description of courses and laboratories from the point of view of aircraft propulsion teaching.