Naval Air Propulsion Center (NAPC) personnel have implemented a hardware-in-the-loop simulation for the purpose of evaluating engine fuel system components. The objective was to establish a closed-loop test capability that would be cost-effective, easy to use and versatile. The approach uses a hybrid computer with the digital portion providing the data acquisition and display capability and the analog portion providing dynamic engine simulation. The main fuel control metered flow is used as the model driving parameter.
An alternative to conventional testing is available through closed-loop testing using the hybrid computer system. The benefits to be gained include the generation of more realistic data (directly relatable to on-engine operation, a powerful trouble-shooting tool and easily automated endurance testing which provides compatibility with advanced hydromechanical and electronic fuel controls.