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NASA NTRS · 20180006153

In-Line Electromagnetic Actuator for Fuel Modulation

Okojie, Robert S.·Chang, Carl W.·Meredith, Roger D.·Thomas, Randy·Kopasakis, George
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Abstract

An in-line electromagnetic actuator with normally-open configuration has been developed for the purpose of exploring its application as a fuel modulator for the active control of combustor thermo-acoustic instabilities. The actuator is based on the spring-coil-plunger mechanism with the plunger designed to be suspended by crossed cantilever beam springs. Operational specification was set for a 1000 psi maximum inlet fuel pressure and modulation for a broad frequency bandwidth that encompasses frequencies that are typically associated with combustor thermo-acoustic instabilities. Various test results demonstrated fuel modulation up to 1200 Hz for coil excitation voltage between 2.3 and 4.6 V and current between 16 and 48 mA, respectively. The initial goal of this work was to demonstrate fuel modulation based on the concept of a normally-open fuel modulator with tethered plunger displacement.

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Okojie, Robert S., Chang, Carl W., Meredith, Roger D., Thomas, Randy, Kopasakis, George. 2018-07-09. In-Line Electromagnetic Actuator for Fuel Modulation. https://ntrs.nasa.gov/citations/20180006153

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