Rotating Detonation Engines

Rotating detonation engines (RDEs) are a promising technology for future propulsion and energy systems due to their high potential thermodynamic efficiencies and compact designs.

However, the development of these devices into robust, reliable systems requires continued experimentation. In the Hanson Research Group, we work with engine experts at the Naval Postgraduate School to support these experimentation efforts by developing laser sensors to measure H₂O, CO₂, CO, and temperature within their RDE combustors. The unique geometry of rotating detonation engine combustors led us to pioneer a single-ended sensor design, wherein laser light is both delivered and collected through the same window on the engine.

In combination with advanced diagnostic techniques that are able to overcome the intense vibration and thermal emission generated by the engine, our single-ended sensors provide crucial combustion data that will inform future rotating detonation engine designs.

a diagram showing different parts of a rotating detonation engine — A rotating detonation engine at the Naval Postgraduate School equipped with a single-ended laser sensor designed by the Hanson Research Group. The server rack (upper right) controls the lasers (lower right), which are connected to a fiber optic cable (center). Light from the fiber is delivered to and collected from the engine (lower left) by the detection assembly (upper left). Figure adapted from [4].

To learn more, check out some of our publications:

[1] Peng, W. Y., Goldenstein, C. S., Spearrin, R. M., Jeffries, J. B., Hanson, R. K., “Single-ended mid-infrared laser-absorption sensor for simultaneous in situ measurements of H₂O, CO₂, CO, and temperature in combustion flows,” Applied Optics, Vol. 55, No. 33 (2016) pp. 9347–9359. DOI: 10.1364/ao.55.009347

[2] Peng, W. Y., Cassady, S. J., Strand, C. L., Goldenstein, C. S., Spearrin, R. M., Brophy, C. M., Jeffries, J. B., Hanson, R. K., “Single-ended mid-infrared laser-absorption sensor for time-resolved measurements of water concentration and temperature within the annulus of a rotating detonation engine,” Proceedings of the Combustion Institute, Vol. 37, No. 2 (2019) pp. 1435–1443. DOI: 10.1016/j.proci.2018.05.021

[3] Cassady, S. J., Peng, W. Y., Strand, C. L., Dausen, D. F., Codoni, J. R., Brophy, C. M., Hanson, R. K., “Time-resolved, single-ended laser absorption thermometry and speciation in a H₂/C₂H₄-fueled rotating detonation engine,” Proceedings of the Combustion Institute, Vol. 38, No. 1 (2021) pp. 1719–1727. DOI: 10.1016/j.proci.2020.06.125

[4] Peng, W. Y., “Single-ended laser-based diagnostics for thermometry and speciation in detonation-driven combustors,” Ph.D. Thesis, Stanford University (2019)