Unique approach optimizes electroaerodynamic propulsion

Imagine stripping electrons from the surrounding air and accelerating the resulting charged molecules—or ions—to produce the thrust necessary for air travel. This scenario sounds like science fiction, but electroaerodynamic (EAD) propulsion is on the cusp of becoming science fact.

Unlike conventional propulsion systems that use propellers or gas turbines, EAD is quieter, mechanically simple and does not emit combustion emissions. Current EAD designs use direct current corona discharge to produce and accelerate ions, but the trade off between thrust-to-power and thrust density limits its application.

“Theoretically, ion wind is efficient, but in practice, it is not,” said the study’s co-author Steven Barrett. “This new approach is getting us closer to the theoretical maximum for ion wind generation. It’s quite exciting.”

In their study, Xu et al. decoupled ion production and acceleration. They used dielectric barrier discharge to produce ions and DC field to accelerate the ions in the system. This step improved the ion wind generation efficiency, potentially removing a barrier for the practical adoption of this technology.

The resulting propulsion is twice the equivalent of previous systems with a lower power draw (thrust-to-power value: 10 to 20 N/kW and thrust: 50 to 150 mN/m). The team notes that the power draw is balanced by the improvements in the thrust-to-power component.

Barrett and his colleagues aim to examine the efficiency of the system in future test flights. They are also interested in integrating this approach into the surface of an aircraft, creating a propulsive skin.

Source: “A dielectric barrier discharge ion source increases thrust and efficiency of electroaerodynamic propulsion,” by Haofeng Xu, Yiou He, Steven R. H. Barrett, Applied Physics Letters (2019). The article can be accessed at https://doi.org/10.1063/1.5100524 .