Solid-State Marine Propulsion via Resonant Ionic Momentum Transfer (RIMT)

Modern marine propulsion remains dependent on mechanical screw propellers, a paradigm constrained by cavitation, turbulent vortex shedding, and fundamental momentum-theorem efficiency limits. This paper proposes and analyses Resonant Ionic Momentum Transfer (RIMT), a solid-state propulsion mechanism that converts the entire wetted hull surface of a vessel into a distributed electrokinetic engine. RIMT applies a MHz-frequency asymmetric traveling-wave potential via a sub-surface interdigitated electrode lattice, manipulating the Electrical Double Layer (EDL) of seawater to generate directed ionic flow through electro-osmotic coupling. Operation in the Faradaic-suppression band (2–5 MHz, where the per-half-cycle Faradaic charge falls below the water-splitting threshold) prevents electrolytic degradation, enabling efficient momentum injection without chemical loss. A modular 30 cm × 30 cm Active Tile architecture, driven by GaN wide-bandgap power electronics, provides fault tolerance, scalability, and adaptive frequency control. First-order computational models validate the mechanism: the Péclet number at the hull–fluid interface is Pe ≈ 65, confirming that electric-field-driven ion transport dominates Brownian diffusion by nearly two orders of magnitude. Efficiency analysis under the asymmetric sawtooth waveform shows that an un-tuned configuration (1 µm Al₂O₃ dielectric, 200 V fixed drive) is dominated by displacement-current ohmic heating and achieves only η ≈ 3 %, demonstrating that adaptive voltage control is essential. An optimised design (500 nm Ta₂O₅ ALD dielectric, analytically tuned 5.3 V drive) reaches η ≈ 83 % (first-order upper bound; experimental validation pending), exceeding the practical efficiency ceiling of mechanical propulsion (~70–72 %) by approximately ten percentage points. By publishing this architecture as a prior-art disclosure under CC BY-SA 4.0, we establish open prior art and invite experimental validation by the global research community.