Ultrasound-assisted germination (UAG) has emerged as a process intensification strategy to enhance seed performance while improving resource efficiency. In this study, a multiphysics framework combining thermoacoustic modeling with experimental validation was developed to investigate resonance-driven UAG in Cucurbita pepo. Frequency-domain analysis identified 40 kHz as the resonance condition of the seed–fluid system, enabling spatial localization of acoustic energy. Simulations showed that temperature remained below 46 ∘C across all exposure times, excluding bulk thermal effects and supporting a predominantly mechanical activation mechanism. Experimental treatments (40 kHz, 1.5 MPa, 5–25 min) revealed a non-linear germination response. The optimal condition (10 min) increased final germination from ∼20% to 46.8% and reduced the time to steady state from 13 to 10 days. Statistical analysis confirmed significant improvements for treatments between 10 and 25 min (p<0.001), while 5 min showed no effect. Longer exposures did not produce proportional gains, indicating a finite acoustic energy window. Because daily water (0.45 L·day−1) and electrical (0.438 kWh·day−1) consumption remained constant, shorter process duration reduced cumulative resource demand. The optimal treatment decreased water use by 1.35 L (23.1%) and energy consumption by 1.29 kWh (22.7%). When normalized per germination output, energy and water requirements decreased by ∼67%. These results demonstrate that integrating resonance-based multiphysics modeling with experimental validation enables rational optimization of UAG, providing a scalable and resource-efficient strategy for controlled-environment agricultural systems.
Aguilar-Torres et al. (Sat,) studied this question.