Sloshing reduction in microgravity with passive baffles: Design, performance, and supplemental thermocapillary control.

This article presents a detailed analysis of passive baffle designs for reducing fluid sloshing in microgravity, focusing on a rectangular container filled with a liquid similar to 5 cSt silicone oil. The study characterizes the sloshing response to pulse-like perturbations using metrics such as sloshing frequency (ω), decay time (τ_d), and damping ratio (ξ), and identifies the vertical centered baffle (1 × 8 mm²) as an optimal simple design achieving up to an 80% reduction in decay time. More complex baffle configurations—including cross-shaped and free surface baffles—are explored, showing enhanced sloshing mitigation by stagnating fluid and modifying flow patterns, though often at the cost of increased system complexity or reduced fluid volume. Additionally, the combination of passive baffles with active thermocapillary control, which manipulates surface tension via temperature gradients, is evaluated, demonstrating further improvements and suggesting a maximum achievable sloshing reduction of approximately 90%. The findings provide a comprehensive framework for designing fluid management systems in microgravity environments, with implications for space exploration technologies.