First implementation of a novel low-temperature-driven motionless pump

Knudsen pumps (KP) are temperature-gradient-driven devices devoid of moving parts, possessing significant potential for applications such as vacuum generation, fluid delivery, and gas separation. To the best of our knowledge, there remains a gap in the study of low-temperature-driven Knudsen pumps (LT-KP), as highlighted in recent research. In this work, we present the first simulation, design, and implementation of a novel LT-KP operating across a broad cryogenic-to-ambient range. The LT-KP achieved unprecedented performance by combining the principles of thermal transpiration and dimensional analysis with insights from recent Knudsen theoretical and experimental models. The LT-KP exhibits notable pressure generation performance and unique gas flow characteristics over a temperature range from liquid nitrogen to room temperature (77–300 K). Within this system, a parametric study was conducted to investigate the effects of temperature gradients and gas rarefaction on the pressure generation and flow rate performance of the proposed LT-KP. Insights were gained from the LT-KP's performance across various gases (helium, nitrogen, and argon). This work establishes the experimental groundwork and proposes design guidelines aimed at advancing the development of next-generation gas transport and refrigeration technologies, with a focus on energy efficiency and reliability. These innovations are poised to have significant applications in space exploration and the hydrogen economy, as well as in industrial processes and environmental sustainability.