A research team led by Professor Steven Wang , Associate Vice-President (Resources Planning) and Associate Professor in the Department of Mechanical Engineering and School of Energy and Environment, has designed a revolutionary capillary structure that can trigger the Leidenfrost effect, offering a practical solution for the temperature-regulated Leidenfrost effect without requiring complex surface engineering.
The study, titled “ Capillary Leidenfrost Effect ”, was recently published in the prestigious international journal Nature Physics .
The Leidenfrost effect is a physical phenomenon discovered in 1756. It occurs when a liquid droplet touches a surface much hotter than its boiling point, forming a vapour layer that makes it levitate and hover, slowing down evaporation. A simple example is water on a very hot pan: the drops sizzle and disappear quickly, but once it reaches the Leidenfrost point, they bead up, skate and dance around on a steam barrier, and last much longer before evaporating. This effect is ubiquitous in a wide range of laboratory and industrial applications.
Since a thermal insulating vapour layer is formed by the Leidenfrost effect, heat transfer performance is significantly reduced, and there is a risk to make the liquid cooling of high-temperature surface ineffective. As a result, since its discovery more than 200 years ago, the Leidenfrost effect has been extensively and intensively studied. However, it remains extremely challenging to control the conventional effect due to the complex liquid dynamics.
The research team has uncovered a new Leidenfrost behaviour, the Capillary Leidenfrost Effect, providing a stable and sustainable solid levitation by liquid evaporation at a temperature threshold of only 110 ℃, significantly below the Leidenfrost point of its droplet counterpart, yet without the need for specialised surface manufacturing techniques.
The study has revealed the lowest Leidenfrost Point (LFP) reported to date, yet without relying on any specialised surface manufacturing techniques, which is contrary to the existing studies that the Leidenfrost effect requires a substrate temperature significantly higher than its boiling point. In contrast, upon liquid infusion, the capillary structure immediately transitions to the Leidenfrost regime. This levitation state is maintained for approximately two minutes; however, it can be sustained indefinitely through continuous liquid replenishment.
The ultra-low LFP could remarkably reduce the critical heat flux required for initiating the Leidenfrost effect by 5.6 times compared with that on a common metallic surface. More importantly, it could significantly save the energy input for frictionless motion applications, providing a new way to sustain stable Leidenfrost heat flux.
“By confining liquid within capillaries, we can achieve precise control over the LFP,” Professor Wang said. “Conventionally, the mode of liquid phase change is passively dictated by temperature, but now we demonstrate the ability to customise the LFP using structural parameters based on our practical needs.”
He emphasised that two possible future applications of this new discovery are advanced heat management and scalable frictionless motion.
“We can control the temperature at which boiling regimes shift, maintaining highly efficient cooling over a much broader range of operating conditions, thus revolutionising the design of heat exchangers and cooling systems for high-performance electronics and power generation,” he said.
The study will help shape a new era for industrial applications, as the effect has been proven robust and achievable using a wide range of inexpensive materials. Frictionless motion and drag reduction on an industrial scale hold huge potential for applications such as contactless transportation systems and ultra-low-friction bearings.
Nature Physics
Capillary Leidenfrost effect
14-Apr-2026