Quasi-Steady Heat Flux Characterisation of 3D Printed Cylindrical Holed Wicks Using a Continuous Optical Method

Evaporation rates from wick structures are commonly measured using gravimetric techniques. In this study, we propose a novel continuous optical method to quantify the evaporation rate from wick structures. This method is used to measure the quasi-steady evaporation heat flux and determine the cooling performance of six 3D-printed wick structures with different surface geometries with no external heat. A diffusion model based on the surface temperature is used to assess the measured heat fluxes against a theoretical reference and provide insights into the underlying heat and mass transfer processes. The combined experimental–numerical framework demonstrates a route to robust, high‑resolution characterisation of evaporation performance in additively manufactured wick structures, supporting future geometry optimisation for high‑heat‑flux thermal management applications.