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Updated: Feb 20, 2026

Laboratory Drop Towers for the Experimental Simulation of Dust-aggregate Collisions in the Early Solar System
Published on: June 5, 2014
The measurement of the surface energy of solids using a laboratory drop tower
1Predevelopment, Product Division Dish Care, BSH Hausgeräte GmbH, Robert-Bosch-Straße 16, 89407 Dillingen an der Donau, Germany.
Abstract:
This work presents a technique for the study and measurement of the interfacial energies of solid-liquid-gas systems. The instrument and the evaluation method for the measurements obtained by it, allow the analysis of the energy changes of sessile drops submitted to microgravity. A mathematical model based on the thermodynamic of wetting is applied to evaluate the interfacial energies as a function of the drop shape changes due to the effect of the release of gravitation during the experiment. The presented model bases on the thermodynamic equilibrium of the interfaces and not on the balance of bi-dimensional tensors on the contour line. For this reason, the model does not follow Young's equation as the current surface wetting characterization techniques usually do.
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