Validation of Interface Capturing and Tracking techniques with different surface tension treatments against a Taylor bubble benchmark problem

•Quantitative validation of interfacial two-phase flow solvers.•Local 3D data of the shape of a rising Taylor bubble in a square milli-channel.•Benchmark for solvers with different approaches to surface tension calculation.•Detailed description of numerical methods used for surface tension calculation.•Quantitative discussion on uncertainties of experimental and numerical results. The validation and verification of models and numerical methods for interfacial two-phase flow simulation is still a challenge and standards have not yet been established. Mostly comparing with analytical solutions, many validation studies so far have considered simple or simplified two-phase flow scenarios. While this is mandatory for method development, complementary, validation against more complex test-cases is essential, in order to prove the method’s final scope of capabilities. However, one reason for the absence of such two-phase flow benchmark studies is the lack of freely accessible, detailed and high-quality experimental data. The Priority Program SPP 1506 Transport Processes at Fluidic Interfaces by the German Research Foundation DFG proposes a benchmark problem for validation of interfacial two-phase flow solvers by means of specifically designed experiments for Taylor Bubble Flow. The benchmark experiments aim at providing detailed and local data as a basis for validation. This contribution demonstrates its use by assessing and approving the reliability and accuracy of the solvers used by several research groups within the priority program. Special emphasis is set upon different approaches to surface tension calculation both for interface capturing and interface tracking methods. Data and material of the presented benchmark can be freely downloaded from the website of SPP 1506 (http://www.dfg-spp1506.de/taylor-bubble).