Numerical investigation of field-scale geysers in a vertical shaft

Geysers in dropshafts of stormsewer systems are consecutive eruptions of a mixture of gas and liquid that can attain heights of more than 30 m. The present study investigates the mechanisms and characteristics of these extreme events numerically using OpenFOAM toolbox. The numerical model is based on a compressible two-phase flow solver and was validated using laboratory tests that achieved large eruption heights. The results show that the aforementioned experimental geysers can be reasonably well simulated using two- and three-dimensional numerical models. Further studies are needed to verify the applicability of two-dimensional models for simulating geysers in actual stormsewer systems. Moreover, the results suggest that compressibility of air plays a critical role in the formation of geysers. Overall, the conducted numerical study provides insights into the characteristics of geyser eruptions and presents some criteria for performing efficient numerical simulations of these events.