Cavitation Simulation using openFOAM

Kurzfassung

The Liquid Upperstage Demonstraotor Engine(LUMEN), is being developed by the Deutsches Zentrum f¨ur Luft- und Raumfahrt e.V. (DLR) at Lampoldshausen using the expander bleed cycle scheme. LUMEN will be set up as a modular breadboard engine that will serve as a testbed for component research at the engine level. Two turbopumps are currently being developed to supply propellant to the thrust chamber at adequate pressure levels. DLR will be able to further optimize the operating behavior of the pumps. So to have a firm grasp on the occurrence of cavitation. The implementation of a cavitation model including the thermal effect at cryogenic propulsion systems has been a challenging task. The objective of the current work to develop a cavitation model to simulate cavitating flow in liquid nitrogen. To do this, a two-dimensional quarter caliber hydrofoil is simulated with OpenFOAM following the experimental work done by Horn [32]. Extensive pressure and temperature investigations are taken into account to validate the Zwart cavitation model. The results show that the cavitation characteristic significantly differs from the isothermal condition when considering cryogenic environment. This work shows that the modified evaporation and condensation parameters play important factors for a better prediction of cavitation at experimental and respective empirical boundary conditions. The model showed that it is capable to model the quasy-steady cavitation over the hydrofoil more accurately. This thesis analyses proposed with two different approaches and comparison against experimental data. Differences are illustrated, and a decision is taken in turbopump construction that is suitable for the application.