LES Analysis of a Rocket Turbopump Inducer in Non-Cavitating and Cavitating Flows

A large eddy simulation (LES) of a rocket turbopump inducer in non-cavitating and cavitating flows is presented. The computation takes full account of the interaction between the rotating inducer and the stationary casing by using a multi-frame-of-reference dynamic overset grid approach. A streamline-upwind finite element formulation with second-order accuracy both in time and space is used to discretize the governing equation. It is implemented in parallel by a domain-decomposition-programming model. The evolution of cavitation is represented by the source/sink of vapor phase in the incompressible liquid flow. The pressure-velocity coupling is based on the fractional-step method for incompressible fluid flows, in which the compressibility is taken into account through the low Mach number assumption. The internal flow of an inducer is simulated and compared with water tunnel experiments at the design (φ = 0.078) and off-design conditions (φ = 0.05 and 0.09) in non-cavitating flows. The overall head-flow characteristics of computed results show good agreement with experiments. Such results show that the applied LES code can be used as a design tool for rocket turbopump inducers.