Design Concept with Tip Leakage Vortex Control for Centrifugal Compressor Flow Stabilization

Positive feedback stabilization of centrifugal compressor surge

Stable operation of axial and centrifugal compressors is limited towards low mass 1ows due to the occurrence of surge. The stable operating region can be enlarged by active control. In this study, we use a control valve which is fully closed in the desired operating point and only opens to stabilize the system around this point. As a result, only nonnegative control values are allowed, which co...

Tip Leakage Flow Downstream of a Compressor Cascade with Moving End Wall

Aspects of Two-Phase Flow Screw Compressor Modelling Part I: Leakage Flow and Rotor Tip Friction

A one-dimensional leakage flow model for two-phase ammonia-water twin screw compressors is presented. The model takes into account viscous and acceleration forces and is based on three conservation equations and on the equation of state for homogenous NHiH20 mixture. The governing equations are solved with a finite difference method. Numerical shooting is used to find such inlet flow velocity a...

Effects of Different Turbulence Models in Simulation of Unsteady Tip Leakage Flow in Axial Compressor Rotor Blades Row

Characteristics of rotor blade tip clearance flow in axial compressors can significantly affect their performance and stable operation. It may also increase blade vibrations and cause detrimental noises. Therefore, this paper is contributed to investigate tip leakage flow in a low speed isolated axial compressor rotor blades row. Simulations are carried out on near-stall condition, which is val...

Centrifugal compressor surge and speed control

Previous work on stabilization of compressor surge is extended to include control of the angular velocity of the compressor. First a low-order centrifugal compressor model is presented where the states are mass flow, pressure rise, and rotational speed of the spool. Energy transfer considerations are used to develop a compressor characteristic. In order to stabilize equilibria to the left of th...