Multi-parameter control for centrifugal compressor performance optimization

Abstract

The potential performance benefit of actuating inlet guide vane (IGV) angle, variable diffuser vane (VDV) angle and impeller speed to implement a multi-parameter control on a centrifugal compressor system is assessed. The assessment consists of first developing a one-dimensional meanline model for estimating performance of centrifugal compressor system followed by the formulation of a control framework incorporating the meanline model. Performance estimate of a representative centrifugal compressor system with adjustable IGV angle, VDV angle and impeller speed using the meanline model is in accord with available test data. The impeller performance estimate based on the meanline model is also in accord with computed results from Reynolds Average Navier-Stokes Equations. The simple control framework can be used to optimize on the fly the compressor operation to meet a specific mission requirement by selecting an appropriate combination of impeller speed, IGV and VDV angle settings. Desirable flow configurations with the required performance in response to specified operating needs have been obtained to serve as illustrations on the practical utility of the control framework. Results provide guidelines and attributes of compressor for achieving the required performance and operation at the system level through prioritizing the actuation of the adjustable parameters; for instance impeller speed would provide a high level of leverage to affect the compressor performance on an effective basis and that the IGV angle should be confined to a specified range. While the results have not been assessed in an experimental setting, they are used to design and plan an experimental program for evaluating the proposed simple multi-parameter control strategy. Flexibility have been incorporated into the formulation to allow the refinement and updating of the model for improved accuracy and fidelity.