Wet Gas Compressor Modeling and Performance Scaling

Abstract

Today, a few subsea compressor systems are already operating while several new installations are expected within the next years. This creates a need for dynamic simulation tools to ensure proper system design and to facilitate production. The well-known process simulator Hysys Dynamics has been extended to include wet gas compressors, which includes the possibility for the user to input multiple performance curves based on the inlet gas/liquid content. The current paper analyzes the accuracy of the compressor performance procedure within the simulation model when operating with multiple wet performance curves. The findings have been validated against both air/water and hydrocarbon performance data. Further, the affinity laws have extensively been used by the industry and within process simulation tools for performance scaling. Experimental data from the wet gas compressor test facility at the Norwegian University of Science and Technology (NTNU) have been used to validate the applicability of the affinity laws in wet gas flow. The test facility is an open loop configuration consisting of a single shrouded centrifugal impeller, a vaneless diffuser and a circular volute. The test reveals that the compressor performance procedure within the model provides accurate results in both air/water and hydrocarbon flow. Further, for the given application the affinity laws yield a satisfactory estimation in wet gas flow.