Development of a Transient Fluid Dynamic Solver for Compression System Pulsation Analysis
The Southwest Research Institute (SwRI) IPPS code has been successfully used in pulsation analysis for slow-speed compression system design for the last ten years and more recently in the design of the new high-horsepower, high-speed compressor installations. The IPPS solver utilizes a solution algorithm of the transient acoustic wave equation in the frequency domain, which has been demonstrated to provide highly accurate results for compression system resonance frequencies and good agreement for pulsation amplitudes. However, the mathematical assumptions associated with solving the acoustic wave equations must lead to discrepancies in amplitude predictions as these equations are only a partial physical model of the actual transient fluid dynamics. A full one-dimensional representation of the governing transient fluid dynamic equations (called the Navier-Stokes equations) can provide a more thorough solution for the pulsating flow field and can provide more accurate pulsation amplitude predictions. This is particularly critical in the design of variable high-speed compressor systems, as for these applications complete resonance avoidance is impossible. Thus, SwRI decided to developa new one-dimensional time-domain Navier-Stokes model to improve SwRIs prediction capabilities for transient compressor station manifold and piping systems. The resulting state-of-the-art piping pulsation analysis tool (called TPS) will lead to better design optimization capabilities for the pipeline industry. This paper describes the TPS solver development and validation testing.