Comparison of steady state results from five different thermohydraulic simulators using strictly identical input data

摘要

Numerous thermohydraulic simulators are available on the market for steady state calculations. Even though several of them have been validated against experimental as well as field data, they often seem to give different results when modelling identical systems. The problem is thereafter to define which results are most reliable? The use of different steady state flow correlations and different ways to present fluid PVT data tend to make such comparisons even more complicated. Based on these realities, a steady state comparison programme was launched to answer the question: "Will all results be equal if every simulator was exposed to identical input data in every sense of the word?" A hypothetical subsea production system was developed to define a very challenging transport system giving no room for tuning. The system was described in every detail in a rigorous design basis, including specifications of steady state correlation and fluid data. Four commercial suppliers of multiphase flow simulators were asked to perform thermohydraulic calculations of this system. In addition, Hydro decided to perform the same calculations with our in-house process simulator. The comparison programme proved to be a powerful tool to identify software bugs included within the software, since it was possible to give very detailed feedback to every supplier.