An International Effort to Compare Gas Hydrate Reservoir Simulators

This collaborative effort to compare the world’s leading gas hydrate reservoir simulators is designed primarily to exchange information and insight that will lead to the improvement in simulation capability of experimental and naturally occurring gas hydrate accumulations. The initial phase of the code comparison activity achieved the simulation of five problems of increasing complexity by five different reservoir simulators: CMG STARS, HydrateResSim, MH21 HYDRES, STOMP-HYD, and TOUGH+HYDRATE. The cases run, the results obtained, and an analysis of those results is available to the gas hydrates community through the DOE/NETL website[1]. Results of the Problem 1 (non-isothermal multi-fluid transition to equilibrium (no hydrate); and Problem 2 (closed-domain gas hydrate dissociation) indicated very close agreement among the simulators. This agreement suggests that all had consistently captured the basics of mass and heat transfer, as well as overall process of gas hydrate dissociation. Problem 3 (dissociation in a onedimensional domain), which included several scenarios, one in which ice formation was likely, produced the initial divergence among the simulators. Other differences were noted in both Problem 4 (gas hydrate dissociation in a one-dimensional radial domain) and Problem 5 (gas hydrate dissociation in a two-dimensional radial domain), resulting in significant corrections to algorithms within several of the simulators. Given the lack of real world data for validation purposes, these improvements would likely not have been identified without the comparison activity. This paper will outline the nature of the first five cases studies of the code comparison effort and their results.