Drilling Modeling and Simulation: Current State and Future Goals

Abstract

This article, written by Special Publications Editor Adam Wilson, contains highlights of paper SPE 173045, “Drilling Modeling and Simulation: Current State and Future Goals,” by Junichi Sugiura, SPE, Schlumberger; Robello Samuel, SPE, Halliburton; Joachim Oppelt, SPE, Baker Hughes; G.P. Ostermeyer, SPE, Braunschweig Technical University; John Hedengren, SPE, Brigham Young University; and Paul Pastusek, SPE, ExxonMobil, prepared for the 2015 SPE/IADC Drilling Conference and Exhibition, London, 17–19 March. The paper has not been peer reviewed. The process of drilling a borehole is very complex, involving surface and downhole drilling systems that interact with the drilling fluid and the surrounding rocks. Modeling and simulating every aspect of the drilling process and drilling system is still considered too complex to be realized. However, many areas of modeling and simulation are undergoing aggressive development, and the advancement of this technology may dramatically improve future attempts to model and simulate the entire drilling process accurately. Introduction Drilling modeling and simulation (DMS) involves modeling and simulating the behavior of drilling systems or processes. DMS should provide crucial information about drilling systems or processes without actually constructing a well. DMS methods are designed to help enhance drilling efficiency, productivity, and performance; manage various risks effectively; and consequently improve personal safety. Recently, many DMS software applications have come to be used in the predrilling stage as well as in real time. In an operations phase, models are returned and rerun to obtain the best predictions of drilling systems. Drillstring-Dynamics Models A recent review of the current progress and future needs for drillstring dynamics suggested that new monitoring and control solutions may be enabled by the adoption of wired drillpipe by offering high-speed telemetry up to 500 kbit/sec or high-frequency data logging up to 1400 Hz. Future work that remains for drillstring dynamics is development of coupled vibration models, validation of existing models with laboratory and rig data, model-based automation solutions, and improved predictions of damage from severe vibration, whirl, and bump events. Recently, it has become feasible to model the dynamic behavior of a drillstring in great detail (Fig. 1) and be fairly confident that the resulting motion is representative if all the input parameters for the model (e.g., interfacial relationship between drillstring, rock, and fluid) are known precisely. In practice, one can only know these parameters to within certain bounds. Within these bounds, a wide range of behaviors is possible, from benign to possibly catastrophic, depending on the design of the drillstring. Consequently, all predictions boil down to a comprehensive parameter-sensitivity analysis.