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Riser System Digital Twin

Digital replicas of real-life riser systems aid operational decision-making for integrity management and life extension.

2H Offshore has undertaken a number of diverse initiatives to apply the digital twin concept in the field of riser engineering. We have developed and demonstrated proofs of concept for several applications and more recently have used this technology to deliver a specific solution to a client.

Simply put, a riser system digital twin is a digital replica of a physical riser system that is used as an operational decision-making tool for integrity management and life extension. Using a digital twin significantly reduces the time it takes to generate a health check of an in-service riser system. Where a conventional finite element analysis (FEA) approach may take a couple of months to derive stresses for one hot spot location using FEA simulations of a steel catenary riser based on three months of measured vessel motion, the same can be achieved in four hours using the digital twin approach.

How a Riser System Digital Twin Works

This machine learning approach initially uses the output from FEA or existing field data to train the digital twin of a representative riser configuration. The response of critical sections along the riser (target or output variables) is related to carefully selected feature (input) variables, which may include vessel motions and/or riser motions and curvatures. 2H has adopted recursive neural networks (RNN) and convolutional neural network (CNN) based algorithms to develop time domain stress and fatigue tracking in near real time. Read more about 2H’s machine learning applications for riser systems.

Development of a Digital Twin

To develop a digital twin, we work with clients to understand the field data already available. If needed, we can also help specify a vessel and riser monitoring system that will provide the input data to develop the digital twin for all of the risers and mooring lines on the asset. Whilst vessel motions are easily measured and more readily available, sometimes instrumenting one or two riser systems at key locations might be required to capture complex local response. The above approach is then used to assess the integrity of all riser and mooring systems tied back to the same host vessel, essentially acting as a virtual structural monitoring system. The digital twin can either be cloud based or deployed on-the-edge, providing a customisable and accessible user interface to process field data and visualise real-time stresses and fatigue damage accumulation in the riser over the life of field.