On modeling and observer design of fluid flow dynamics for petroleum drilling operations

This paper presents a method for constructing an empirical simplified model of the fluid flow in the well during drilling operations. The model is fitted towards a snapshot of data generated by a detailed model. An observer is designed for the simplified model, utilizing the fast updated measurements at the surface, instead of slow updated and time-lagged downhole measurements. The observer is evaluated against the detailed fluid flow model. The results show that the designed observer is capable of following the detailed model sufficiently accurate.