An experimental and theoretical approach on real-time control and monitoring of the apparent viscosity by fuzzy-based control

This paper aimed to develop a real-time monitoring and Fuzzy-based control system for non-Newtonian fluids properties as apparent viscosity. Fuzzy logic was chosen as the control paradigm due to its low implementation complexity compared to other advanced control techniques and its outstanding feature of simplifying the transfer of knowledge from the operator/expert to the control system. To validate the proposed fuzzy control strategy, the authors developed a flow loop system for real-time monitoring and controlling the viscosity of carboxymethylcellulose's aqueous solutions. For apparent viscosity monitoring, a tubular viscometer was developed based on volumetric fluid flow and pressure drop in a defined tube length. The control strategy used in this work was based on Fuzzy Logic, with the Mamdani inference method, which was based on the possibility of transferring the linguistic information from the expert process operator's knowledge to the machine domain language, thus establishing the knowledge basis of the fuzzy controller. The proposed control strategy was validated by experimental tests in a flow loop system, regulator, and servo problems for apparent viscosity. Results showed the Fuzzy controller's satisfactory performance, which proved to be a great potential tool for online monitoring, preparation, and control of the apparent viscosity of drilling fluids.