Correction model research on oil well downhole flowrate test based on venturi

Permanent downhole flowrate test is a key technology for refined oil field development. A venturi flowrate correction model based on system identification technology was put forward to improve downhole flowrate test accuracy. Firstly, conventional venturi theoretical model and effect factors were analyzed, then building the correction model with the factors flowrate coefficient and differential pressure, combined with downhole flow condition. Finally, experiment platform was used to verify the correction model. The results indicated that flowrate test accuracy based on the correction model can be controlled within 5% between 13.8-37.1 m³/d comparing with the conventional flowrate test accuracy 16.2%. So the venturi flowrate test correction model based on system identification can improve oil well downhole flowrate test accuracy and provide technical support for oil field development.