A new method to determine the yield stress of a fluid from velocity profiles in a capillary

 

J.J. López-Durán, J. Pérez-González, B.M. Marín-Santibáñez and F. Rodríguez-González

 

 

  • The flow kinematics of a viscoplastic fluid in a capillary rheometer is described for the first time by using particle image velocimetry.

  • Evidence of true plug flow in a fluid is presented.

  • A reliable method to obtain the yield stress by using only the derivative of the velocity profiles and the capillary wall shear stress is presented.