Abstract
Viscoelastic fluids such as dilute polymer solutions show anomalous drag reduction phenomena, for example, in a turbulent pipe flow. In order to investigate such phenomena quantitatively it is necessary to clarify the characteristic flow behaviour, especially the relationship between normal stress difference and shear rate. In this report, the method of measuring the total force acting on the outlet section of a pipe is adopted for obtaining a normal difference, and several problems affecting the relationship between normal stress differences and shear rate, such as flow disturbance, surface tension, and geometry of the exit, are discussed. From the results of measurements it is suggested that this method is applicable below certain values of the flow Reynolds number for very dilute polymer solutions of the order of 10 ppm concentration.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
