Extensional and torsional pipe flow
نویسندگان
چکیده
منابع مشابه
Coupled extensional and torsional deformations of a piezoelectric cylinder
We derive a one-dimensional model from the three-dimensional equations to analyze electromechanical deformations of a piezoceramic cylinder. We show that its extensional and torsional deformations are coupled if the axis of polarization at a point makes a nonzero angle with the axis of the cylinder and the projection of the polarization vector on a cross section is perpendicular to the radial l...
متن کاملExtensional Flow of Bulk Polymers
A standard Instron testing machine, in which crosshead displacement varies linearly with time was modified so that crosshead displacement varies exponentially with time. This change permits testing at constant Hencky strain rate (c = fi/8), which provides a constant stretch history for both simple extensional flow and strip biaxial extensional flow. This results in a visualization of the steady...
متن کاملManipulating Flow Structures in Turbulent Pipe Flow
Two different tools, the non-empirical resolvent analysis and the data-based dynamic mode decomposition, are employed to assess the changes induced by transpiration in the dynamics of a turbulent pipe flow. The focus is on very large-scale motions. Both analyses permit the observation of streamwise waviness in the large flow structures and how the transpiration can inhibit fluctuation in locali...
متن کاملExtensional-flow-induced crystallization of isotactic polypropylene
A filament stretching extensional rheometer with a custom-built oven was used to investigate the effect of uniaxial flow on the crystallization of polypropylene. Prior to stretching, samples were heated to a temperature well above the melt temperature to erase their thermal and mechanical histories and the Janeschitz-Kriegl protocol was applied. The samples were stretched at extension rates in ...
متن کاملTurbulence Transition in Pipe Flow
Pipe flow is a prominent example among the shear flows that undergo transition to turbulence without mediation by a linear instability of the laminar profile. Experiments on pipe flow, as well as plane Couette and plane Poiseuille flow, show that triggering turbulence depends sensitively on initial conditions, that between the laminar and the turbulent states there exists no intermediate state ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Physical Review Fluids
سال: 2019
ISSN: 2469-990X
DOI: 10.1103/physrevfluids.4.103908