Drag polymer-induced

H.J. Choi and M.S. Jhon, Polymer-induced turbulent drag reduction, Industrial Engineering Chemistry Research, 35(9) 2993-2998, January 1996. 

The drag reduction is connected with a reduction in the burst frequency and structure, which is closely associated with the strong polymer-induced increase in elongational viscosity. Here, it must be taken into account that the elongation of the polymer... 

Armstrong R, Jhon MS (1984) A self-consistent theoretical approach to polymer induced turbulent drag reduction Chem Eng Commun 30 99... 

Beris, A.N. Dimitropoulos, C.D. Sureshkumar, R. Handler, R.D. Direct numerical simulations of polymer-induced drag reduction in viscoelastic turbulent channel flows. Proceedings of the International Congress on Rheology, Cambridge, U.K., Aug 20-25 British Society of Rheology Glasgow, 2000 Vol. 2, 190-192. 

Choi, H. J., Kim, C. A., Vinay, S. J., and Jhon, M. S., Effect of degradation on polymer-induced turbulent drag reduction. Book of Abstracts, 219th ACS National Meeting, San Francisco, Mar. 26-30, 2000, POLY-184, 2000b. 

An Experimental Study of Polymer Induced Drag for Flows Through Porous Medium... 

Armstrong, R. and M. S. Jhon A Self-Consistent Theoretical Approach to Polymer Induced Turbulent Drag Reduction. Dept. Chem. Eng., Carnegie-Mellon University (personal communication) 1984. 

Dimitropoulos, C.D., Dubief, Y., Shaqfeh, E.S.G., and Moin, P. (2006) Direct numerical simulations of polymer-induced drag reduction in turbulent boimdary layer flow of inhomogeneous polymer solutions. /. Fluid Mech., 566, 153-166. 

Housiadas, K.D. and Beris, A.N. (2003) Polymer-induced drag reduction effects of the variations in elasticity and inertia in turbulent viscoelastic channel flow. Phys, Buids, 15, 2369-2384. 

Li, W. and Graham, M.D. (2007) Polymer induced drag reduction in exact coherent structures of plane Poiseuille flow. Phys. Fluids, 19, 083101. (15 pages). 

The unit can be fed polymer in the particulate solids form or as strips, as in the case of rubber extrusion. The solids (usually in pellet or powder form) in the hopper flow by gravity into the screw channel, where they are conveyed through the solids conveying section. They are compressed by a drag-induced mechanism in the transition section. In other words, melting is accomplished by heat transfer from the heated barrel surface and by mechanical shear heating. 

The steady and dynamic drag-induced simple shear-flow rheometers, which are limited to very small shear rates for the steady flow and to very small strains for the dynamic flow, enable us to evaluate rheological properties that can be related to the macromolecular structure of polymer melts. The reason is that very small sinusoidal strains and very low shear rates do not take macromolecular polymer melt conformations far away from their equilibrium condition. Thus, whatever is measured is the result of the response of not just a portion of the macromolecule, but the contribution of the entire macromolecule. 

The former drags the polymer melt toward the exit, whereas the latter induces crosschannel mixing. 

Liberatore, M. W., PoUauf, E. J., and McHugh, A. J., Shear-induced structure formation in solutions of drag reducing polymers, J. Non-Newtonian FluidMech, 113, 193-208 (2003). 

---