Showing papers by "Sanjoy Banerjee published in 2006"
TL;DR: The technique couples dynamic self-consistent field theory with continuum hydrodynamics and flow penalization to simulate polymeric fluid flows in channels of arbitrary geometry and finds that surface wetting effects and shear effects compete, producing wall-perpendicular lamellae in the absence of flow and wall-parallel lamella in cases where the shear rate exceeds some critical Weissenberg number.
Abstract: We introduce a mesoscale technique for simulating the structure and rheology of block-copolymer melts and blends in hydrodynamic flows. The technique couples dynamic self-consistent field theory with continuum hydrodynamics and flow penalization to simulate polymeric fluid flows in channels of arbitrary geometry. We demonstrate the method by studying phase separation of an ABC triblock copolymer melt in a submicron channel with neutral wall wetting conditions. We find that surface wetting effects and shear effects compete, producing wall-perpendicular lamellae in the absence of flow and wall-parallel lamellae in cases where the shear rate exceeds some critical Weissenberg number.
23 citations
TL;DR: In this paper, the velocity of a microchannel flow was determined by atomic force microscopy (AFM) using a 50nm wide "whisker", which was partially submerged and scanned transverse to the flow while drag was recorded.
Abstract: The velocity of a microchannel flow was determined by atomic force microscopy (AFM) using a 50nm wide “whisker,” which was partially submerged and scanned transverse to the flow while drag was recorded. A peaked, near parabolic, flow velocity profile was found. Particle image velocity (PIV) measurements using 70nm diameter quantum-dot-coated polystyrene spheres confirmed the shape of the AFM-measured velocity profile. AFM-based nanometer resolution velocimetry confirms that the drag-velocity relationship for the whisker remains consistent over a wide range of shear values and appears to successfully resolve submicron scale flows, which are beyond the limits of conventional PIV measurements.
12 citations
01 Jan 2006
TL;DR: In this article, the physics of turbulent mixing and clustering are discussed, and a direct numerical simulation of turbulent reacting flows involving dilute particles is presented, followed by a detailed discussion of the physics and control of wall turbulence.
Abstract: Stable stratified, wall bounded, turbulent flows p. 49 Physics and control of wall turbulence p. 59 The physics of turbulent mixing and clustering p. 69 LES of premixed flame longitudinal wave interactions p. 77 Direct numerical simulation of reacting turbulent multi-species channel flow p. 85 DNS/MILES of reacting air/H[subscript 2] diffusion jets p. 93 Direct numerical simulation of turbulent reacting flows involving dilute particles p. 101
1 citations