Polymer induced drag reduction in turbulent pipe flow was investigated using a non-intrusive laser based diagnostic technique, namely Particle Image Velocimetry (PIV). The drag reduction was measured in a pressure-driven flow facility, in a horizontal pipe of inner diameter 25.3 mm at Reynolds numbers ranging from 35 000 to 210 000. Three highmolecular-weight polymers (polyethylene oxide 2×10 6...

In this study, a numerical computational fluid dynamics study is conducted in order to predict the aerodynamic forces on the NP car. The turbulent air flow around the car is modeled using the realizable k-ε model. First, results are validated against those presented for the Ahmed’s body. Next, the fluid flow around the car is simulated for different car speeds ( to mph) and fl...

in this paper, the transient inertial viscoelastic flow around a circular cylinder is investigated numerically. a second order finite-volume method is used to increase the numerical accuracy. here, the giesekus model is used as the constitutive equation. this nonlinear model has prominent ability in describing normal stress differences and viscosity in power-law regions. the impacts of the elas...

Stokes Paradox, Fluid dynamics, Stokes flow, Stream function, Biharmonic equation, Helmholtz equation, Low Reynolds number This paper proposes a solution to Stokes’ paradox for asymptotically uniform viscous flow around a cylinder. The existence of a global stream function satisfying a perturbative form of the two-dimensional Navier–Stokes equations for low Reynolds number is established. This ...

Bubble column reactors suffer from bubble coalescence resulting in a decreased mass transfer efficiency. In order to increase the mass transfer rate in bubble column reactors, a novel reactor is proposed, the Micro-Structured Bubble Column (MSBC). is novel reactor makes use of a wire-mesh serving the purpose of cuing bubbles into smaller bubbles. is increases the specific bubble surface area...

Three different polysaccharides, aloe vera, Tamarind powder and pineapple fibers, are utilized as drag reducing agents in a turbulent flow. Using a Taylor–Couette setup, consisting of a rotating inner cylinder, for measuring the drag reduction, a range of Reynolds numbers from 4 × 104 to 3 × 105 has been explored in this study. The results are in good agreement with previous studies on polysacc...

Bubble column reactors suffer from bubble coalescence resulting in a decreased mass transfer efficiency. In order to increase the mass transfer rate in bubble column reactors, a novel reactor is proposed, the Micro-Structured Bubble Column (MSBC). is novel reactor makes use of a wire-mesh serving the purpose of cuing bubbles into smaller bubbles. is increases the specific bubble surface area...

Bubble column reactors suffer from bubble coalescence resulting in a decreased mass transfer efficiency. In order to increase the mass transfer rate in bubble column reactors, a novel reactor is proposed, the Micro-Structured Bubble Column (MSBC). is novel reactor makes use of a wire-mesh serving the purpose of cuing bubbles into smaller bubbles. is increases the specific bubble surface area...