Living in water imposes severe constraints on the evolution of the vertebrate body. As a result of these constraints, numerous extant and extinct aquatic vertebrate groups evolved convergent osteological and soft-tissue adaptations. However, one important suite of adaptations is still poorly understood: dermal cover morphologies and how they influence surface fluid dynamics. This is especially ...

an experimental study was carried out on the wake of a cylinder on the back of which a plate is installed parallel to the fluid flow, with different terminal angles, where the reynolds number is 50000. at the end of the plate, blades with the height of 0.25 equal to the cylinder diameter and with 45, 90 and 135 degrees angle from the horizon, are installed where the cylinder diameter is equal t...

this paper presents efflux time experiments performed in the absence and presence of aqueous solutions of drag reducing agents (dras) when a liquid is emptied from a large open cylindrical storage tank through an exit piping system. the drag reducing agents studied are dodecyl benzene sulfonate anionic surfactant and a mixed solution of surfactant and sodium chloride counter ion. the variables ...

Gas–solid momentum transfer is a fundamental problem that is characterized by the dependence of normalized average fluid–particle force F on solid volume fraction / and the Reynolds number based on the mean slip velocity Rem. In this work we report particle-resolved direct numerical simulation (DNS) results of interphase momentum transfer in flow past fixed random assemblies of monodisperse sph...

Abstract This paper deals with the analysis of fluid flow around bluff bodies using computational dynamics. Two-dimensional rectangular body, semi-circular tip, triangular tip and elliptical nose cone shapes have been considered in paper. The are analysed at various Mach numbers, ranging from 1.5 to 10. aerodynamic characteristics like Drag coefficient drag force investigated. Also, formation s...

G-quadruplexes represent a novelty for molecular biology. Their role inside the cell remains mysterious. We investigate a possible correlation with mRNA localization. In particular, we hypothesize that G-quadruplexes influence fluid dynamics. Localization of mRNA molecules within the cytoplasm recently emerged as a prevalent mechanism for cell polarization, thus underlying developmental process...

Synodontis nigriventris is a surface-feeding facultative air-breather that swims inverted with its zoological ventral side towards the water surface. Their near-surface drag is about double the deeply submerged drag (due to wave drag) and roughly twice the sum of frictional and pressure drags. For streamlined technical bodies, values of wave drag augmentation near the surface may be five times ...

To investigate the effect of group gliding formation on hydrodynamic performance manta rays, numerical simulations were used to drag, lift and pressure distribution multiple rays in tandem, triangular diamond-shaped arrangements. The simulation results show that leader ray at head always suffers least most cases, companion tail drag. flow field shows drag reduction mainly comes from high low zo...

In the computational fluid dynamics (CFD) modeling of gas-solids two phase flow, the effect of boundary conditions play an important role in predicting the hydrodynamic characteristics of fluidized beds. In this work, the hydrodynamics of conical fluidized bed containing dried TiO2 nano-agglomerates were studied both experimentally and computationally. The pressure drop ...

A Lagrangian-Eulerian numerical scheme for the investigation of bubble motion in turbulent flow is developed. The flow is analyzed in the Eulerian reference frame while the bubble motion is simulated in the Lagrangian one. Finite volume scheme is used, and SIMPLEC algorithm is utilized for the pressure and velocity linkage. The Reynolds stresses are modeled by the RSTM model of Launder. Upwind ...