Biofilms were grown from wild-type (WT) Pseudomonas aeruginosa PAO1 and the cell signaling lasI mutant PAO1-JP1 under laminar and turbulent flows to investigate the relative contributions of hydrodynamics and cell signaling for biofilm formation. Various biofilm morphological parameters were quantified using Image Structure Analyzer software. Multivariate analysis demonstrated that both cell si...

Hydrodynamic conditions control two interlinked parameters; mass transfer and drag, and will, therefore, significantly influence many of the processes involved in biofilm development. The goal of this research was to determine the effect of flow velocity and nutrients on biofilm structure. Biofilms were grown in square glass capillary flow cells under laminar and turbulent flows. Biofilms were ...

An experimental study is conducted to determine local heat-transfer performance and mechanisms in radial flow through two parallel heated disks. Three distinct heat-transfer mechanisms are disclosed along the flow passage: steady laminar, periodic laminar, and turbulent. The heat-transfer performance is enhanced proportional to the 0.5 and 0.8 powers of Reynolds number, in the steady periodic a...

The numerical simulation of flows over large-scale wind turbine blades without considering the transition from laminar to fully turbulent flow may result in incorrect estimates of the blade loads and performance. Thanks to its relative simplicity and promising results, the Local-Correlation based Transition Modelling concept represents a valid way to include transitional effects into practical ...

In the design of flow geometries consisting channels such as high-temperature gas heat exchangers, a great number parameters can be chosen, why solving turbulent Reynolds Averaged Navier-Stokes (RANS) equations by CFD coupled with other physics become computational demanding. Therefore, we here propose method for significant reduction resources and consequent high speed. This is done using less...

A laminar boundary layer separates in a region of adverse pressure gradient on a flat plate, undergoes transition, and finally the turbulent boundary layer reattaches. Laminar-turbulent transition within this laminar separation bubble (LSB) is investigated by means of measurements with a Laser-Doppler-Anemometer (LDA), flow visualization in water and direct numerical simulation (DNS). The role ...

In an electrically conducting fluid two types of turbulence with a preferred direction are distinguished: planar turbulence, in which every velocity of the turbulent ensemble of flows has no component in the given direction; and two-dimensional turbulence, in which every velocity in the turbulent ensemble is invariant under translation in the preferred direction. Under the additional assumption...