Search results for "fluid"
showing 10 items of 5513 documents
Spatial dispersion intensity measure of phase concentration distributions and its applications to quantitative characterization, distinguishing and c…
2008
A method of evaluation of spatial dispersion of structures is presented. A quantitative parameter measuring spatial dispersion is introduced. It is shown that this parameter indeed measures spatial dispersion. A classification of bubble flow structures based on values of this parameter is proposed. An example of application of the method to real flow structures is presented.
Large-eddy simulations of turbulent flow with heat transfer in simple and complex geometries using Harwell-FLOW3D
1996
Abstract Large-eddy simulation (LES) results are presented and discussed for the turbulent flow with heat transfer in different geometrical configurations, including a plane channel, a channel bearing transverse square ribs on one of the walls, and a crossed-corrugated air heater. They were obtained using the computational fluid dynamics (CFD) code Harwell-FLOW3D (Release 2), finite-volume grids having up to 423 nodes, and the Smagorinsky subgrid model with several variants regarding near-wall damping and wall boundary conditions. The first problem (plane turbulent Poiseuille flow with heat transfer) was mainly used as a benchmark to investigate the influence of numerical methods (pressure-…
Morphological similarities between DBM and an economic geography model of city growth
2009
International audience; An urban microeconomic model of households evolving in a 2Dcellular automata allows to simulate the growth of a metropolitan area whereland is devoted to housing, road network and agricultural/green areas. Thissystem is self-organised: based on individualistic decisions of economic agentswho compete on the land market, the model generates a metropolitan area withhouses, roads, and agriculture. Several simulation are performed. The resultsshow strong similarities with physical Dieletric breackdown models (DBM). Inparticular, phase transitions in the urban morphology occur when a controlparameter reaches critical values. Population density in our model and theelectric …
Multifibrillar bundles of a self-assembling hyaluronic acid derivative obtained through a microfluidic technique for aortic smooth muscle cell orient…
2018
A hyaluronic acid derivative that is able to physically crosslink in a saline aqueous environment was employed for the production of fibers with a mean diameter of 50 μm using a microfluidic technique. The microfibers were collected in a tailored rotating collector and assembled to form multifibrillar bundles. The orientation of the microfibers on the collected bundles was evaluated by microCT analysis. The bundles were biofunctionalized by physical addition of fibronectin or chemical tethering of a cyRGDC peptide to achieve control of Aortic Smooth Muscle Cell (AoSMC) attachment, elongation and alignment. The mechanical performances of these bundles were evaluated by elongation tests, rela…
Real-time data processing in the ALICE High Level Trigger at the LHC
2019
At the Large Hadron Collider at CERN in Geneva, Switzerland, atomic nuclei are collided at ultra-relativistic energies. Many final-state particles are produced in each collision and their properties are measured by the ALICE detector. The detector signals induced by the produced particles are digitized leading to data rates that are in excess of 48 GB/$s$. The ALICE High Level Trigger (HLT) system pioneered the use of FPGA- and GPU-based algorithms to reconstruct charged-particle trajectories and reduce the data size in real time. The results of the reconstruction of the collision events, available online, are used for high level data quality and detector-performance monitoring and real-tim…
Spatial differences and temporal changes in illicit drug use in Europe quantified by wastewater analysis
2014
Aims To perform wastewater analyses to assess spatial differences and temporal changes of illicit drug use in a large European population. Design Analyses of raw wastewater over a 1-week period in 2012 and 2013. Setting and Participants Catchment areas of wastewater treatment plants (WWTPs) across Europe, as follows: 2012: 25 WWTPs in 11 countries (23 cities, total population 11.50 million); 2013: 47 WWTPs in 21 countries (42 cities, total population 24.74 million). Measurements Excretion products of five illicit drugs (cocaine, amphetamine, ecstasy, methamphetamine, cannabis) were quantified in wastewater samples using methods based on liquid chromatography coupled to mass spectrom…
Ability of the ISAS3Fun Method to Detect Sperm Acrosome Integrity and Its Potential to Discriminate between High and Low Field Fertility Bulls
2021
The objective of the present study was to investigate whether fertility differences in bulls are reflected in variations of sperm quality when analysing only one ejaculate per male. Two experiments were performed. In the first experiment, frozen semen samples from 20 adult bulls were tested
Development of a microfluidic design for an automatic lab-on-chip operation
2016
Simple and easy to use are the keys for developing lab-on-chip technology. Here, a new microfluidic circuit has been designed for an automatic lab-on-chip operation (ALOCO) device. This chip used capillary forces for controlled and precise manipulation of liquids, which were loaded in sequence from different flowing directions towards the analysis area. Using the ALOCO design, a non-expert user is able to operate the chip by pipetting liquids into suitable inlet reservoirs. To test this design, microfluidic devices were fabricated using the programmable proximity aperture lithography technique. The operation of the ALOCO chip was characterized from the flow of red-, blue- and un-dyed deioni…
Microthermometry of fluid inclusions in calcite from Fuerteventura carbonatites: composition and formation conditions
2022
The petrographic analysis in calcite minerals in carbonatitic dykes from Fuerteventura Basal Complex (Ajuy, Punta de la Nao) shows the presence of isolated primary fluid inclusions, corroborating their magmatic origin instead of a late-stage origin. Micro-thermometric studies in calcite show a restricted range of apparent eutectic temperature (Te*= -21.7 – -21.0 °C) and final ice melting temperatures (Tim= -3.2 – -2.1. °C). Homogenization temperatures and pressures are in the range of 140-210 °C and 4-16 bars respectively. Our results suggest the binary NaCl-H2O system as a characterizing chemical system in studied fluid inclusions, with the presence of low salinity fluids (≈ 5 wt. % NaCleq…
The role of patient specific morphology and contractility of the left atrial appendage on the thromboembolic risk in atrial fibrillation
2022
The vast majority of thrombi that cause ischemic complications in atrial fibrillation originate in the left atrial appendage. The left atrial appendage is an anatomical structure that starts from the left atrium, characterized by a wide morphological variability between individuals. This work analyses simulated hemodynamic for different patient-specific models of the left atrial appendage, using computational fluid-structure interaction studies, modelling the effect of changes in contractility and shape resulting from atrial fibrillation. Three operating conditions were analysed: sinus rhythm, acute atrial fibrillation, and chronic atrial fibrillation. These were simulated on four patient-s…