Search results for "buoy"
showing 10 items of 56 documents
Numerical analysis of density gradient centrifugation profiles from eukaryotic DNA
1990
A numerical method for the deconvolution of superimposed Gaussian distributions with a unique solution has been proposed by Medgyessy [10]. We have tested the usefulness of this method for the analysis of density gradient centrifugation profiles from eukaryotic DNA, which are normally composed from overlapping Gaussian distributed profiles of several subcomponents with different mean buoyant densities. From the analysis of human DNA and from model calculations we conclude that major subcomponents can be identified by this method, if they differ in their buoyant density by approximatly 0.005 g/ml. Minor components can only be identified if the total DNA has been fractionated according to buo…
A Innovative Monitoring Underwater Buoy Systems (MUnBuS) for Marine and Rivers installation with IR-Cam, Instrumental Telemetry and Acoustic Data Acq…
2015
The proposed low cost systems shows the results obtained in the implementation and testing in marine environment of a Innovative Monitoring Underwater Buoy Systems for Marine and Rivers installation with IR-Cam, Instrumental Telemetry and Acoustic Data Acquisition Capability (MUnBuS). This concerning a innovative Monitoring Underwater Buoy Systems that can be remotely controlled from the ground, air, satellite and sea and from a Center of Supervision Telecontroller And Data Acquisition and Monitoring (Mobile-STADAM Center). The Buoy is hosts for the radio or satellite communication equipment, the downloading and telemetering data equipment and the photovoltaic power supply, board and underw…
A security and surveillance application of the innovative Monitoring Underwater Buoy Systems (MUnBuS) on the Protected Marine Area (AMP) of capo gall…
2015
The proposed low cost systems shows the results obtained in the implementation and testing on real security application to Protected Marine Area surface and submarine environment of a innovative Monitoring Underwater Buoy Systems (MUnBuS) for installation with IR-CCTV-Cam, ultrasonic dolphin warning system and Green Laser Perimeter Detection. This concerning innovative Monitoring Underwater Buoy Systems that can be remotely controlled from the ground, air, satellite and sea and from a Center of Supervision Telecontroller And Data Acquisition and Monitoring (Mobile- STADAM Center). The Buoy is hosts for the radio or satellite communication equipment, the downloading and telemetering data equ…
Mass transfer in nonisothermal ferrocolloids under the effect of a magnetic field
1999
Abstract The paper presents a review of newest experimental results on particle thermal diffusion in hydrocarbon based ferrofluids. The measurements are performed using a vertical thermal diffusion column, the Soret coefficient is evaluated from particle separation curves employing a simple column theory which accounts for thermal convection in the vertical channel forced by a concentration buoyancy force arising during the thermophoretic transfer of heavy particles. High positive values of the Soret coefficient of lyophilized Fe 3 O 4 and Mn x Zn 1− x Fe 2 O 4 particles in surfacted tetradecane based colloids are measured. Experiments confirm the theoretically predicted anisotropy of parti…
Thermophoretic separation of ultrafine particles in ferrofluids in thermal diffusion column under the effect of an MHD convection
2000
The aim of the paper is to evaluate the Soret coeAcient ST of colloidal particles in ferrofluids from measurements of an unsteady particle separation in a flat thermodiAusion column. The column theory is modified taking into account MHD eAects of thermal convection aAected by a concentration buoyancy force. It is shown that the Hartmann eAect, not only in hydrocarbon based colloids but also in ionic magnetic fluids of relatively high electric conductivity, does not influence significantly the particle separation dynamics. From measurements, positive values of ST of surfacted particles in tetradecane based colloids are calculated. An anisotropy of the Soret eAect in the presence of a uniform…
Microwave heating of water in a rectangular waveguide: Validating EOF-Library against COMSOL multiphysics and existing numerical studies
2019
The purpose of this work is two-fold: first, we successfully validate our open-source tool EOF-Library, which efficiently couples Elmer FEM and OpenFOAM, against COMSOL Multiphysics, a commercial simulation package; second, we inform about significant discrepancies between our results and the experimental and simulation data found in a series of research papers. We reproduce the previously published numerical simulations wherein microwaves are supplied to a water domain through a rectangular waveguide, inducing convective flow. This is a conjugate problem with weakly coupled electromagnetics, heat transfer and fluid dynamics. It involves effects such as permittivity dependence on temperatur…
Determination of the Soret coefficient of magnetic particles in a ferrofluid from the steady and unsteady part of the separation curve
2004
Experiments on the particle separation in a vertical thermodiffusion column are used to investigate the separation (Soret effect) in ferrofluids. The use of a two-sectional column with internal walls of low thermal capacity allows analyzing the initial part of the unsteady separation curves as well as the steady state regime. The Soret coefficient calculated from the measurements of the separation dynamics agrees well with the one found from the steady separation limit reached in long-time experiments especially if the solutal buoyancy is low.
One-dimensional Mixed MHD Convection
2006
The parallel, fully developed flow of an electrically conducting fluid between plane parallel walls under the simultaneous influence of a driving pressure head, buoyancy, and magnetohydrodynamic (MHD) forces is studied. The fluid is assumed to be internally heated and the flow is modeled as one-dimensional and incompressible, while the Boussinesq approximation is adopted for the buoyancy terms. Analytical solutions are obtained for temperature, velocity and electrical potential under different electrical boundary conditions, forced to natural convection intensity ratios and values of the magnetic induction. Generalized working charts are presented which synthetically describe the system''s …
On the influence of gravitational and centrifugal buoyancy on laminar flow and heat transfer in curved pipes and coils
2015
Abstract The effects of gravitational and centrifugal buoyancy on laminar flow and heat transfer in curved and helical pipes were investigated by numerical simulation. Six dimensionless numbers characterizing the problem were identified, and an analysis was conducted on the possible combinations of signs of the gravitational and centrifugal buoyancy effects. Two distinct Richardson numbers were introduced in order to quantify the importance of the two types of buoyancy, and it was shown that, in the case of heating from the wall, a maximum realizable value of the centrifugal Richardson number exists which is a linear function of the curvature δ (ratio of pipe radius a to curvature radius c)…
Near real-time estimation of Sea and Land surface temperature for MSG SEVIRI sensors
2020
Abstract Land and Sea Surface Temperatures (LST and SST) are both recognized as Essential Climate Variables, and are routinely retrieved by a wealth of satellites. However, for validated approaches, the latest data are usually not available to the general public. We offer to bridge this gap, by using Meteosat Second Generation (MSG) Spinning Enhanced Visible and InfraRed Imager (SEVIRI), with its 15 min temporal resolution. Here, we present generic algorithms for the retrieval of both LST and SST, valid for the SEVIRI instrument onboard MSG platforms 8–11, which we validate using hourly data of 4 ground stations and 11 buoys in Spain over the years 2015 to 2018. These validations show that …