Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 15 of 15 for “"Drop size distributions"”.
-
Modelling of Rainfall Drop Size Distributions for Application in Fade Prediction on Earth-Space Paths
… measurement of rain rate and rainfall drop size distribution (DSD) at the earth station location. <br/><br/>This thesis fits the standard lognormal and gamma distributions to one-minute slices of rainfall DSDs captured between 2003 and 2013 at the Chilbolton Observatory in southern …
-
Study of slant path attenuation ratios derived from a dual-polarized radar
… which used a dual-polarized radar to estimate drop size distributions on a slant path between Blacksburg, Virginia, and the Intelsat VA F10 satellite. The effect of varying drop size distributions on attenuation ratios is discussed. An uplink power control simulation is developed using the …
-
The separation of secondary oil-water dispersions in particulate beds
… coalescence mechanisms, and models by which droplets <100 μm are collected, coalesced and transferred, have been reviewed with particular reference to particulate bed coalescers. The separation of secondary oil-water dispersions was studied experimentally using packed beds of monosized glass …
-
Adaptive power control as a fade countermeasure on satellite links
… shows more promise for ULPC. Differences in drop size distributions during a rain storm will result is different scaling factors. If the downlink attenuation is limited to 6 dB at 20 GHz, real time scaling can be accomplished. A scaling type ULPC algorithm driven by downlink attenuation is …
-
RELAMPAGO-CACTI drop size distribution observations and the implications for cloud and hydrologic studies
Comparisons of drop size distributions (DSD) properties and rainfall modes among three deep convective regions (the U.S. Southern Great Plains, in Córdoba Province in subtropical South America, and Manacapuru in central Amazonia) where heavy rain-producing systems contribute the majority of …
-
Breakup and coalescence in turbulent two-phase flows
… in two-phase systems will cause the bubbles or drops of a dispersion to undergo breakup and coalescence, and the resulting changes in the dispersion may significantly affect the engineering process under consideration. For this reason, many researchers have studied breakup and coalescence in …
-
Mechanisms of liquid extraction in a pilot plant sieve plate column
The literature pertinent to droplet hydrodynamics and mass transfer in perforated (sieve)plate liquid-liquid extractor columns has been reviewed. An experimental investigation was conducted in a 450 mm diameter perforated plate extractor with four plates using four different designs with holes of …
-
The atomisation of detergent slurries
… determine the conditions under which the optimum droplet size distribution (ie., narrowest size range with a minimum of fines and over-sized agglomerates), is generated in sprays from centrifugal pressure nozzles. A range of non-Newtonian detergent slurries were tested but the results are of wider …
-
The study and real-time implementation of attenuation correction for X-band dual-polarization weather radars
… waves caused by oblate, highly oriented raindrops can be estimated using the specific differential phase. This advance leads to correction of the measured reflectivity (Zh) and the differential reflectivity (Zdr) due to path attenuation. This thesis addresses via theory, simulations and data …
-
Solvent extraction of phosphoric acid
… concentration, but power input had no effect. Drop size was found to reduce with acid concentration and power input. For the continuous studies a novel horizontal mixer~settler cascade was designed, constructed and operated using pure and impure acid with MIBK as the solvent. The cascade …
-
Study of the Performance of a Large Mechanically-Agitated Extraction Column
… extraction columns and relevant phenomena eg. droplet break-up and coalescence, axial mixing, single drop mass transfer mechanisms and flooding/phase-inversion, and related mathematical models have been reviewed. An experimental study was performed of the hydrodynamic and mass transfer …
-
A study of liquid-liquid extraction in a sieve plate column
… surveyed. Mass transfer characteristics during drop formation, rise and coalescence, and related models were also reviewed. Important design parameters i.e. flooding, dispersed phase hold-up, drop size distribution, mean drop size, coalescence/flocculation zone height beneath a plate and jetting …
-
Liquid-liquid extraction in a pilot scale rotating disc contactor
… of extractor and the relevant phenomena, such as droplet break-up and coalescence, drop mass transfer and axial mixing has been revjewed. Experiments were performed using the system C1airsol-350-acetone-water and the effects of drop size, drop size-distribution and dispersed phase hold-up on the …
-
Trade wind cloud evolution observed by polarization radar: relationship to aerosol characteristics
… found that giant nuclei do influence the rain drop size distributions as larger drops were present above cloud base when the giant nuclei concentrations below cloud base were greater. The Z and ZDR fields show better temporal and spatial correlation when the giant nuclei concentrations were …
-
Characterization and modeling of aerosol-cloud interactions toward the improvement of rainfall estimation in high mountains
… results from the vertical evolution of the rain drop-size distributions (RDSDs). Explicit modeling of the rainfall microphysics from the top of the blind zone, if located below the zero-degree isotherm, towards the surface can improve rainfall estimation at the ground, as demonstrated in the …