5,001 research outputs found
Using primary instability analysis for determination of apparent liquid viscosity at jet breakup atomizing non-Newtonian Fluids
An internal mixing twin-fluid atomizer used for the application of cavity wax in automotive engineering is investigated. At typical pressures of 100 bars the wax material is atomized into a chamber and mixed with air at elevated pressures between 4 and 6 bars. The formed two-phase flow is further flowing along a straight tube and finally discharging through a number of radially arranged orifices undergoing a secondary atomization process. The original aim of these investigations is to provide inlet and boundary conditions for numerical simulations of the unsteady film formation on the substrate. Applying a number of optical measuring techniques, the initial secondary disintegration process, initial droplet velocities and droplet size distributions could be determined. In general, it was found that at typical distances between 10 and 20 mm between nozzle and target surface the disintegration process is not yet completely finished. Due to high initial velocities of more than 100 m/s in the spray centre, the wax material deposits to a large extent in the form of ligaments. Therefore, the measured droplet size distributions can only be taken as a rough indication for the length scales of the droplets and ligaments
Mass Flow Scaling of Gas-Assisted Coaxial Atomizers
This study aims to derive basic principles for liquid mass flow scaling of gas-assisted coaxial nozzles. Four liquid mass flow steps were investigated in the range of M = 20–500 kg·h, applying four atomizers with similar geometry designed at We = const. High-speed camera and phase Doppler anemometer were utilized to detect the local droplet size distribution. To estimate a reliable measurement plane, a detection method and determination according to the free jet theory was used. The resulting droplet size was analyzed, applying the aerodynamic Weber number, as well as the gas momentum flow. An empirical model was derived out of the measured data, which allows for liquid mass flow scaling when process parameters such as GLR, liquid mass flow, and required Sauter mean diameter are specified. The model was developed as a first step towards liquid mass flow scaling of gas-assisted coaxial atomizers within the investigated range of operating conditions
Effects of the 2014 major Baltic inflow on methane and nitrous oxide dynamics in the water column of the Central Baltic Sea
Peer reviewe
The process gg -> WW as a background to the Higgs signal at the LHC
The production of W pairs from the one-loop gluon fusion process is studied.
Formulas are presented for the helicity amplitudes keeping the top mass finite,
but all other quark masses zero. The correlations among the leptons coming from
the W bosons are kept. The contribution of this background to the Higgs boson
search in the WW decay mode at the LHC is estimated by applying the cuts
foreseen in experimental searches using the PYTHIA Monte Carlo program.
Kinematic distributions for the final state leptons are compared to those of
the Higgs boson signal and of the q qbar -> WW background. After applying final
cuts, the gg background is found to be large, at the level of 35% of the q qbar
background.The characteristics of the gg background are very similar to those
of the signal. Therefore, an experimental normalization of this background
component appears to be very difficult and the uncertainty must largely be
determined by theory. As a result, the significance of a Higgs signal in the gg
-> H -> WW mode at the LHC is reduced.Comment: 24 pages, 4 figure
Multi-color live-cell STED nanoscopy of mitochondria with a gentle inner membrane stain
Capturing mitochondria's intricate and dynamic structure poses a daunting challenge for optical nanoscopy. Different labeling strategies have been demonstrated for live-cell stimulated emission depletion (STED) microscopy of mitochondria, but orthogonal strategies are yet to be established, and image acquisition has suffered either from photodamage to the organelles or from rapid photobleaching. Therefore, live-cell nanoscopy of mitochondria has been largely restricted to 2D single-color recordings of cancer cells. Here, by conjugation of cyclooctatetraene to a benzo-fused cyanine dye, we report a mitochondrial inner-membrane (IM) fluorescent marker, PK Mito Orange (PKMO), featuring efficient STED at 775 nm, strong photostability and markedly reduced phototoxicity. PKMO enables super-resolution recordings of inner-membrane dynamics for extended periods in immortalized mammalian cell lines, primary cells, and organoids. Photostability and reduced phototoxicity of PKMO open the door to live-cell 3D STED nanoscopy of mitochondria for three-dimensional analysis of the convoluted IM. PKMO is optically orthogonal with green and far-red markers allowing multiplexed recordings of mitochondria using commercial STED microscopes. Using multi-color STED, we demonstrate that imaging with PKMO can capture the sub- mitochondrial localization of proteins, or interactions of mitochondria with different cellular components, such as the ER or the cytoskeleton at sub-100 nm resolution. Thereby, this work offers a versatile tool for studying mitochondrial inner-membrane architecture and dynamics in a multiplexed manner
Проектирование участка классификации золошлаковых материалов с разработкой основного оборудования
Выпускная квалификационная работа 65 с., 2 рис., 1 табл., 14 источников
Ключевые слова: сито, вибрация, проект, зола, шлаки.
Объектом исследования является золошлаковые материалы ТЭЦ ЗАТО г. Северск, Томская обл.
Цель работы–проектирование вибросита для разделения золошлаковых материалов на фракции
В процессе исследования проводились технологический расчет, конструктивный расчет, расчет деталей грохота
В результате был спроектирован виброгрохот для разделения на две фракции золошлаковых материалов
Основные конструктивные, технологические и технико-эксплуатационные характеристики: Производительность - 100 т/ч, размеры просеивающей поверхности,м (ширина – 1,2; длина 2.5), 1 ярус
В будущем планируется изготовить сито и провести его испытанияFinal qualifying work 65 p., 2 fig., 1 tab., 14 sources
Keywords: sieve, vibration, draft, ash, slag.
The object of this study is to slag materials CHP ZATO Seversk, Tomsk region.
The aim of the design-vibrating screens to separate materials into fractions of ash
The study carried out technological calculation, structural calculation, payment details screen
As a result, vibrating screen was designed to separate into two fractions ash materials
The basic constructive, technological and technical and operational characteristics: Capacity - 100 t / h, the size of the screening surface, m (width - 1.2, length 2.5), tier 1
In the future it is planned to make a screen test and hold i
Entrained Flow Gasification Part 1 : Gasification of Glycol in an Atmospheric-pressure Experimental Rig
Three coordinated papers are presented concerning entrained flow gasification of a liquid fuel under atmospheric conditions. The work is based on a detailed mapping of process parameters inside the entrained flow gasifier and at the gasifier outlet. In this paper the experimental setup and the experimental data are reported. Mono ethylene glycol (MEG) is used as a well-defined surrogate fuel for biogenic oils. The overall performance of the reactor is evaluated by measuring the gas-phase composition at the reactor outlet; radial profiles of gas-phase composition (CO₂, CO, H₂, CH₄, hydrocarbons) and temperature at 300 and 680 mm distances from the burner are measured to describe the mixing and reaction pattern in the gasifier. Global and local species balances are used to derive data that are not accessible by measurement. Characteristic parameters, i.e. stoichiometry, carbon conversion and water gas shift temperature, are derived to assess consistency of the measured data. Droplet size distribution and droplet velocity at the burner nozzle are reported based on atomization test rig experiments and direct measurements in the burner near field under gasification conditions. The experiments show a free jet with a strong outer recirculation zone as core gasification pattern. The measured species concentrations and temperatures provide an insight into both the mixing and the reactions in the burner near field. The water gas shift equilibrium is reached for a temperature of 1495 K upstream of the gasifier outlet. Hydrocarbons are not completely converted due to the low temperatures near the gasifier outlet. The research work has been conducted within the research cooperation of the Helmholtz Virtual Institute HVIGasTech
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