scholarly journals Correlations between the two-phase gas/liquid spray atomization and the Stokes/aerodynamic Weber numbers

2009 ◽  
Vol 147 ◽  
pp. 012057 ◽  
Author(s):  
Mohammad A Rahman ◽  
Ted Heidrick ◽  
Brian A Fleck
Keyword(s):  
Spray Atomization ◽  
Two Phase ◽  
Liquid Spray

Study on atomization particle size characteristics of two-phase flow nozzle

2021 ◽  
pp. 1-12
Author(s):  
Haoqi Lilan ◽  
Junbin Qian ◽  
Nan Pan
Keyword(s):  
Particle Size ◽  
Size Distribution ◽  
Droplet Size ◽  
High Speed ◽  
Droplet Size Distribution ◽  
Average Diameter ◽  
Spray Atomization ◽  
Two Phase ◽  
Nozzle Pressure ◽  
Local Observation

Nozzle spray atomization is widely used in industrial and agricultural production processes and is a very complicated physical change. The spray atomization of the nozzle is a process in which the droplets are continuously broken into finer particles under the action of force, in order to study the effect of nozzle atomization, that is, droplet size distribution characteristics. The experimental average mathematical model of droplet size distribution was established by introducing the average diameter of Sutter (SMD). The droplet size distribution in the atomization field of the nozzle is studied by simulation. In the experimental study, the high-speed camera, external mixing air atomizing nozzle platform experimental device and image processing were used, and the atomization field was divided into multiple observation areas. Through the measurement of several local observation areas, the droplet size distribution of the whole atomization field is constructed. It provides a reference for the study of the atomization field of the nozzle and a basis for the intuitive understanding of the droplet size distribution in the atomization field of the nozzle. The effective atomization area of the nozzle atomization was selected to study the influence of the liquid flow rate, the liquid temperature and the nozzle pressure on the atomized particle size distribution of the externally mixed atomizing nozzle. The internal law is obtained, which provides a basis and reference for effectively controlling the atomization effect in the atomization field.

EXPERIMENTAL INVESTIGATION OF GEOMETRIC SCALING ON ATOMIZATION IN A TWO-PHASE GAS/LIQUID SPRAY

2010 ◽  
Vol 22 (2) ◽  
pp. 133-155 ◽  
Author(s):  
C. E. Ejim ◽  
Mohammad Abdur Rahman ◽  
A. Amirfazli ◽  
B. A. Fleck
Keyword(s):  
Experimental Investigation ◽  
Two Phase ◽  
Geometric Scaling ◽  
Liquid Spray

Horizontal Penetration of Gas-Liquid Spray Jets in Gas-Solid Fluidized Beds

2004 ◽  
Vol 2 (1) ◽  
Author(s):  
Siva Ariyapadi ◽  
Franco Berruti ◽  
Cedric Briens ◽  
Jennifer McMillan ◽  
David Zhou
Keyword(s):  
Momentum Flux ◽  
Fluidized Beds ◽  
Nozzle Geometry ◽  
Two Phase ◽  
Gas Jets ◽  
Wide Range ◽  
Liquid Spray ◽  
Jet Penetration ◽  
Nozzle Geometries ◽  
Good Agreement

A new method has been developed to predict the horizontal jet penetration of gas-liquid sprays injected into gas-solid fluidized beds. The technique involves combining a theoretical model to predict the momentum flux of two-phase sprays with the Benjelloun et al. (1995) correlation for gas jets. Following this treatment, a generalized version of the jet penetration correlation has been developed, which includes the effect of nozzle geometry. The correlation predictions are in very good agreement with the experimental data for a wide range of nozzle geometries, nozzle scales, and jet fluids.

NUMERICAL SIMULATION OF SPRAY ATOMIZATION IN SUPERSONIC FLOWS

2010 ◽  
Vol 24 (13) ◽  
pp. 1299-1302 ◽  
Author(s):  
JIANGFENG WANG ◽  
CHEN LIU ◽  
YIZHAO WU
Keyword(s):  
Numerical Simulation ◽  
Combustion Chamber ◽  
Liquid Fuel ◽  
Rapid Development ◽  
Droplet Size Distribution ◽  
Wave Structure ◽  
Spray Atomization ◽  
Propulsion Performance ◽  
Combustion Properties ◽  
Liquid Spray

With the rapid development of the air-breathing hypersonic vehicle design, an accurate description of the combustion properties becomes more and more important, where one of the key techniques is the procedure of the liquid fuel mixing, atomizing and burning coupled with the supersonic crossflow in the combustion chamber. The movement and distribution of the liquid fuel droplets in the combustion chamber will influence greatly the combustion properties, as well as the propulsion performance of the ramjet/scramjet engine. In this paper, numerical simulation methods on unstructured hybrid meshes were carried out for liquid spray atomization in supersonic crossflows. The Kelvin-Helmholtz/Rayleigh-Taylor hybrid model was used to simulate the breakup process of the liquid spray in a supersonic crossflow with Mach number 1.94. Various spray properties, including spray penetration height, droplet size distribution, were quantitatively compared with experimental results. In addition, numerical results of the complex shock wave structure induced by the presence of liquid spray were illustrated and discussed.

scholarly journals CFD Liquid Spray Combustion Analysis of a Single Annular Gas Turbine Combustor

1999 ◽  
Author(s):  
Vanco Smiljanovski ◽  
Norbert Brehm
Keyword(s):  
Gas Phase ◽  
Computational Grid ◽  
Combustion Model ◽  
Reacting Flow ◽  
Cfd Analysis ◽  
Fuel Injector ◽  
Lean Burn ◽  
Two Phase ◽  
Radial Temperature ◽  
Liquid Spray

In this paper CFD analysis of the steady two-phase turbulent combusting flow in a single annular low-NOx combustor is presented. For this purpose the commercial code CFD-ACE (1998) was used, where Eulerian equations are solved for the gas phase and the liquid spray fuel droplets are treated in a Lagrangian frame of reference allowing for evaporation of droplets and providing source terms for the gas phase. The standard k-ε model was used for turbulence and an assumed shape probability density function was used for the instantaneous chemistry in the conserved scalar combustion model. Thermal NOx is assumed to be the only source of NOx production and is decoupled from the gas phase reacting flow and calculated in a postprocessing step. The calculation is done on a block structured multi-domain computational grid. Particular attention has be paid to the detailed modeling of the fuel injector having multiple air swirler passages starting from the trailing edge of the air swirler vanes and utilizing up to 400000 computational grid cells for the entire model. The model represents the single annular low-NOx combustor for the BR700 aircraft engine family, which is based on a Rich Burn - Quick Quench - Lean Burn (RQL) concept. CFD analysis is done for high power reduced take off conditions and is compared with full annular rig test results for the temperature traverse and the integral EINOx. The results imply satisfactory prediction capability for the EINOx and the average radial temperature distribution. The prediction of the details of the temperature traverse is not satisfactory and will remain a challenge for the future.

Synthesis and Characterization of Small Grain Sized Molybdenum Nitride Films

1996 ◽  
Vol 457 ◽  
Author(s):  
S. L. Roberson ◽  
D. Finello ◽  
R. F. Davis
Keyword(s):  
Molybdenum Oxides ◽  
Molybdenum Nitride ◽  
X Ray Diffraction ◽  
Two Phase ◽  
X Ray ◽  
Liquid Spray ◽  
Average Size ◽  
Highly Porous ◽  
Calculated Average

ABSTRACTPolycrystalline, small grain sized, 15 μm thick MoxN (x=1 or 2) films, void of detectable concentrations of molybdenum oxides, have been prepared on 50 μm thick nitrided Ti substrates via conversion of precursor MoO3 films in a programmed reaction with NH3. The latter films were produced via liquid spray pyrolysis of an MoCl5/methanol mixture in air at 500° C. The reaction of MoO3 films with NH3 resulted in a two-phase MoxN mixture consisting of γ-Mo2N and δ-MoN. The change in density of MoO3(ρ=4.69 g/cm3) to γ-MoN (ρ=9.50 g/cm3) and δ-MoN (ρ=9.05 g/cm3) produced grains with a calculated average size of 10 nm without losing adherence to the substrate. The composition of the MoxN films was determined by X-ray diffraction (XRD) and Auger electron spectroscopy (AES) to be ∼ 60% γ-Mo2N and 40% δ-MoN. The results of scanning electron microscopy (SEM) showed the surface morphology of the MoxN films to be highly porous.

Effect of Shock Loading on the Microstructure of Uniloy 326

1974 ◽  
Vol 32 ◽  
pp. 504-505
Author(s):  
K. P. Staudhammer ◽  
L. E. Murr
Keyword(s):  
Grain Size ◽  
Shock Loading ◽  
Current Investigation ◽  
Two Phase ◽  
05 C ◽  
Shock Deformation ◽  
Heat Treated

The effect of shock loading on a variety of steels has been reviewed recently by Leslie. It is generally observed that significant changes in microstructure and microhardness are produced by explosive shock deformation. While the effect of shock loading on austenitic, ferritic, martensitic, and pearlitic structures has been investigated, there have been no systematic studies of the shock-loading of microduplex structures.In the current investigation, the shock-loading response of millrolled and heat-treated Uniloy 326 (thickness 60 mil) having a residual grain size of 1 to 2μ before shock loading was studied. Uniloy 326 is a two phase (microduplex) alloy consisting of 30% austenite (γ) in a ferrite (α) matrix; with the composition.3% Ti, 1% Mn, .6% Si,.05% C, 6% Ni, 26% Cr, balance Fe.

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