Semi-Empirical Correlation to Predict the Sauter Mean Diameter of the Pressure-Swirl Atomizer

Volume 1: Advances in Aerodynamics ◽

10.1115/imece2013-62907 ◽

2013 ◽

Author(s):

Wei Xiao ◽

Yong Huang

Keyword(s):

Weber Number ◽

Droplet Diameter ◽

Empirical Correlation ◽

Sauter Mean Diameter ◽

Operation Condition ◽

Wide Range ◽

Swirl Atomizer ◽

Pressure Swirl ◽

Semi Empirical ◽

Pressure Swirl Atomizer

In this study, experiments have been performed to investigate effects of pressure-swirl atomizer geometry on SMD. Different pressure-swirl atomizers were applied to study the effect of geometry on the SMD. Based on the experimental results, an empirical correlation was obtained to relate SMD with the Weber number characterized by film thickness. Meanwhile, a semi-empirical model which was improved from the surface wave breakup theory was established to predict the SMD of pressure-swirl atomizers. The model provides the droplet diameter as a function of atomizer geometry, operation condition and liquid properties. It is proved that the model is qualified for predicting SMD of pressure-swirl atomizers among wide range.

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A Numerical Approach for the Simulation of Internal Nozzle Flow in a Pressure Swirl Atomizer Using Different Turbulent Models and Towards an Effective Inlet Weber Number

Volume 7A: Fluids Engineering Systems and Technologies ◽

10.1115/imece2013-65627 ◽

2013 ◽

Author(s):

Ahmadreza Abbasi Baharanchi ◽

Seckin Gokaltun ◽

Shahla Eshraghi

Keyword(s):

Weber Number ◽

Computational Cost ◽

Internal Flow ◽

Numerical Approach ◽

Reynolds Stress Model ◽

Multiphase Model ◽

Vof Model ◽

Swirl Atomizer ◽

Pressure Swirl ◽

Pressure Swirl Atomizer

VOF Multiphase model is used to simulate the flow inside a pressure-swirl-atomizer. The capability of the Reynolds Stress Model and variants of the K-ε and K-ω models in modeling of turbulence has been investigated in the commercial computational fluid dynamics (CFD) software FLUENT 6.3. The Implicit scheme available in the volume-of-fluid (VOF) model is used to calculate the interface representation between phases. The atomization characteristics have been investigated as well as the influence of the inlet swirl strength of the internal flow. The numerical results have been successfully validated against experimental data available for the computed parameters. The performance of the RNG K-ε model was found to be satisfactory in reducing the computational cost and introducing an effective Weber number for the flow simulated in this study.

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Internal flow characteristics in scaled pressure-swirl atomizer

EPJ Web of Conferences ◽

10.1051/epjconf/201818002059 ◽

2018 ◽

Vol 180 ◽

pp. 02059 ◽

Cited By ~ 1

Author(s):

Milan Malý ◽

Marcel Sapík ◽

Jan Jedelský ◽

Lada Janáčková ◽

Miroslav Jícha ◽

...

Keyword(s):

High Speed ◽

Laser Doppler Anemometry ◽

Flow Characteristics ◽

Internal Flow ◽

Liquid Sheet ◽

Wide Range ◽

Swirl Atomizer ◽

Pressure Swirl ◽

Pressure Swirl Atomizer ◽

Working Liquid

Pressure-swirl atomizers are used in a wide range of industrial applications, e.g.: combustion, cooling, painting, food processing etc. Their spray characteristics are closely linked to the internal flow which predetermines the parameters of the liquid sheet formed at the discharge orifice. To achieve a better understanding of the spray formation process, the internal flow was characterised using Laser Doppler Anemometry (LDA) and high-speed imaging in a transparent model made of cast PMMA (Poly(methyl methacrylate)). The design of the transparent atomizer was derived from a pressure-swirl atomizer as used in a small gas turbine. Due to the small dimensions, it was manufactured in a scale of 10:1. It has modular concept and consists of three parts which were ground, polished and bolted together. The original kerosene-type jet A-1 fuel had to be replaced due to the necessity of a refractive index match. The new working liquid should also be colourless, non-aggressive to the PMMA and have the appropriate viscosity to achieve the same Reynolds number as in the original atomizer. Several liquids were chosen and tested to satisfy these requirements. P-Cymene was chosen as the suitable working liquid. The internal flow characteristics were consequently examined by LDA and high-speed camera using p-Cymene and Kerosene-type jet A-1 in comparative manner.

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Experimental and Analytical Investigation on the Variation of Spray Characteristics Along Radial Distance Downstream of a Pressure Swirl Atomizer

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.3239932 ◽

1986 ◽

Vol 108 (3) ◽

pp. 473-478 ◽

Cited By ~ 4

Author(s):

Y. H. Zhao ◽

W. M. Li ◽

J. S. Chin

Keyword(s):

Drop Size ◽

Laser Light ◽

Radial Distance ◽

Analytical Investigation ◽

Laser Light Scattering ◽

Sauter Mean Diameter ◽

Spray Characteristics ◽

Swirl Atomizer ◽

Pressure Swirl ◽

Pressure Swirl Atomizer

The variation of spray characteristics (Sauter Mean Diameter and Rosin-Rammler drop-size distribution parameter) downstream of a pressure swirl atomizer along radial distance has been measured by laser light scattering technology. An analytical model has been developed that is capable of predicting the variation of spray characteristics along radial distance. A comparison between the prediction and experimental data shows excellent agreement. It shows that the spray model proposed, although relatively simple, is correct and can be used with some expansion and modification to predict more complicated spray systems.

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A Computational Fluid Dynamics-based Correlation to Predict Droplet Sauter Mean Diameter for Σ− Yliq Atomization Model in Pressure Swirl Atomizer

European Journal of Engineering and Technology Research ◽

10.24018/ej-eng.2021.6.7.2645 ◽

2021 ◽

Vol 6 (7) ◽

pp. 69-76

Author(s):

Sherry K. Amedorme ◽

Joseph Apodi

Keyword(s):

Fluid Dynamics ◽

Fuel Injection ◽

Liquid Velocity ◽

Operating Conditions ◽

Sauter Mean Diameter ◽

Design Variables ◽

Mean Diameter ◽

Swirl Atomizer ◽

Pressure Swirl ◽

Pressure Swirl Atomizer

Liquid atomization is crucial to ensure efficient combustion as it is an inherent part of the injector system. The combustion of fuels relies on effective atomization to increase the surface area of the fuel and consequently achieve high rates of mixing and evaporation. Pressure swirl atomizers are inexpensive and reliable type of atomizer for fuel injection owing to its superior atomization characteristics and relatively simple geometry. The Sauter mean diameter (SMD) of atomizer contributes significantly to the combustion chamber performance. This paper presents a two-step strategy to predict droplet SMD for atomisation model in pressure swirl atomizer through the combination of experimentally validated Computation Fluid Dynamics (CFD) and Optimal Latin Hypercubes (OLHC) Design of Experiments (DoE) techniques. A three-dimensional Eulerian two-phase CFD model is developed to account for liquid and gas phases as a single continuum with high-density variation at large Reynolds and Weber numbers and validated against experimental measurements, before being employed to carry out a parametric study involving operating conditions and fluid properties of the pressure swirl atomizer. The atomizer is then represented in terms of four design variables, namely liquid viscosity, liquid velocity, surface tension and atomizer exit diameter. An 87-point OLHC DoE is constructed within the design variables space using a permutation genetic algorithm resulting in an accurate SMD prediction. Results show the newly developed SMD prediction is found to be superior compared with existing correlations and indicate significant improvement in the droplets SMD.

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