Numerical simulations on effects of oxygen concentration on the structure and soot formation in a two-dimensional axisymmetric laminar C2H4/(O2–CO2) diffusion flame

A theoretical investigation of the influence of a standing wave flow-field on the dynamics of a laminar two-dimensional spray diffusion flame is presented for the first time. The mathematical analysis permits mild slip between the droplets and their host surroundings. For the liquid phase, the use of a small Stokes number as the perturbation parameater enables a solution of the governing equations to be developed. Influence of the standing wave flow-field on droplet grouping is described by a specially constructed modification of the vaporization Damkohler number. Instantaneous flame front shapes are found via a solution for the usual Schwab–Zeldovitch parameter. Numerical results obtained from the analytical solution uncover the strong bearing that droplet grouping, induced by the standing wave flow-field, can have on flame height, shape, and type (over- or under-ventilated) and on the existence of multiple flame fronts.

Download Full-text

Towards explicit regulating-ion-transport: nanochannels with only function-elements at outer-surface

Nature Communications ◽

10.1038/s41467-021-21507-7 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Qun Ma ◽

Yu Li ◽

Rongsheng Wang ◽

Hongquan Xu ◽

Qiujiao Du ◽

...

Keyword(s):

Ion Transport ◽

Numerical Simulations ◽

Power Density ◽

Outer Surface ◽

Internal Resistance ◽

Porous Membranes ◽

Two Dimensional ◽

Ionic Selectivity ◽

Key Features ◽

Energy Conversion Devices

AbstractFunction elements (FE) are vital components of nanochannel-systems for artificially regulating ion transport. Conventionally, the FE at inner wall (FEIW) of nanochannel−systems are of concern owing to their recognized effect on the compression of ionic passageways. However, their properties are inexplicit or generally presumed from the properties of the FE at outer surface (FEOS), which will bring potential errors. Here, we show that the FEOS independently regulate ion transport in a nanochannel−system without FEIW. The numerical simulations, assigned the measured parameters of FEOS to the Poisson and Nernst-Planck (PNP) equations, are well fitted with the experiments, indicating the generally explicit regulating-ion-transport accomplished by FEOS without FEIW. Meanwhile, the FEOS fulfill the key features of the pervious nanochannel systems on regulating-ion-transport in osmotic energy conversion devices and biosensors, and show advantages to (1) promote power density through concentrating FE at outer surface, bringing increase of ionic selectivity but no obvious change in internal resistance; (2) accommodate probes or targets with size beyond the diameter of nanochannels. Nanochannel-systems with only FEOS of explicit properties provide a quantitative platform for studying substrate transport phenomena through nanoconfined space, including nanopores, nanochannels, nanopipettes, porous membranes and two-dimensional channels.

Download Full-text

Dynamical and pressure structures in winds with multiple embedded evaporating clumps - I. Two-dimensional numerical simulations

Monthly Notices of the Royal Astronomical Society ◽

10.1111/j.1365-2966.2005.09268.x ◽

2005 ◽

Vol 361 (3) ◽

pp. 1077-1090 ◽

Cited By ~ 52

Author(s):

J. M. Pittard ◽

J. E. Dyson ◽

S. A. E. G. Falle ◽

T. W. Hartquist

Keyword(s):

Numerical Simulations ◽

Two Dimensional

Download Full-text

Relation between the inhibition of the laminar diffusion flame of polymers, soot formation, and radiation

Combustion Explosion and Shock Waves ◽

10.1007/bf00750435 ◽

1983 ◽

Vol 19 (5) ◽

pp. 608-610

Author(s):

L. E. Makharinskii ◽

N. A. Khalturinskii ◽

Al. Al. Berlin ◽

T. A. Rudakova

Keyword(s):

Diffusion Flame ◽

Soot Formation ◽

Laminar Diffusion Flame ◽

Laminar Diffusion

Download Full-text

The Best Perturbation Method for the Parameter Inversion of Two-Dimension Convection-Diffusion Equation

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.380-384.1143 ◽

2013 ◽

Vol 380-384 ◽

pp. 1143-1146

Author(s):

Xiang Guo Liu

Keyword(s):

Inverse Problem ◽

Diffusion Equation ◽

Perturbation Method ◽

Numerical Simulations ◽

Numerical Solution ◽

Two Dimensional ◽

Convection Diffusion ◽

Convection Diffusion Equation ◽

Parameter Inversion ◽

Parametric Inversion

The paper researches the parametric inversion of the two-dimensional convection-diffusion equation by means of best perturbation method, draw a Numerical Solution for such inverse problem. It is shown by numerical simulations that the method is feasible and effective.

Download Full-text