Numerical simulation of liquid film formation and evaporation in dip coating

Steady-state fluorescence (SSF) technique in conjunction with UV-visible (UVV) technique and atomic force microscope (AFM) was used for studying film formation from TiO2covered nanosized polystyrene (PS) latex particles (320 nm). The effects of film thickness and TiO2content on the film formation and structure properties of PS/TiO2composites were studied. For this purpose, two different sets of PS films with thicknesses of 5 and 20 μm were prepared from pyrene-(P-) labeled PS particles and covered with various layers of TiO2using dip-coating method. These films were then annealed at elevated temperatures above glass transition temperature () of PS in the range of 100–280°C. Fluorescence emission intensity, from P and transmitted light intensity, were measured after each annealing step to monitor the stages of film formation. The results showed that film formation from PS latexes occurs on the top surface of PS/TiO2composites and thus developed independent of TiO2content for both film sets. But the surface morphology of the films was found to vary with both TiO2content and film thickness. After removal of PS, thin films provide a quite ordered porous structure while thick films showed nonporous structure.

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Numerical simulation of the liquid phase in SnO2 thin film deposition by sol-gel-dip-coating

Journal of Sol-Gel Science and Technology ◽

10.1007/s10971-010-2263-0 ◽

2010 ◽

Vol 55 (3) ◽

pp. 385-393 ◽

Cited By ~ 14

Author(s):

Dayene M. Carvalho ◽

Jorge L. B. Maciel ◽

Leandro P. Ravaro ◽

Rogério E. Garcia ◽

Valdemir G. Ferreira ◽

...

Keyword(s):

Thin Film ◽

Numerical Simulation ◽

Liquid Phase ◽

Sol Gel ◽

Thin Film Deposition ◽

Dip Coating ◽

Film Deposition ◽

Sno2 Thin Film

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NUMERICAL INVESTIGATION OF FILM DISTRIBUTION IN HORIZONTAL-TUBE FALLING FILM EVAPORATOR

International Journal of Air-Conditioning and Refrigeration ◽

10.1142/s2010132511000521 ◽

2011 ◽

Vol 19 (03) ◽

pp. 177-183 ◽

Cited By ~ 1

Author(s):

JIN-BO CHEN ◽

QING-GANG QIU

Keyword(s):

Numerical Simulation ◽

Fluid Flow ◽

Film Thickness ◽

Liquid Film ◽

Numerical Investigation ◽

Horizontal Tube ◽

Flow Density ◽

Falling Film ◽

Film Distribution ◽

Simulation Results

The technique of horizontal-tube falling film has been used in the cooling and heating industries such as refrigeration systems, heating systems and ocean thermal energy conversion systems. The comprehensive performance of evaporator is directly affected by the film distribution characteristics outside tubes. In this paper, numerical investigation was performed to predict the film characteristics outside the tubes in horizontal-tube falling film evaporator. The effects of liquid flow rate, tube diameter and the circular degree of tube on the film thickness were presented. The numerical simulation results were compared with that of the empirical equations for calculating the falling film thickness, and agreements between them were reasonable. Numerical simulation results show that, at the fixed fluid flow density, the liquid film is thicker on the upper and lower tube and the thinnest liquid film appears at angle of about 120°. The results also indicate that, when the fluid flow density decreases to a certain value, the local dryout spot on the surface of the tube would occur. In addition, the film thickness decreases with the increases of the tube diameter at the fixed fluid flow density.

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Synthesis and Characterization of TiO2/SiO2 Monoliths as Photocatalysts on Methanol Oxidation

International Journal of Photoenergy ◽

10.1155/2018/8478240 ◽

2018 ◽

Vol 2018 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Rigoberto Regalado-Raya ◽

Rubí Romero-Romero ◽

Osmín Avilés-García ◽

Jaime Espino-Valencia

Keyword(s):

Thin Film ◽

Methanol Oxidation ◽

Immersion Time ◽

Film Formation ◽

Anatase Phase ◽

Sol Gel ◽

Packed Bed ◽

Dip Coating ◽

Packed Bed Reactor ◽

Titanium Butoxide

Photocatalytic materials based on silica-titania (SiO2-TiO2) were synthesized by sol-gel and dip-coating method. TEOS and titanium butoxide were used as precursors of the silica-titania, respectively. A thin film with anatase phase was obtained on the surface of the support. The effect of variables as dispersion mechanism, immersion time, and number of treatment cycles were studied. The materials were characterized using X-ray diffraction, scanning electron microscopy, energy dispersion scanning, and N2 adsorption-desorption. The highest crystallinity of TiO2 on silica, high specific surface area in TiO2-SiO2 materials, and thin film formation were obtained by using a stirring plate and minimum immersion time. The so synthesized catalyst allowed the production of formaldehyde from the photocatalyzed methanol oxidation in a packed-bed reactor.

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Flow Characteristics of Liquid Films of Annular Two-Phase Flow in a Curved DoubleTube. Flow Rate of Liquid Film and Mechanism of Film Formation.

TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series B ◽

10.1299/kikaib.66.652_3189 ◽

2000 ◽

Vol 66 (652) ◽

pp. 3189-3195

Author(s):

Osamu WATANABE ◽

Shoji KURIYAMA

Keyword(s):

Liquid Film ◽

Flow Rate ◽

Two Phase Flow ◽

Film Formation ◽

Flow Characteristics ◽

Liquid Films ◽

Phase Flow ◽

Two Phase

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Lubricating oil film formation on the surface of a piston skirt in diesel engines. (Numerical simulation using the boundary element method)

TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series B ◽

10.1299/kikaib.52.3406 ◽

1986 ◽

Vol 52 (481) ◽

pp. 3406-3412 ◽

Cited By ~ 1

Author(s):

Toyohiko SUZUKI ◽

Yoshio FUJIMOTO ◽

Yoshitaka OCHIAI

Keyword(s):

Numerical Simulation ◽

Boundary Element Method ◽

Boundary Element ◽

Diesel Engines ◽

Film Formation ◽

Lubricating Oil ◽

Oil Film ◽

Piston Skirt ◽

Element Method

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Impingement characteristics of an early injection gasoline direct injection engine: A numerical study

International Journal of Engine Research ◽

10.1177/1468087416663325 ◽

2016 ◽

Vol 18 (4) ◽

pp. 378-393 ◽

Cited By ~ 7

Author(s):

Nicholas J Beavis ◽

Salah S Ibrahim ◽

Weeratunge Malalasekera

Keyword(s):

Liquid Film ◽

Film Formation ◽

Direct Injection ◽

Cylinder Liner ◽

Gasoline Direct Injection ◽

Intake Valve ◽

Direct Injection Engine ◽

Gasoline Direct Injection Engine ◽

Start Of Injection ◽

Early Injection

This article describes the use of a Lagrangian discrete droplet model to evaluate the liquid fuel impingement characteristics on the internal surfaces of an early injection gasoline direct injection engine. This study focuses on fuel impingement on the intake valve and cylinder liner between start of injection and 20° after start of injection using both a single- and a multi-component fuels. The single-component fuel used was iso-octane and the multi-component fuel contained fractions of iso-pentane, iso-octane and n-decane to represent the light, medium and heavy fuel fractions of gasoline, respectively. A detailed description of the impingement and liquid film modelling approach is also provided. Fuel properties, wall surface temperature and droplet Weber number and Laplace number were used to quantify the impingement regime for different fuel fractions and correlated well with the predicted onset of liquid film formation. Evidence of film stripping was seen from the liquid film formed on the side of the intake valve head with subsequent ejected droplets being a likely source of unburned hydrocarbons and particulate matter emissions. Differences in impingement location and subsequent location of liquid film formation were also observed between single- and multi-component fuels. A qualitative comparison with experimental cylinder liner impingement data showed the model to well predict the timing and positioning of the liner fuel impingement.

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