An investigation of liquid film thickness during solutal Marangoni condensation using a laser absorption method: Absorption property and examination of measuring method

In this study, the atomization of heavy fuel oil (Mazut) and diesel fuel at different pressures is compared experimentally. Also, the effects of temperature on the Mazut fuel atomization are investigated experimentally. Mass flow rate, discharge coefficient, wavelength, liquid film thickness, ligament diameter, spray angle, breakup length, and sature mean diameter are obtained for the Mazut and diesel fuel. Fuels spray images at different pressures and temperatures are recorded using the shadowgraphy method and analyzed by the image processing technique. Error analysis is performed for the experiments, and the percentage of uncertainty for each parameter is reported. The experimental results are compared with the theoretical results. Also, Curves are proposed and plotted to predict changes in the behavior of atomization parameters. Diesel fuel has less viscosity than Mazut fuel. Diesel fuel has shorter breakup length, wavelength, liquid film thickness, and sature mean diameter than Mazut fuel at the same pressure. Diesel fuel has a larger spray angle and a larger discharge coefficient than Mazut fuel at the same pressure. As the pressure and temperature increase, fuel atomization improves. The viscosity of Mazut fuel is decreased by temperature increase. As the fuel injection pressure and temperature increase, breakup length, wavelength, liquid film thickness, and sature mean diameter decrease; also, spray angle increases.

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Liquid film thickness of two‐phase slug flows in capillary microchannels: A review paper

The Canadian Journal of Chemical Engineering ◽

10.1002/cjce.24068 ◽

2021 ◽

Author(s):

Amin Etminan ◽

Yuri S. Muzychka ◽

Kevin Pope

Keyword(s):

Film Thickness ◽

Liquid Film ◽

Review Paper ◽

Liquid Film Thickness ◽

Two Phase ◽

Slug Flows

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Measurement of Liquid Film Thickness in Micro Tube Annular Flow

2010 14th International Heat Transfer Conference, Volume 6 ◽

10.1115/ihtc14-23176 ◽

2010 ◽

Cited By ~ 1

Author(s):

Hiroshi Kanno ◽

Youngbae Han ◽

Yusuke Saito ◽

Naoki Shikazono

Keyword(s):

Heat Transfer ◽

Film Thickness ◽

Liquid Film ◽

Annular Flow ◽

Liquid Film Thickness ◽

Phase Flow ◽

Two Phase ◽

Micro Scale ◽

Film Model ◽

Annular Film

Heat transfer in micro scale two-phase flow attracts large attention since it can achieve large heat transfer area per density. At high quality, annular flow becomes one of the major flow regimes in micro two-phase flow. Heat is transferred by evaporation or condensation of the liquid film, which are the dominant mechanisms of micro scale heat transfer. Therefore, liquid film thickness is one of the most important parameters in modeling the phenomena. In macro tubes, large numbers of researches have been conducted to investigate the liquid film thickness. However, in micro tubes, quantitative information for the annular liquid film thickness is still limited. In the present study, annular liquid film thickness is measured using a confocal method, which is used in the previous study [1, 2]. Glass tubes with inner diameters of 0.3, 0.5 and 1.0 mm are used. Degassed water and FC40 are used as working fluids, and the total mass flux is varied from G = 100 to 500 kg/m2s. Liquid film thickness is measured by laser confocal displacement meter (LCDM), and the liquid-gas interface profile is observed by a high-speed camera. Mean liquid film thickness is then plotted against quality for different flow rates and tube diameters. Mean thickness data is compared with the smooth annular film model of Revellin et al. [3]. Annular film model predictions overestimated the experimental values especially at low quality. It is considered that this overestimation is attributed to the disturbances caused by the interface ripples.

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