Studies on transfer processes in mixing vessels: effect of gas on solid-liquid hydrodynamics using modified Rushton turbine agitators

1997 ◽  
Vol 17 (1) ◽  
pp. 55 ◽  
Author(s):  
R. V. Roman ◽  
R. Z. Tudose
Keyword(s):  
Rushton Turbine ◽  
Transfer Processes ◽  
Mixing Vessels ◽  
Solid Liquid

Thermohydrodynamic Analysis of Solid-Liquid Lubricated Journal Bearings

1988 ◽  
Vol 110 (2) ◽  
pp. 367-374 ◽  
Author(s):  
M. M. Khonsari ◽  
V. Esfahanian
Keyword(s):  
Journal Bearing ◽  
Journal Bearings ◽  
Solid Particles ◽  
Governing Equations ◽  
Transfer Processes ◽  
Flow And Heat Transfer ◽  
Experimental Findings ◽  
Solid Liquid ◽  
General Computer Program ◽  
Good Agreement

Thermohydrodynamic theory is extended to include the effect of solid particles in hydrodynamically lubricated journal bearings. Appropriate governing equations and boundary conditions are derived for the fluid flow and heat transfer processes taking place in a finite journal bearing. A general computer program is developed to numerically solve the governing equations. Results are provided for biphase lubricants containing oil with molybdenum disulfide and polytetrafluoroethylene particles. The computational results are in good agreement with experimental findings. The results indicate that the bearing temperature field is affected significantly by the presence of particles in oil. Moreover, it is found that inclusion of particles in the lubricant results in a higher coefficient of friction in the mid-range of the Sommerfeld number compared to that of the clean oil.

Agitation of a gas-solid-liquid system in a vessel with high-speed impeller and vertical tubular coil

2012 ◽  
Vol 66 (6) ◽  
Author(s):  
Marta Major-Godlewska ◽  
Joanna Karcz
Keyword(s):  
Power Consumption ◽  
High Speed ◽  
Gas Bubbles ◽  
Liquid System ◽  
Specific Power ◽  
Specific Power Consumption ◽  
Rushton Turbine ◽  
Agitated Vessel ◽  
Solids Concentration ◽  
Solid Liquid

AbstractExperimental results of gas hold-up, power consumption and residence time of gas bubbles in a gas-solid-liquid system produced in an agitated vessel equipped with a high-speed impeller and a vertical tubular coil are presented in this paper. Critical agitator speed, needed for the dispersion of gas bubbles and solid particles in liquid were also identified. The studies were carried out in an agitated vessel of the inner diameter D = 0.634 m and the working liquid volume of about 0.2 m3. A tubular coil of the diameter of 0.7D, consisting of 24 vertical tubes of the diameter of 0.016D, was located inside the flat-bottomed vessel. The agitated vessel was equipped with a Rushton turbine with six blades or an A 315 impeller with four blades. Both impellers had diameter, d, equal to 0.33D. The vessel was filled with liquid up to the height H = D. In this study, air and particles of sea sand with the mean diameter of 335 μm and the concentration of up to 3.0 mass % were dispersed in distilled water as the liquid phase. The measurements were carried out within the turbulent regime of the fluid flow in the agitated vessel. Results of the measurements were processed graphically and mathematically. Lower values of the critical agitator speed, n JSG, needed for simultaneous dispersion of gas bubbles and particles with the solids concentration from 0.5 mass % to 2 mass %, were obtained for the vessel equipped with the A 315 impeller. Higher values of the specific power consumption were reached for the vessel with the Rushton turbine. Higher values of the gas hold-up and residence time of the gas bubbles in the fluid were obtained for the system equipped with the Rushton turbine. Results of the gas hold-up as a function of the specific power consumption, superficial gas velocity and solids concentration were approximated with good accuracy using Eq. (5).

scholarly journals Intensification of the mass transfer processes in the system “solid-liquid” by use of inert gas

2019 ◽  
Author(s):  
Jaroslaw Gumnitsky ◽  
Volodymyr Atamaniuk ◽  
Vira Sabadash ◽  
Liubov Venger
Keyword(s):  
Mass Transfer ◽  
Inert Gas ◽  
Transfer Processes ◽  
Mass Transfer Processes ◽  
Solid Liquid

scholarly journals Influence of Parameters in Coal Water Slurry Mixing used for Gasification in Power Plant

2020 ◽  
Vol 9 (1) ◽  
pp. 1321-1329
Keyword(s):  
Power Plant ◽  
Energy Efficient ◽  
Past Research ◽  
Mechanical Mixing ◽  
Mixing Energy ◽  
Water Slurry ◽  
Coal Water Slurry ◽  
Mixing Vessels ◽  
Solid Liquid

This research analyses, updates and extends the concept of agitation used in mixing energy efficient systems. It also focuses on stirring processes that specifically affect solid-liquid particulate phases that are permitted in automated mechanical mixing vessels which is jacketed The major principle points of agitation utilizing mixed vessels is to keep up adjusted amounts of substances in various stages dependent on concentration. In situations where dissolvable solids are blended, stirrers are utilized to expand communication between the solid crystals and continue a strategic distance from lopsided gathering at a certain point. Therefore, this evaluate article is to fundamentally examine the various parts of past research works revealed in the field of solid-fluid strong blending.

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