In this work, CFD simulations have been conducted to investigate flow behaviour of water in fully baffled stirred tank with Rushton turbine as impeller. The aim the paper is develop model...

Agitating liquids in an unbaffled surface aeration tank leads to the formation of a vortex region impeller shaft.The types and characteristics govern process phenomena tank.In present work, experimental results empirical correlations have been obtained relate depth number physical factors.Experiments carried out on geometrically similar systems, so that can be simulated field conditions.The critical speed at which reaches has estimated.It is found around speed, there observable change mass...

Abstract. Space for water is now becoming guiding principle of urban planning because flooding the major problem facing by most cities in India. Urban development developing countries like India usually occurs with high population concentrating small areas, poor drainage conditions. People occupy floodplain areas low flood years and when larger it causes damage. The origin floods floodplains encroachment unplanned systems. Complexities environment infrastructure have an inherent influence on...

Abstract BACKGROUND: The hydrodynamic conditions of a surface aeration system can be characterized by interpreting the power consumption impeller. Power consumed tanks depends on geometries impeller and tank, which is generally denoted number. RESULTS: various geometric dynamic parameters affecting number have been studied experimentally. Three flat‐bottomed cylindrical 1, 0.518 0.168 m 2 cross sectional area, fitted with six flat bladed impellers were used as baffled unbaffled circular...

Surface aeration systems employed in activated sludge plants are the most energy‐intensive units of and typically account for a higher percentage treatment facility’s total energy use. The geometry tank imparts major effect on system efficiency. It is said that at optimal geometric conditions, exhibits maximum Thus quantification conditions surface tanks needed. Optimal also needed to scale up laboratory result field installation. In present work, experimental studies have been carried out...

The difficulties associated with the use of standard LES (Large Eddy Simulation) models, particularly in near-wall regions, has lead to development hybrid models that attempt combine best aspects RANS (Reynolds Averaged Navier Stokes) and methodologies a single solution strategy. An example technique is detached-eddy simulation (DES). In this paper, application DES model made analysis turbulent flow generated impeller driven (Rushton Impeller) stirred tank reactor order understand behavior...

Abstract Surface aeration experiments were conducted in tanks of length to width ratio (L/W) 1.0, 1.5 and 2 as well circular study their relative performance on oxygen transfer energy consumption while re-aerating deoxygenated water. An identical geometric similarity various linear dimensions aerators, rotor blades diameter was maintained for all sizes shapes tested. The power consumed per unit volume concept simulate the coefficient k found be valid three aerators. Simulation equations...

This study explores the influence of varied stacking configurations in microbial fuel cells (MFCs) to channel acidogenic metabolism for enhanced bioelectricity generation, value-added acid synthesis, and wastewater treatment.

Surface aeration systems are the most energy extensive unit. It is essential that design of should be as near optimal possible. Here, geometry tank imparts a major effect on system efficiency. Therefore, it to have geometric conditions for tank. Optimal also needed scale up laboratory result field installation. In present work, experimental and numerical studies been carried out parameters oxygen transfer macromixing time in baffled circular surface ascertain conditions. developed work may...

Double- to single-loop pattern transition and a significant reduction in the power number with decrease clearance of Rushton turbine impeller baffled reactor was elucidated earlier research works. The present work investigates physical reasons behind these phenomena using computational fluid dynamics approach. Reynolds Averaged Navier–Stokes equations standard turbulence model closure were used turbulent flow conditions vessels. Multiple Reference Frame (MRF) approach adopted baffle...

The present study predicts the periodic behavior of mean velocity fields from properly verified and validated CFD model to determine extent vortex turbulent activity in a baffled tank stirred by standard six bladed Rushton Turbine. This region includes most action that controls mixing mass transfer processes tank. complexity periodicity radial tangential velocities direction axial is used fix proper as well extents generated RT. flow configuration confined within cylindrical around impeller...

Computational Fluid Dynamics (CFD) model for Rushton Turbine (RT) stirred tanks has been developed. The CFD validated with experimental (RPT) data. RPT data were calibrated Laser Doppler Anemometry (LDA) from literature. calibration of setup was done in two conditions: (a) stationary rotor and (b) rotating at 200 rpm. radiation intensity recorded measurement analysed by Analysis Variance (ANOVA) test found that counts have statistically equal mean. Also, the percentage error between mean is...

Abstract Earlier research works have elucidated that decrease in the clearance of Rushton Turbine (RT) impeller baffled reactor vessel causes a transition from double loop pattern to single with significant reduction power number. We observe similar flow behaviour when diameter is increased standard conditions vessel. The mean and turbulent fields associated vessels various agitated using RT were analysed Computational Fluid Dynamics technique so as understand hydrodynamic reasons causing...

The oxygen transfer rate is a parameter that characterizes the gas-liquid mass in surface aerators.Gas-liquid mechanisms aeration tanks depend on two different extreme lengths of time; namely, macromixing and micromixing.Small scale mixing close to molecular level referred as micromixing; whereas, refers large scale.Using experimental data numerical simulations, macro-and micro-scale parameters describing time scales were investigated.A up equation simulate with micromixing times was...