Novel Membrane Bioreactor with Gas/Liquid Two-Phase Flow for High-Performance Degradation of Phenol

1998 ◽  
Vol 14 (5) ◽  
pp. 680-688 ◽  
Author(s):  
D. Leonard ◽  
M. Mercier-Bonin ◽  
N.D. Lindley ◽  
C. Lafforgue
Keyword(s):  
High Performance ◽  
Membrane Bioreactor ◽  
Two Phase Flow ◽  
Performance Degradation ◽  
Phase Flow ◽  
Two Phase

Influences of Impeller Diameter and Diffuser Blades on Air-Water Two-Phase Flow Performance of Centrifugal Pump

2005 ◽  
Author(s):  
Naoki Matsushita ◽  
Akinori Furukawa ◽  
Kusuo Okuma ◽  
Satoshi Watanabe
Keyword(s):  
Centrifugal Pump ◽  
Water Flow ◽  
Flow Rate ◽  
Rotational Speed ◽  
Flow Condition ◽  
High Performance ◽  
Two Phase Flow ◽  
Water Flow Rate ◽  
Phase Flow ◽  
Two Phase

A tandem arrangement of double rotating cascades and single diffuser cascade, proposed as a centrifugal pump with high performance in air-water two-phase flow condition, yields lower head due to the smallness of the impeller outlet in comparison with a impeller with large outlet diameter and no diffuser. Influences of impeller diameter change and installation of diffuser blades on two-phase flow performance were experimentally investigated under the case of the same volute casing. As the result, the similarity law of the diameter of impeller having the similar blade geometry and the rotational speed is satisfied even in two-phase flow condition. Comparing pump performances between a large impeller without diffuser blades and a small one with diffuser blades, higher two-phase flow performance is obtained by controlling the rotational speed of a small impeller with diffuser blades in the range of small water flow rates, while a large impeller with no diffuser gives high performance in the range of high water flow rate and small air flow rate.

Boiling and Two-Phase Flow in Channels With Extremely Small Dimensions: Review of Japanese Research

2004 ◽  
Author(s):  
Haruhiko Ohta
Keyword(s):  
High Performance ◽  
Two Phase Flow ◽  
Waste Heat ◽  
Narrow Channel ◽  
Phase Flow ◽  
Parallel Plates ◽  
Two Phase ◽  
Practical Applications ◽  
Ideal System ◽  
Mini Channels

Researches concerning micro actuators utilizing vapor-liquid interfacial phenomena are extensively investigated to develop thermal devices applied to micro machines. On the other hand, the application of two-phase flow is useful for the removal of waste heat from the semiconductor chips with highly increased heat generation density to be integrated in notebook PCs. In the present paper, the latest Japanese research on boiling and two-phase flow in mini channels is reviewed covering those for the fundamental phenomena and practical applications. Boiling in a narrow channel between parallel plates is an ideal system for the development of the high-performance heat exchangers with extremely small sizes. The promising approaches to increasing the critical heat flux are introduced those by the present author to compensate the disadvantage inherent in this system.

scholarly journals Program for determination of zones of gold concentration on sluices of washing devices

2021 ◽  
Vol 895 (1) ◽  
pp. 012002
Author(s):  
V S Alekseev ◽  
R S Seryi
Keyword(s):  
High Performance ◽  
Two Phase Flow ◽  
Experimental Studies ◽  
Operating Conditions ◽  
Phase Flow ◽  
Technological Parameters ◽  
Two Phase ◽  
Alluvial Gold ◽  
Wide Range ◽  
Host Rocks

Abstract Currently sluice washing devices are the most common in alluvial gold mining. Their use provides a sufficiently high performance, relatively low power consumption, and acceptable recovery of valuable components. The theoretical provisions of traditional hydraulics make it possible to determine all the main parameters of the movement of particles of rocks and gold in the pulp, however, in real operating conditions of the sluice box, their actual values will differ greatly from the calculated ones, especially if there are solid fractions in the pulp with a particle size of more than 20 mm. This is explained by significant fluctuations in the values of the surface, average and bottom velocities of the two-phase flow, vertical pulsation velocity in conditions of constrained movement of the different fractional composition of rocks. The article presents the results of experimental studies to identify the dependence of the distance traveled by an individual gold particle and host rocks in a two-phase flow through a sluice, the bottom of which is lined with trapping coatings, on the design and technological parameters of the flushing device. The mathematical model for determining this distance formed the basis of the Gold Enriching program. The program allows, in a wide range of initial data, to determine the zones of concentration of gold of a certain size at the sluice boxes.

scholarly journals Experimental Investigations on the Inner Flow Behavior of Centrifugal Pumps under Inlet Air-Water Two-Phase Conditions

Energies ◽  
2019 ◽  
Vol 12 (22) ◽  
pp. 4377 ◽  
Author(s):  
Si ◽  
Zhang ◽  
Bois ◽  
Zhang ◽  
Cui ◽  
...  
Keyword(s):  
Two Phase Flow ◽  
Flow Behavior ◽  
Bubbly Flow ◽  
Performance Degradation ◽  
Phase Flow ◽  
Centrifugal Pumps ◽  
Two Phase ◽  
Impeller Blade ◽  
Pump Performance ◽  
Starting Point

Centrifugal pumps are widely used and are known to be sensitive to inlet air-water two-phase flow conditions. The pump performance degradation mainly depends on the changes in the two-phase flow behavior inside the pump. In the present paper, experimental overall pump performance tests were performed for two different rotational speeds and several inlet air void fractions (αi) up to pump shut-off condition. Visualizations were also performed on the flow patterns of a whole impeller passage and the volute tongue area to physically understand pump performance degradation. The results showed that liquid flow modification does not follow head modification as described by affinity laws, which are only valid for homogeneous bubbly flow regimes. Three-dimensional effects were more pronounced when inlet void fraction increased up to 3%. Bubbly flow with low mean velocities were observed close to the volute tongue for all αi, and returned back to the impeller blade passages. The starting point of pump break down was related to a strong inward reverse flow that occurred in the vicinity of the shroud gap between the impeller and volute tongue area.

The Portable Computer System of Wet Gas Two-Phase Flow Measurement Based on Labview

2011 ◽  
Vol 328-330 ◽  
pp. 1968-1972
Author(s):  
Ying Xu ◽  
Ruo Shun Ma ◽  
Chun Ming Fu
Keyword(s):  
Computer System ◽  
High Performance ◽  
Two Phase Flow ◽  
High Reliability ◽  
Signal Acquisition ◽  
Phase Flow ◽  
Two Phase ◽  
Precision Data ◽  
Wet Gas ◽  
The Individual

In order to measure the individual flow rate of gas and liquid of wet gas two-phase flow without separation on line in situ.a computer system for metering wet gas based on labview has been developed. In this system, a high-performance embedded computer as the core unit has been used. Meanwhile, it consists of an industrial hard disk with wide temperature,a high precision data acquisition module, an industrial 12 inch LCD with wide temperature range, a group of rechargeable lithium battery and so on. The software platform is based on labview, which can achieve signal acquisition, calculate the gas and liquid transient flowrates, display and store data, etc. The application in industrial field shows that computer system developed here has good man-machine interaction interface, high reliability and other advantages.

Influence of Blade Pitch and Number of Blades of a Pump Inducer on Single and Two-Phase Flow Performance

2020 ◽  
Author(s):  
Michael Mansour ◽  
Trupen Parikh ◽  
Dominque Thévenin
Keyword(s):  
High Performance ◽  
Two Phase Flow ◽  
Low Flow ◽  
Phase Flow ◽  
Flow Conditions ◽  
Two Phase ◽  
Phase Mixing ◽  
Part Load ◽  
Two Phases ◽  
Load Conditions

Abstract This study investigates the influence of various inducer configurations upstream of a pump impeller on the single and two-phase flow performance. Three pitch values (P = 0.151, 0.251, and 0.351 m), as well as three different numbers of blades (N = 2, 3, and 4 blades), were studied, leading to a total of 9 different inducer geometries. The main objective of the present study is to analyze and compare the corresponding performances and the two-phase mixing behavior, which is necessary for improving the two-phase pumping ability. 3D steady-state simulations using the Moving Reference Frame (MRF) approach were applied for single-phase flow, while a transient setup using a moving-mesh approach was employed for two-phase simulations. Turbulence was modeled by the Reynolds Stress Model (RSM), whereas the Volume of Fluid (VOF) method was applied to model air-water interactions. The results show that the increase in the number of blades leads to a high performance drop at overload (high-flow) conditions, but only to a slight performance enhancement at part-load (low-flow) conditions. Additionally, the effective flow range of the inducer corresponding to high efficiency becomes narrower for a higher number of blades. Concerning the inducer pitch, at part-load conditions, a lower pitch is slightly beneficial to smoothly suck the flow and damp the low-flow vortices; employing a high pitch at these conditions results in intensified flow vortices, reducing slightly the performance. On the other hand, the blade pitch is very influential for the performance at optimal and overload conditions, where a lower pitch causes flow blockage, leading to significant performance deterioration and a very limited range of applications. Generally, it was found that a modification of the inducer configuration affects the performance much more at overload compared to part-load conditions. Concerning two-phase mixing performance, the highest pitch provides the best mixing since the inducer is able to effectively churn the two phases. Similarly, an increase in the number of blades amplifies the turbulence between the two phases, thus improving mixing. Overall, a higher inducer pitch and a low to moderate number of inducer blades best ensure high performance, wide working range, and efficient two-phase mixing.

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