Effect of Pressure Drop and Tangential Velocity on Vane Angle in Uniflow Cyclone

Compound hydrocyclone is an important separation equipment in oilfield waste water treatment. In order to grasp the equipment separation characteristics, its pressure field and production ability research is becoming more and more important. In the process of pressure or pressure drop deduced, the hydrocyclone’s vortex field is divided into two parts: semi-free vortex area and compulsive vortex area. In the free vortex area, the pressure and the pressure drop are all deduced by the tangential equation, the pressure gradient equation and the relationship equation of tangential velocity in the hydrocyclone body and the velocity of the rotary crib. In the compulsive vortex area, the pressure and the pressure drop are deduced by the velocity equation and the hydrocyclone’s separation equation. As to the respect of the production ability, it is fixed on the relationship of the inlet flow-rate, overflow pipe diameter, the main diameter of the compound hydrocyclone, pressure drop and the inlet liquid density. The research indicates that the pressure or the pressure drop are all connected with compound hydrocyclone’s diameter, rotary crib’s running velocity and diameter of the maximum tangential velocity track face. As the results of the research, the ascertained key operators, pressure and the pressure drop, the hydrocyclone’s production ability can provide designing consult for the hydrocyclone designers.

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CFD Analysis on Effect of Pressure Drop and Flow Uniformity with Geometry in 13“ Asymmetric DPF

Transactions of the Korean hydrogen and new energy society ◽

10.7316/khnes.2020.31.6.614 ◽

2020 ◽

Vol 31 (6) ◽

pp. 614-621

Author(s):

DANBEE HAN ◽

HYUNSEUNG BYUN ◽

YOUNGSOON BAEK

Keyword(s):

Pressure Drop ◽

Cfd Analysis ◽

Flow Uniformity ◽

Effect Of Pressure

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The effect of pressure drop stabilization in arteries during variations in blood flow rate

Acta Physiologica Scandinavica ◽

10.1111/j.1748-1716.1993.tb09559.x ◽

1993 ◽

Vol 148 (3) ◽

pp. 285-294 ◽

Cited By ~ 4

Author(s):

V. M. KHAYUTIN ◽

V. P. NIKOLSKY ◽

A. N. ROGOZA ◽

E. V. LUKOSHKOVA

Keyword(s):

Blood Flow ◽

Pressure Drop ◽

Flow Rate ◽

Blood Flow Rate ◽

Effect Of Pressure

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Numerical Flow Simulation of Spacer Grids With Mixing Vanes in a 5 × 5 PWR Rod Bundle

Volume 5: Fuel Cycle and High and Low Level Waste Management and Decommissioning; Computational Fluid Dynamics (CFD), Neutronics Methods and Coupled Codes; Instrumentation and Control ◽

10.1115/icone17-75354 ◽

2009 ◽

Cited By ~ 1

Author(s):

Moyse´s Alberto Navarro ◽

Andre´ Augusto Campagnole dos Santos

Keyword(s):

Heat Transfer ◽

Pressure Drop ◽

Pressure Loss ◽

Considerable Increase ◽

Local Heat Transfer ◽

Local Heat ◽

Spacer Grid ◽

Spacer Grids ◽

Rod Bundle ◽

Vane Angle

The spacer grids exert great influence on the thermal hydraulic performance of the PWR fuel assembly. The presence of the spacers has two antagonistic effects on the core: an increase of pressure drop due to constriction on the coolant flow area and increase of the local heat transfer downstream the grids caused by enhanced coolant mixing. The mixing vanes, present in most of the spacer grid designs, cause a cross and swirl flow between and in the subchannels, enhancing even more the local heat transfer at the cost of more pressure loss. Due to this important hydrodynamic feature the spacer grids are often improved aiming to obtain an optimal commitment between pressure drop and enhanced heat transfer. In the present work, the fluid dynamic performance downstream a 5 × 5 rod bundle with spacer grids is analyzed with a commercial CFD code (CFX 11.0). Eleven different split vane spacer grids with angles from 16° to 36° and a spacer without vanes were evaluated. The computational domain extends from ∼10 Dh upstream to ∼50 Dh downstream the spacer grids. The standard k-ε turbulence model with scalable wall functions and the total energy model were used in the simulations. The results show a considerable increase of the average Nusselt number and secondary mixing with the angle of the vane up to ∼20 Dh downstream the spacer, reducing greatly the influence of the vane angle beyond this region. As expected, the pressure loss through the spacer grid also showed considerable increase with the vane angle.

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Study on Characteristics and Operating Parameters of Axial Rotating Hydrocyclone

Volume 4: Ocean Engineering; Ocean Renewable Energy; Ocean Space Utilization, Parts A and B ◽

10.1115/omae2009-79114 ◽

2009 ◽

Author(s):

Yan Xu ◽

Zunce Wang ◽

Fengxia Lv ◽

Sen Li

Keyword(s):

Pressure Drop ◽

Laboratory Experiments ◽

Separation Efficiency ◽

Rotation Speed ◽

Tangential Velocity ◽

Flow Characteristics ◽

Internal Flow ◽

Axial Rotation ◽

Rotating Wall ◽

Simulation Results

The axial rotation of the hydrocyclone affects its internal flow characteristics and separating effect directly, as some local applications require the static hydrocyclone rotates about its own axis. Based on CFD, velocity distribution in the axial rotating hydrocyclone is studied. It is shown that as the rotation speed increasing, the tangential velocity improves and its gradient reduces in free vortex region observably, while the radial velocity has an incremental trend in the section of the small cone. The laboratory experiments are carried out for the static hydrocyclone of disposal capacity of 4 m3/h at 100r/min ∼ 300r/min. The relationships among rotation speed, flowrate, pressure drop and separated efficiency are achieved, which agree well with the numerical simulation results. The results indicate that the disposal capacity of hydrocyclone subjected to the rotation wall can be more flexible than that with no-rotating wall, the scope of best disposal capacity gradually enlarges with the increase of rotation speed of wall. Appropriate rise of the rotation speed is favor of the separation efficiency at the steady flowrate, however the increase of the flowrate and rotation speed induces the growth of the hydrocyclone’s pressure drop correspondingly to some extent.

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Experimental Study on Flow Patterns and Pressure Drop of Decaying Swirling Gas-Liquid Flow in a Vertical Pipe

Volume 1: Beyond Design Basis; Codes and Standards; Computational Fluid Dynamics (CFD); Decontamination and Decommissioning; Nuclear Fuel and Engineering; Nuclear Plant Engineering ◽

10.1115/icone2020-16484 ◽

2020 ◽

Author(s):

Jiarong Zhang ◽

Li Liu ◽

Shuai Liu ◽

Hanyang Gu

Keyword(s):

Pressure Drop ◽

Flow Regime ◽

Liquid Flow ◽

High Speed ◽

Phase Distribution ◽

Swirling Flow ◽

Tangential Velocity ◽

High Speed Camera ◽

Vertical Pipe ◽

Gas Liquid Flow

Abstract Vertical swirling gas-liquid flow is a kind of complex two-phase flow containing a nonzero tangential velocity component in engineering applications. The accurate flow regime characterization, phase distribution information and pressure drop data about vertical swirling flow are the basis for the optimization of steam generator (SG), which can greatly reduce the cost and improve the safety of nuclear plants. To get these key parameters of swirling vertical flow, we have made a comprehensive visualization experiment in a vertical pipe with 30mm diameter and 5m length by high-speed camera. The experimental pipe is separated into swirling part and non-swirling part. We have set three observation section with different vertical heights in the swirling part. Changing the flow rate of water and gas, different swirling flow pattern photos can be captured by high-speed camera. Based on the photos of different positions and image-processing MATLAB code, we can get three flow regime maps and figure out the decaying law of swirling gas-liquid flow. The pressure drop can be recorded by rotameter at each position. The decaying law of pressrure drop can be concluded from it. These data can be a guide for designing gas-liquid separator in SG to improve the efficiency of nuclear plant.

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