Investigation of Effects of Baffle Configuration on the Performance of a Fixed-Cone Valve by Gas-Liquid Two-Phase Model

2012 ◽  
Vol 166-169 ◽  
pp. 1824-1829
Author(s):  
W.L. Wei ◽  
B. Lv ◽  
Y.L. Liu ◽  
X.F. Yang

Nested type Fixed-Cone Valve, numerical simulation, energy dissipating, turbulent flow Abstract: In this paper, In this paper, a new type of Fixed-Cone Valve was proposed by improving the conventional type Fixed-Cone Valve .The flow fields of the two kinds of Fixed-Cone Valves were studied by using numerical simulation method .The computed pressure fields and the velocity fields were analyzed ,which shows that under the same conditions ,and by using the nested Fixed-Cone valve, the pressure of the upstream pipe and the cone valve and the average velocity along the downstream pipeline are reduced ,but the rate of energy dissipation is increased.

2012 ◽  
Vol 178-181 ◽  
pp. 429-432
Author(s):  
Y. L. Liu ◽  
B. Lv ◽  
W.L. Wei

In this paper, the flow structure of the oxidation ditch was studied using numerical simulation method and different submerged depth of aeration impellers. The computed velocity fields were analyzed, which shows that under the same conditions, and by using the optimal submerged depth the average velocity of the flow in oxidation ditch is increased and the velocity near-bottom has increased significantly. The results of comparisons show that the velocity distribution is more uniform along the depth direction, and that the flow velocity distribution structure can prevent sludge from settling in the oxidation ditch processing system at the submergence ratio called the optimal submergence ratio, which helps to improve the efficiency of oxidation ditch sewage treatment system.


2013 ◽  
Vol 694-697 ◽  
pp. 555-559
Author(s):  
Ji Hai Duan ◽  
Xing Xing Guan

Through the numerical simulation method, the Reynolds stress turbulence model (RSM) was used to simulate the flow field of circumfluent cyclone separator with three different outer chamber heights. Three circumfluent cyclones (CFC), with different outer chamber heights, are compared with each other. Pressure fields, velocity fields and pressure drop have been investigated. The results show that in a certain range, the outer chamber height of circumfluent cyclone separator has an optimum value, which can have higher separate efficiency and lower pressure drop. This provides a strong theoretical basis for the local optimization design of the cyclone.


2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Zhengzhi Wang ◽  
Chunling Zhu

In view of the rotor icing problems, the influence of centrifugal force on rotor blade icing is investigated. A numerical simulation method of three-dimensional rotor blade icing is presented. Body-fitted grids around the rotor blade are generated using overlapping grid technology and rotor flow field characteristics are obtained by solving N-S equations. According to Eulerian two-phase flow, the droplet trajectories are calculated and droplet impingement characteristics are obtained. The mass and energy conservation equations of ice accretion model are established and a new calculation method of runback water mass based on shear stress and centrifugal force is proposed to simulate water flow and ice shape. The calculation results are compared with available experimental results in order to verify the correctness of the numerical simulation method. The influence of centrifugal force on rotor icing is calculated. The results show that the flow direction and distribution of liquid water on rotor surfaces change under the action of centrifugal force, which lead to the increasing of icing at the stagnation point and the decreasing of icing on both frozen limitations.


2013 ◽  
Vol 734-737 ◽  
pp. 1488-1492
Author(s):  
Zhen Yu Liu ◽  
Li Hong Yao ◽  
Hu Zhen Wang ◽  
Cui Cui Ye

The fractures after artificial steering fracturing appear in shades of curved surface. Aiming at the problem of steering fracture, in the paper, numerical simulation method under the condition of three-dimensional two-phase flow is presented based on finite element method. In this method, of steering fracture was achieved by adopting surface elements fractures and tetrahedron elements to describe formation. By numerical simulation, the change rule of oil and water production performance of steering fractures can be calculated, and then the steering fracture parameters can be optimized before fracturing. A new method was supplied for the numerical simulation of artificial fractured well.


2014 ◽  
Vol 884-885 ◽  
pp. 104-107
Author(s):  
Zhi Jun Li ◽  
Ji Qiang Li ◽  
Wen De Yan

For the water-sweeping gas reservoir, especially when the water-body is active, water invasion can play positive roles in maintaining formation pressure and keeping the gas well production. But when the water-cone break through and towards the well bottom, suffers from the influencing of gas-water two phase flows, permeability of gas phase decrease sharply and will have a serious impact on the production performance of the gas well. Moreover, the time when the water-cone breakthrough will directly affect the final recovery of the gas wells, therefore, the numerical simulation method is used to conduct the research on the key influencing factors of water-invasion performance for the gas wells with bottom-water, which is the basis of the mechanical model for the typical gas wells with bottom-water. It indicate that as followings: (1) the key influencing factors of water-invasion performance for the gas wells with bottom-water are those, such as the open degree of the gas beds, well gas production and the amount of Kv/Kh value; and (2) the barrier will be in charge of great significance on the water-controlling for the bottom water gas wells, and its radius is the key factor to affect water-invasion performance for the bottom water gas wells where the barriers exist nearby.


Author(s):  
Yun Whan Na ◽  
J. N. Chung

Forced convective flow boiling in a single microchannel with different channel heights was studied through a numerical simulation method to investigate bubble dynamics, two-phase flow patterns, and boiling heat transfer. The momentum and energy equations were solved using a finite volume (FV) numerical method, while the liquid–vapor interface of a bubble is captured using the volume of fluid (VOF) technique. The effects of different constant wall heat fluxes and different channel heights on the boiling mechanisms were investigated. The effects of liquid velocity on the bubble departure diameter were also analyzed. The predicted bubble shapes and distribution profiles together with two-phase flow patterns are also provided.


Sign in / Sign up

Export Citation Format

Share Document