scholarly journals Numerical Analysis of the Diaphragm Valve Throttling Characteristics

Processes ◽  
2019 ◽  
Vol 7 (10) ◽  
pp. 671 ◽  
Author(s):  
Yingnan Liu ◽  
Liang Lu ◽  
Kangwu Zhu
Keyword(s):  
Flow Field ◽  
Pure Water ◽  
Water System ◽  
Flow Simulation ◽  
Side Wall ◽  
Internal Flow ◽  
Flow Path ◽  
Two Phase ◽  
Diaphragm Valve ◽  
Dimensional Simulation

The throttling characteristics of the diaphragm valve are numerically studied in this paper. Firstly, the diaphragm deformation performance is analyzed by a finite element method, while the upper boundary morphology of the internal flow field under different valve openings was obtained. Then the two-dimensional simulation of the weir diaphragm valve flow field is carried out in order to explore the optimal design of flow path profile. The study shows that the throttling characteristics can be improved by flatting the ridge side wall, widening the top of the ridge and gently flatting the internal protruding of the flow path. In addition, using the local grid encryption techniques based on velocity gradient adaptive and y+ adaptive can improve the accuracy of simulation results. Finally, a cavitation two-phase flow simulation is carried out. The results show that cavitation may occur below 50% opening of diaphragm valve in ultra-pure water system, which becomes more intense with the increase of inlet pressure and even leading to flow saturation on the micro-orifice state.

Research Analysis and Experiment Study on Flow Field of Hydrodynamic Coupling

2011 ◽  
Vol 418-420 ◽  
pp. 2006-2011
Author(s):  
Rui Zhang ◽  
Cheng Jian Sun ◽  
Yue Wang
Keyword(s):  
Flow Field ◽  
Cfd Simulation ◽  
Two Phase Flow ◽  
Three Dimensional ◽  
Internal Flow ◽  
Phase Flow ◽  
Complex Flow ◽  
Two Phase ◽  
Operation Conditions ◽  
Hydrodynamic Coupling

CFD simulation and PIV test technology provide effective solution for revealing the complex flow of hydrodynamic coupling’s internal flow field. Some articles reported that the combination of CFD simulation and PIV test can be used for analyzing the internal flow field of coupling, and such analysis focuses on one-phase flow. However, most internal flow field of coupling are gas-fluid two-phase flow under the real operation conditions. In order to reflect the gas-fluid two-phase flow of coupling objectively, CFD three-dimensional numerical simulation is conducted under two typical operation conditions. In addition, modern two-dimensional PIV technology is used to test the two-phase flow. This method of combining experiments and simulation presents the characteristics of the flow field when charging ratios are different.

CFD Simulation of Two-Phase Flow in a Downhole Venturi Meter

2011 ◽  
Vol 130-134 ◽  
pp. 3644-3647
Author(s):  
Ding Feng ◽  
Si Huang ◽  
Yu Hui Guan ◽  
Wei Guo Ma
Keyword(s):  
Optimal Design ◽  
Pressure Drop ◽  
Flow Field ◽  
Cfd Simulation ◽  
Two Phase Flow ◽  
Flow Simulation ◽  
Phase Flow ◽  
Feed Flow Rate ◽  
Two Phase ◽  
Oil Water

This work performs an oil-water two-phase flow simulation in a downhole Venturi meter to investigate the flow field and pressure characteristics with different flow and oil-water ratios. The relation between the pressure drop and the feed flow rate in the flowmeter is investigated for its optimal design.

scholarly journals Analysis of flow and phase interaction characteristics in a gas-liquid two-phase pump

2018 ◽  
Vol 73 ◽  
pp. 69 ◽  
Author(s):  
Wenwu Zhang ◽  
Zhiyi Yu ◽  
Yongjiang Li
Keyword(s):  
Discharge Coefficient ◽  
Flow Direction ◽  
Pure Water ◽  
Internal Flow ◽  
Turbulent Dispersion ◽  
Dispersion Force ◽  
Phase Interaction ◽  
Two Phase ◽  
Structured Grid ◽  
Interphase Force

To analyze the characteristics of internal flow and phase interaction in a gas-liquid two-phase pump, the influence of Inlet Gas Void Fraction (IGVF), discharge coefficient, and medium viscosity were investigated using medium combinations of air-water and air-crude. Simulations were performed using ANSYS_CFX at different IGVFs and various values of discharge coefficient. Structured grid for the full flow passage was generated using ICEM_CFD and TurboGrid. Under conditions of IGVF = 0% (pure water) and IGVF = 15%, the reliability of numerical method was proved by means of the comparison with the experimental data of external characteristic. The results for air-water combination showed a uniform gas distribution in the inlet pipe, and formation of a stratified structure in the outlet pipe. The gas in impeller gathered at the hub because of the rotation of the impeller, also, the interphase forces increased with the increased IGVF. For the two medium combinations, the drag force was the largest interphase force, followed by added mass and lift forces, and then the turbulent dispersion force was the least, which can be neglected. Because of the larger viscosity of crude than that of water, the variation trend of interphase forces in the impeller is relatively smooth along the flow direction when the medium combination was air-crude.

scholarly journals Interaction and influence of a flow field and particleboard particles in an airflow forming machine with a coupled Euler-DPM model

PLoS ONE ◽  
2021 ◽  
Vol 16 (6) ◽  
pp. e0253311
Author(s):  
Jian Zhang ◽  
Qing Chen ◽  
Minghong Shi ◽  
Hongping Zhou ◽  
Linyun Xu
Keyword(s):  
Flow Field ◽  
Raw Materials ◽  
Characteristic Point ◽  
Continuous Production ◽  
Internal Flow ◽  
Technical Difficulty ◽  
Calculation Model ◽  
Two Phase ◽  
Flow Field Characteristics ◽  
Uniform Diameter

Particleboards are widely used in the artificial board market, which can be constructed from a variety of raw materials and require small amounts of energy to be produced. In the particleboard production process, forming machines play an important role as the key equipment for achieving continuous production. In recent years, airflow forming machines have received increasing attention in particleboard production lines because of their strong separation ability and low price. However, the internal flow field is complex and difficult to control, which affects the surface quality and strength of the particleboard. The most pressing technical difficulty is controlling the flow field characteristics of the airflow paver. At present, the research on this subject is conducted primarily through repeated experiments, which entail long research periods and high processing costs. To reduce human and financial costs, in this study, Computational Fluid Dynamics (CFD) is employed to investigate the flow field and the gas-solid two-phase flow field coupled with particle movement of an airflow forming machine. The accuracy of the calculation model is verified by comparing characteristic point velocities obtained from experimental analysis and a simulation. The simulation results show that in practical production, the frequency of a negative pressure fan should be greater than 27 Hz. It is necessary to set the shoulder properly, and the slab smoothness can be improved by moving the shoulder back on the premise of meeting the strength requirements of the box. The distance between the shoulders of the box body should be less than 2570 mm, and particles with uniform diameter should be added to the paving box to reduce the turbulence effect, improve the quality of particle forming and provide actual particleboard production with a solid theoretical foundation.

scholarly journals Air Flow Simulation and Optimization for Negative Pressure Safflower Harvesting Device

2015 ◽  
Vol 9 (1) ◽  
pp. 773-779 ◽  
Author(s):  
Ge Yun ◽  
Zhang Lixin ◽  
Han Dandan ◽  
Zeng Haifeng ◽  
Zhang Xiang
Keyword(s):  
Flow Field ◽  
Air Flow ◽  
Flow Simulation ◽  
Internal Flow ◽  
Parabolic Type ◽  
Flow Speed ◽  
Low Velocity ◽  
Simulation And Optimization ◽  
Airflow Distribution ◽  
Cone Type

The safflower collection device is an important service part of safflower harvesting device, the number of the air outlets and external structure of air collecting hood are the main factors influencing the effect of the flower’s petals harvesting and collection. However, the design of pneumatic safflower harvest device is based on experience, resulting in long the design cycle, thus increasing the cost of design. Combined with the advantages of computational fluid dynamics software FLUENT, and the internal flow field of safflower closed style cover flowers as the research object, this paper designed gas collecting hood structures with different number of outlets through the analysis of the airflow distribution and motion law. The result of numerical simulation of gas-collecting hood with trapezoidal cone shows higher air flow speed with no low velocity zone, and the distribution of flow field of safflower collected cover with trapezoid cone type is better than that of parabolic type structure. Based on result of simulation, improved the design of the external shape of flowers cover and designed trapezoid cone type to improve the internal airflow state, thus could achieve the goal of improving efficiency of picking and collecting and reduce energy consumption.

scholarly journals Optimization the operation parameters of SDA desulfurization tower by flow coupling chemical reaction model

2020 ◽  
Vol 22 (1) ◽  
pp. 35-45
Author(s):  
Dan Mei ◽  
Junjie Shi ◽  
Yuzheng Zhu ◽  
Xuemei Xu ◽  
Futang Xing ◽  
...  
Keyword(s):  
Flow Field ◽  
Chemical Reaction ◽  
Flue Gas ◽  
Large Scale ◽  
High Efficiency ◽  
Internal Flow ◽  
Reaction Model ◽  
Field Calculation ◽  
Two Phase ◽  
Desulfurization Efficiency

AbstractSpray Drying Absorber (SDA) has been widely used for large-scale desulfurization. However, it also has some limitations. For example, the liquid absorbent easily causes scaling, which impedes the contact between the serous fluid and the flue gas and reduces the chemical reaction rate and desulfurization efficiency. This paper establishes the mathematical and physical model of gas and liquid two-phase flow and droplet evaporation and heat transfer in rotary spray desulfurization tower. To study the accumulation and distribution of chemical reaction precipitates in the desulfurization tower and analyze the removal efficiency of sulfur dioxide (SO2) in different atomization diameters, this paper establishes a simulation model concerning the coupling of desulfurization reaction and flow field calculation based on the absorption and reaction mechanism of SO2. Baffle in different widths are set to optimize the internal flow field and balance the distribution of flue gas. By setting baffles of different widths to optimize the flow field in the tower and changing the distribution of flue gas, this model reduces the scaling while ensuring the desulfurization efficiency. The results of the simulation experiment have verified that the droplet with a diameter of 50 μm is the optimal option, which can effectively remove the scaling and ensure that the desulfurizing tower runs in high efficiency and stability. When the width of baffles is 2250 mm, the efficiency of desulfurization exceeds 95%, and the amount of scaling on the desulfurization tower main wall is controlled at the minimum level, which is the optimal option for production.

Simulation and experimental study on cavitation and noise of hydraulic cone valve

2019 ◽  
Vol 71 (2) ◽  
pp. 318-323
Author(s):  
Xiaojing Wang ◽  
Hao Liu ◽  
Guojia Man
Keyword(s):  
Flow Field ◽  
Noise Level ◽  
Cone Angle ◽  
Internal Flow ◽  
Radial Force ◽  
Theoretical Research ◽  
Two Phase ◽  
Content Type ◽  
Radial Deviation ◽  
Icem Cfd

PurposeAiming at the cavitations and noise problem of hydraulic cone valve and based on the radial force analysis of the valve core, the radial deviation of the spool is considered to obtain the changing rules of cavitations and noise.Design/methodology/approachThe solid model of the internal flow field of cone valve is established. The mesh models are divided using ICEM-CFD software. The numerical simulation of the liquid-gas two-phase flow is performed on the cavitation and noise of the flow field inside the cone valve based on FLUENT software. The visible experimental platform for cavitation and noise of hydraulic cone valve is built. According to the contrast of the experimental results, the correctness of the simulation results is verified.FindingsThe results show that the radial deviation causes the position of the cavitation accumulates in the valve cavity on the side of the upper cone. In addition, the strength of the cavitation changes slowly with the half cone angle of 45°, and the noise level is the smallest. Furthermore, appropriately increasing the opening degree within a reasonable range can effectively suppress cavitation and reduce the noise level.Originality/valueThe cavitation can be suppressed and the noise level can be reduced by means of changing the three factors, which lays the foundation for the design and theoretical research of the cone valve.

Numerical Study on Flow Characteristics in a Stirring Vessel

2011 ◽  
Vol 130-134 ◽  
pp. 3050-3053
Author(s):  
Ru Quan Liang ◽  
Jun Hong Ji ◽  
Fu Sheng Yan ◽  
Ji Cheng He
Keyword(s):  
Flow Field ◽  
Numerical Study ◽  
Fluid Model ◽  
Rotational Velocity ◽  
Flow Characteristics ◽  
Internal Flow ◽  
Experimental Result ◽  
Flow Rule ◽  
Two Phase ◽  
Impeller Type

In order to improve the desulphurization efficiency of KR mixing method in the process of molten iron refining, the method of CFD was used to analyze the flow field in a stirring vessel. The Fluent software was adopted to simulate and analyze the internal flow rule in a 3D stirring vessel with the method of multiple reference frame approach, and the corresponding models of Euler two-phase flow fluid model and standard k-ε turbulence model were used. By comparing with the experimental result, the influence of important parameters of agitator on internal flow field in the stirring vessel, such as rotational velocity, immersion depth and impeller type was discussed, and the flow structure was analyzed as well.

The Application of Machine Learning Algorithm in Relative Permeability Upscaling for Oil-Water System

2021 ◽  
Author(s):  
Yanji Wang ◽  
Hangyu Li ◽  
Ji Tian ◽  
Ling Fan ◽  
Jianchun Xu
Keyword(s):  
Machine Learning ◽  
Relative Permeability ◽  
Learning Algorithm ◽  
Water System ◽  
Flow Simulation ◽  
Machine Learning Algorithm ◽  
Fine Scale ◽  
Two Phase ◽  
Permeability Upscaling ◽  
Similar Accuracy

Abstract Traditional two-phase relative permeability upscaling requires the fine-scale two-phase flow simulation over the target regions/blocks. It can be very computationally expensive especially for cases with multiple (hundreds of) geological realizations (as commonly used in subsurface uncertainty quantification or optimization). In this paper, we develop a machine learning assisted relative permeability upscaling procedure, in which the full numerical upscaling is performed for only a portion of the coarse blocks, while the upscaled functions for the rest of the coarse blocks are calculated by the machine learning algorithm. The upscaling procedure was tested for generic (left to right) flow problems using 2D models for scenarios involving multiple realizations. Numerical results have shown that the coarse-scale simulation results using the newly developed machine learning assisted upscaling procedure are of similar accuracy to the coarse results using full numerical upscaling. Because the fine-scale numerical simulation is only performed for a small fraction of the model, significant speedup is achieved.

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