Numerical Analysis of Flow Field Characteristics in Three-Z-Shaped Ultrasonic Flowmeter

2012 ◽  
Vol 226-228 ◽  
pp. 1829-1834 ◽  
Author(s):  
Jing Yuan Tang ◽  
Jian Ming Chen ◽  
Hong Bin Ma ◽  
Guang Yu Tang

The flow field characteristics in U-typed bend has been extensively studied for transit time ultrasonic flowmeters designing, but for the flowmeter with three-Z-shaped round pipe there is still lack of corresponding research. This paper presents a computational fluid dynamics (CFD) approach for modeling of the three-Z-shaped ultrasonic flowmeter and studying of internal fluid field characteristics based on Reynolds stress model (RSM). The fluid velocity profile in the three ultrasound path is obtained using CFD and secondary flow in cross section also is analyzed. The simulation results show that the internal flow fields in the flowmeter are not fully developed turbulence with asymmetric axial velocity distribution and dramatic changes along the flow direction, and there are obvious secondary cross flows on theirs cross-sections. The CFD simulations provide useful insights into the flow field associated with ultrasonic flowmeters design.

Water ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 1142
Author(s):  
Dagang Zhao ◽  
Chunyu Guo ◽  
Tiecheng Wu ◽  
Wei Wang ◽  
Xunbin Yin

In this study, particle image velocimetry was used to measure the fine flow-field characteristics of an L-type podded propulsor in various working conditions. The flow-field details at different cross-sections between the propeller and the inclined bracket were compared and analyzed, allowing for more intuitive comparison of the flow-field characteristics of L-type podded propulsors. The interference mechanisms among the propeller, pod, and bracket of the L-type podded propulsors at different advance coefficients, deflection angles, and deflection directions were investigated in depth. The results of this study can serve as reference material and provide technical support for the design and practical shipbuilding application of L-type podded propulsors. Therefore, the results have theoretical significance and practical engineering value.


2015 ◽  
Vol 2015 ◽  
pp. 1-7
Author(s):  
Yan Xu ◽  
Zunce Wang ◽  
Lin Ke ◽  
Sen Li ◽  
Jinglong Zhang

Reynolds Stress Model and Large Eddy Simulation are used to respectively perform numerical simulation for the flow field of a hydrocyclone. The three-dimensional hexahedral computational grids were generated. Turbulence intensity, vorticity, and the velocity distribution of different cross sections were gained. The velocity simulation results were compared with the LDV test results, and the results indicated that Large Eddy Simulation was more close to LDV experimental data. Large Eddy Simulation was a relatively appropriate method for simulation of flow field within a hydrocyclone.


Author(s):  
Yigang Luan ◽  
Lianfeng Yang ◽  
Tao Sun

Axial flow cyclone separator with guide blade has been widely used, due to its low resistance, huge gas processing and small volume. Although its structure is simple, three-dimension strong rotating turbulent flow forms which involves many complex interactions such as dual-phase separation, adsorption and electrostatic interference. This paper is focused on studying the resistance performance of the axial flow cyclone separator. Numerical simulation methods are carried out to acquire the internal flow field characteristics under different operating pressure and temperature conditions. The result shows that the pressure drop decreases under the same operating pressure, as the operating temperature increases. When the operating temperature is the same, the higher operating pressure enhances the value of the pressure drop. Velocity distribution, pressure contours and turbulent viscosity contours have been presented, to analyze the characteristics of the internal airflow, so as to help optimize the design. Experiments are intended to verify the results of numerical simulation and explore the internal flow field of the cyclone separator further. The cyclone separator has 8 rotary blades which are split into 8 parts, namely one blade is 45° in the tangential direction. 0° and 22.5° are chosen in the experiment. The dimensionless pressure distribution is shown. A comparison of the CFD results and the experimental results is made to prove that the numerical simulation methods are correct and accurate. The curve of the numerical simulation results is very close to that of the experimental results with the similar trend. It is concluded that the methods can predict the internal flow field characteristics of the axial flow cyclone separator.


2013 ◽  
Vol 373-375 ◽  
pp. 409-412
Author(s):  
Zhi Guo Zhao ◽  
Wen Ming Yu

Aiming at the low efficiency problem of the traditional gas-oil separator, this paper put forward a centrifugal gas-oil separator. In order to identify out the interior fluid field character of centrifugal gas-oil separator, RANS equation, RNG k-ε model and discrete phase model was applied to simulate the interior fluid field character and separation efficiency of centrifugal gas-oil separator. The simulation results showed that the flow field in the disc clearance was mainly laminar flow, and the flow field at the import and export of the disc was turbulence. Meanwhile, the velocity and pressure of the interior fluid field were equably distributed, the velocity and pressure in the disc clearance fluctuate in a tight range along vertical direction, and decrease along horizontal direction, and the particles in the disc clearance were distributed uniformly. The separation efficiency was 96.6% and the results met the design requirements.


2013 ◽  
Vol 805-806 ◽  
pp. 1874-1877
Author(s):  
Jie Nan Dong ◽  
Xu Su ◽  
Tong Chen ◽  
Miao Wang ◽  
Xiao Xu Li

In this paper,using numerical simulation tools PHOENICS for numerical simulation study is made on furnace gas burning in the hearth, and analyses furnace oil furnace temperature distribution in the flow field characteristics the internal flow field of oil field heating furnace hearth temperature distribution characteristics. On this basis, this paper establisheda mathematical model which can truly describe the chamber internal physical and chemical changes, selected the appropriate numerical simulation methods, plotted the actual temperature profile case, which can reflect the qualitative and quantitative actual situation of work.Finally suggestions are given, which provides the theoretical foundation for the next step and the actual research.


Author(s):  
Li Guoqi ◽  
Lin Peifeng ◽  
Cui Baoling ◽  
Jin Yingzi ◽  
Hu Yongjun ◽  
...  

With the advent of bladeless fan, technological revolutions begin to hit the industrial design world of fan. However, there is none of the developed methods on bladeless fan. To explore the excellent blowing performance of bladeless fan, numerical simulation on flow field of bladeless fan was carried out in this paper. Based on the simplified model of bladeless fan, the whole process that the airflow passes through the turbine from the inlet to the outlet slit and exit far field at last, were simulated. By comparing the flux of inlet and the flux of far outlet, the causes of flux increasing are analyzed. After analyzing static characteristics of the flow field, it shows that pressure difference is very obvious. The results obtained from velocity distribution and the characteristics of the pathlines near diffuser section and turbine, were described and analyzed. The results show that the internal flow field characteristics of bladeless fans, which we concern. The external flow field characteristics of bladeless fan was studied in the same way. And it is found that the velocity magnitude of the outlet slit and Coanda surface is much larger than other area and different positions play different roles. A general analysis on inside computational domain and outside computational domain, denotes the details about fluid motion. The research could offer reference to improvement of bladeless fan.


2013 ◽  
Vol 397-400 ◽  
pp. 257-260 ◽  
Author(s):  
Yan Tao An ◽  
Ru Jian Ma ◽  
Yong Wang

Establish valve stem leakage flow channel model, apply the CFD numerical simulation the internal flow field and noise. Research shows that it is no effect on the valve inlet and outlet flow field when the valve stem leakage. It is no effect on the valve body flow field and the greatest influence the balance cavity flow field. Changing the flow direction of the balance cavity and produce left vortex, it break left vortex of right part. New tremendous noise sources appear the balance cavity and improve the noise of surrounding areas.


PLoS ONE ◽  
2021 ◽  
Vol 16 (6) ◽  
pp. e0253311
Author(s):  
Jian Zhang ◽  
Qing Chen ◽  
Minghong Shi ◽  
Hongping Zhou ◽  
Linyun Xu

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.


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