Simultaneous Shape and Permittivity Reconstruction in ECT With Sparse Representation: Two-Phase Distribution Imaging

2021 ◽  
Vol 70 ◽  
pp. 1-14
Author(s):  
Wenbin Tian ◽  
Peng Suo ◽  
Dong Liu ◽  
Shijie Sun ◽  
Jiangtao Sun ◽  
...  
Keyword(s):  
Sparse Representation ◽  
Phase Distribution ◽  
Two Phase

scholarly journals Phase Distribution in the Tip Clearance of a Multiphase Pump at Multiple Operating Points and Its Effect on the Pressure Fluctuation Intensity

Processes ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 556
Author(s):  
Guangtai Shi ◽  
Zongku Liu ◽  
Xiaobing Liu ◽  
Yexiang Xiao ◽  
Xuelin Tang
Keyword(s):  
Phase Velocity ◽  
Pressure Fluctuation ◽  
Phase Distribution ◽  
Tip Clearance ◽  
Tip Leakage Flow ◽  
Two Phase ◽  
Multiphase Pump ◽  
Fluctuation Intensity ◽  
Operating Points ◽  
Multiple Operating Points

Tip clearance has a great effect on the flow and pressure fluctuation characteristics in a multiphase pump, especially at multiple operating points. The phase distribution and pressure fluctuation in tip clearance in a multiphase pump are revealed using the CFD (computational fluid dynamics) technology and high-speed photography methods. In this paper, the phase distribution, the gas-liquid two-phase velocity slip, and the pressure fluctuation intensity are comprehensively analyzed. Results show with the increase of the tip clearance, the multiphase pump pressurization performance is obviously deteriorated. In the meantime, the gas accumulation mainly occurs at the hub, the blade suction side (SS), and the tip clearance, and the maximum gas-liquid two-phase velocity difference is near the impeller streamwise of 0.4. In addition, the tip clearance improves the gas-liquid two-phase distribution in the pump, that is, the larger the tip clearance is, the more uniform the gas-liquid distribution becomes. Furthermore, the gas leads to the maximum pressure fluctuation intensity in the tip clearance which is closer to the tip leakage flow (TLF) outlet, and has a greater effect on the degree of flow separation in the tip clearance.

CFD simulation of air effect on flow field characteristics of hydro-viscous clutch with constant speed difference

2018 ◽  
Vol 19 (2) ◽  
pp. 208
Author(s):  
Xudong Zheng ◽  
Fangwei Xie ◽  
Diancheng Wu ◽  
Xinjian Guo ◽  
Bing Zhang ◽  
...  
Keyword(s):  
Flow Field ◽  
Cfd Simulation ◽  
Power Transmission ◽  
Volume Fraction ◽  
Phase Distribution ◽  
Constant Speed ◽  
Distribution Law ◽  
Two Phase ◽  
Oil Film ◽  
Speed Difference

The purpose of this paper is to study the air effects on transmission characteristics of hydro-viscous clutch and reveal the distribution law of the flow field of the oil film. The computational-fluid-dynamics (CFD) simulation model of oil film with radial oil grooves between friction pairs is taken as the study object. Considering the air effects, the pressure field, two-phase distribution, transmission torque and temperature field of the oil film are analyzed comparatively by using the CFD technology. The results show that the presence of air changes the pressure and temperature distributions of the oil film. With increase of the absolute rotational speed, the air volume fraction increases and the radius value of the air-liquid boundary decreases under condition of constant speed difference, which makes the coverage rate of the oil film on the surface of the friction disks reduce and the transmission torque of the oil film decrease. These simulation results are attributed to the study of hydro-viscous-drive and its applications. This paper also can provide a theoretical basis for the mechanism of power transmission through oil film in the presence of air effects.

scholarly journals Effects of Two Phase Turbulent Structure Interactions on Phase Distribution in Bubbly Pipe Flows.

1999 ◽  
Vol 42 (3) ◽  
pp. 419-428 ◽  
Author(s):  
T.C. KUO ◽  
A.S. YANG ◽  
C. PAN ◽  
C.C. CHIENG
Keyword(s):  
Phase Distribution ◽  
Turbulent Structure ◽  
Two Phase ◽  
Pipe Flows

Effect of Variable Heating Load on the Refrigerant Distribution of a Dual Cold-Plate System

2009 ◽  
Vol 131 (2) ◽  
Author(s):  
Cheng-Wei Tien ◽  
Kun-Huang Yu ◽  
Wen-Junn Sheu ◽  
Chi-Chuan Wang
Keyword(s):  
Phase Distribution ◽  
Cold Plate ◽  
Two Phase ◽  
Nominal Capacity ◽  
Mass Flowrate ◽  
Heating Load ◽  
Cold Plates ◽  
The Difference ◽  
R 134A ◽  
Plate System

This study examines the refrigerant distribution of a dual cold-plate system subject to the influence of heating load, using a R-134a based vapor compression system with a nominal capacity ranging from 50 W to 250 W. The cold plate is of identical configuration. Initially, test is performed under an equal heating load for each cold plate (70 W), which then gives rise to a uniform distribution and equal outlet superheat condition. For an unequal heating load, it is found that the distribution of mass flowrate subject to the influence of heating load is strongly related to the outlet states of the two cold plates. For the condition where one of the cold plates is in superheated state while the other is in saturated state, the mass flowrate for the fixed heating load is lower than that of smaller heating load, and the difference increases when the heating load gets smaller due to the influence of accelerational pressure drop. A maximum of 17% difference is seen at a loading ratio of 0.571 (40 W/70 W). For the condition where both outlet states of the cold plate are at superheated states, the mass flowrate for the fixed heating load is marginally higher than that of the smaller heating load, and the difference is insensitive to the increase in heating load. For this situation, the effect of accelerational pressure is negligible, and it is mainly attributed to two-phase/single-phase distribution pertaining to the effect of heating load.

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