Study on Distribution Performance of a New Oil-Air Distributor in Oil-Air Lubrication System

The fluid domain model of a new oil-air distributor in oil-air lubrication system is built and the phase distribution of oil and air two-phase flow on distribution interface is simulated based on the CFD model in Fluent, the mass flow rate of oil and air are collected from three different cross sections when the structures of oil-air guidance slot are designed as a plane, sphere and cone shape respectively, then the influence of oil-air guidance slot structure on the performance of distributor is analyzed in the oil-air lubrication system in this paper. The results show that the spherical surface and conical surface of oil-air guidance slot can improve the uniformity and stability of the oil and air two-phase flow distribution, promote the flow pattern to form a continuous annular oil film. Among these three structures of oil-air guidance slot, we also find that the distribution performance of conical surface is the best.

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Two-Phase Flow Distribution in a Compact Heat Exchanger Header

1st International Conference on Microchannels and Minichannels ◽

10.1115/icmm2003-1063 ◽

2003 ◽

Cited By ~ 2

Author(s):

Jong-Soo Kim ◽

Yong-Bin Im ◽

Jae-Hong Kim ◽

Ki-Taek Lee

Keyword(s):

Heat Exchanger ◽

Two Phase Flow ◽

Phase Distribution ◽

Flow Distribution ◽

Compact Heat Exchanger ◽

Phase Flow ◽

Two Phase ◽

Insertion Depth ◽

Different Types ◽

Uniform Liquid

In this paper an experimental study was investigated for two-phase distribution in compact heat exchanger header. A test section was consisted of the horizontal header (circular tube: φ 5 mm × 80 mm) and 10 upward circular channels (φ 1.5 mm × 850 mm) using acrylic tube. Three different types of tube insertion depth were tested for the mass flux and inlet quality ranges of 50–200 kg/m2s and 0.1–0.3, respectively. Air and water were used as the test fluids. The distribution of vapor and liquid is obtained by measurement of the total mass flow rate and the calculation of the quality. Two-phase flow pattern was observed, and pressure drop of each channel was measured. By adjusting the insertion depth of each channel a uniform liquid flow distribution through the each channel was able to solve the mal-distribution problem.

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Complexity of phase distribution in two-phase flow using composite multiscale entropy

The European Physical Journal Plus ◽

10.1140/epjp/s13360-020-00686-0 ◽

2020 ◽

Vol 135 (8) ◽

Author(s):

Gabriela Rafałko ◽

Romuald Mosdorf ◽

Grzegorz Litak ◽

Grzegorz Górski

Keyword(s):

Gas Phase ◽

Two Phase Flow ◽

Phase Distribution ◽

Digital Camera ◽

Flow Distribution ◽

Multiscale Entropy ◽

Phase Flow ◽

Two Phase ◽

Flow Rates ◽

Water Glycerol

AbstractMultiphase flow in a minichannel is a complex phenomenon which shows various patterns dynamics including slugs and bubbles depending on gas/fluid component flow rates. In this paper, air and water–glycerol mixed fluid flow has been studied. In the experiment, the volume flow rates of air and water–glycerol were changing. We studied transition of bubbles to slugs two-phase flow patterns by using multiscale entropy approach to digital camera signals and identified various patterns. The results clearly indicate that the multiscale entropy is an important complexity measure dependent on the flow distribution of the gas phase in a water–glycerol content.

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Study on Gas-Liquid Two-Phase Flow Distribution Inside a Flute Header

ASME 2020 Power Conference ◽

10.1115/power2020-16710 ◽

2020 ◽

Author(s):

Liping Pang ◽

Shangmin Li ◽

Hu Yuan ◽

Liqiang Duan

Keyword(s):

Liquid Phase ◽

Gas Phase ◽

Liquid Flow ◽

Two Phase Flow ◽

Phase Distribution ◽

Flow Distribution ◽

Phase Flow ◽

Two Phase ◽

Parallel Channels ◽

Gas Liquid Flow

Abstract When the supercritical boiler is working at low load during flexible operation, the uneven distribution of the gas-liquid flow at the intermediate header may affect the safety of the water-cooled wall at the vertical parallel panels. In order to improve the uniformity of gas-liquid flow distribution in the water-cooled wall of intermediate header and study the internal flow mechanism, a flute inside the header is applied with parallel vertical parallel channels and experiments under different operating conditions are conducted to verify the effectiveness of this geometrical structure. The flow pattern in the experiment belongs to stratified and wavy flow. Computational fluid dynamic (CFD) simulation is conducted in order to investigate two-phase flow distribution behavior inside a flute header. It was found that the radial gas phase distribution in the flute tube shows a symmetrical relationship, and there are two vortexes in opposite directions. With the increasing distance from the inlet, the uniformity of the gas phase distribution becomes even. The gravity is greater than the drag force, which has effect on the two-phase flow distribution. The gas phase velocity has been improved inside flute section and liquid phase flow has more even flow distribution along annular section. It makes liquid phase sent to far end of flute header. That benefits two-phase flow distribution along 10 parallel channels equally.

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