PHASE DISTRIBUTION AND PRESSURE DROP OF AIR-WATER FLOWS IN A HORIZONTAL IMPACTING TEE JUNCTION

Abstract Vertical swirling gas-liquid flow is a kind of complex two-phase flow containing a nonzero tangential velocity component in engineering applications. The accurate flow regime characterization, phase distribution information and pressure drop data about vertical swirling flow are the basis for the optimization of steam generator (SG), which can greatly reduce the cost and improve the safety of nuclear plants. To get these key parameters of swirling vertical flow, we have made a comprehensive visualization experiment in a vertical pipe with 30mm diameter and 5m length by high-speed camera. The experimental pipe is separated into swirling part and non-swirling part. We have set three observation section with different vertical heights in the swirling part. Changing the flow rate of water and gas, different swirling flow pattern photos can be captured by high-speed camera. Based on the photos of different positions and image-processing MATLAB code, we can get three flow regime maps and figure out the decaying law of swirling gas-liquid flow. The pressure drop can be recorded by rotameter at each position. The decaying law of pressrure drop can be concluded from it. These data can be a guide for designing gas-liquid separator in SG to improve the efficiency of nuclear plant.

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Pressure drop below the load zone in a Raschig-ring packed column with countercurrent air—water flows

The Chemical Engineering Journal ◽

10.1016/0300-9467(74)85041-0 ◽

1974 ◽

Vol 7 (3) ◽

pp. 257-260 ◽

Cited By ~ 5

Author(s):

J. Andrieu

Keyword(s):

Pressure Drop ◽

Packed Column ◽

Raschig Ring ◽

Water Flows

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Effect of inclination on frictional pressure drop of supercritical water flows in internally ribbed tubes: An experimental study

The Journal of Supercritical Fluids ◽

10.1016/j.supflu.2017.02.003 ◽

2017 ◽

Vol 125 ◽

pp. 56-65 ◽

Cited By ~ 4

Author(s):

Alireza Taklifi ◽

Abbas Aliabadi ◽

Pedram Hanafizadeh ◽

Mohammad Ali Akhavan-Behabadi

Keyword(s):

Experimental Study ◽

Pressure Drop ◽

Supercritical Water ◽

Frictional Pressure Drop ◽

Water Flows

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Drag Reduction with Biopolymer-Synthetic Polymer Mixtures in Oil-Water Flows: Effect of Synergy

Engineering Journal ◽

10.4186/ej.2020.24.6.1 ◽

2020 ◽

Vol 24 (6) ◽

pp. 1-10

Author(s):

Lawrence Chukwuka Edomwonyi-Otu ◽

Muhammed Muhammed Gimba ◽

Nurudeen Yusuf

Keyword(s):

Reynolds Number ◽

Pressure Drop ◽

Pressure Gradient ◽

Drag Reduction ◽

Water Flow ◽

Transport Systems ◽

Test Fluid ◽

Polymer Mixture ◽

Water Flows ◽

Oil Water

The search for lower cost materials that reduce pressure drop in fluid transport systems in oil and gas industries to conserve pumping energy is of paramount importance. Polymers are known to reduce pressure drop in pipeline oil-water flows in a process referred to as drag reduction (DR). The effect of partially hydrolysed polyacrylamide, polyethylene oxide, Aloe Vera mucilage and their mixtures as drag reducing polymers (DRPs) on pressure gradient (pressure drop; Δp) in pipeline oil-water flows were studied. The experiment was carried out in flow rig with 0.02-m diameter straight unplasticised polyvinylchloride (uPVC) pipe, two centrifugal pumps, control valves and two storage tanks. Tap water (ρ = 997 kg/m3 and µ = 0.89 cP) and diesel (ρ = 832 kg/m3 and µ = 1.66 cP) were used as the test fluid at ambient condition. The polymer mixture total concentration (MTC) of 30 and 400 ppm at different mixing proportion, mixture Reynolds number (Remix) and oil input volume were investigated. The results show increase in pressure gradient with increase in oil input volume in both single-phase water flow and oil-water flow before adding drag reducing polymers (DRPs). However, Δp decreased after adding DRPs with increase in Reynolds number (Re) or Remix and decrease in the oil-phase Re, and vice versa. The results further showed higher reduction in pressure drop by the polymer mixture than in each of the polymer used at the same conditions. The rigidness of the biopolymer was improved by adding synthetic polymers which resulted to increase in DR efficiency.

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Experimental Investigation on Heat Transfer and Pressure Drop of Supercritical Water Flows in 2×2 Bundle With Wire Wraps

Volume 6: Thermal-Hydraulics ◽

10.1115/icone25-66898 ◽

2017 ◽

Author(s):

Li Hong-bo ◽

Hu Zhen-xiao ◽

Lu Dong-hua ◽

Gu Han-yang

Keyword(s):

Heat Transfer ◽

Experimental Investigation ◽

Pressure Drop ◽

Supercritical Water ◽

Critical Conditions ◽

Bulk Temperature ◽

Experimental Conditions ◽

Water Flows ◽

Dc Power ◽

Test Loop

An experimental investigation on heat transfer of supercritical water and transient heat transfer during pressure drop from supercritical to sub-critical conditions in a 2×2 bundle with two channels has been carried out on the supercritical water multipurpose test loop II (SWAMUP-II). The bundle consists of four heated rods with an O.D. of 10 mm and a pitch-to-diameter ratio of 1.18. The 2×2 bundle with wire wrap is installed into a square assembly box with rounded corners by which the test section is separated into two channels. Water flows downward in the first channel between the pressure tube and the assembly box, and then turns upward in the second channel inside the assembly box to cool the four heated rods, which are directly heated by DC power. The experimental conditions are as follows: pressure ranging from 16 to 26 MPa, mass flux from 400 to 1450 kg/m2s, heat flux from 250 to 1000 kW/m2, bulk temperature from 280 to 500 °C, and pressure drop rate of 1 and 2 MPa/min. The experimental data are obtained and heat transfer characteristics discussed.

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