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

Experimental study on resistance of air-water two-phase flow in a vertical 3 × 3 rod bundle was carried out under normal temperature and pressure. The rod diameter and pitch were 8 mm and 11 mm, respectively. The ranges of gas and liquid superficial velocity were 0.013∼3.763 m/s and 0.076∼1.792 m/s, respectively. The result indicated that the existing correlations for calculating frictional coefficient in the rod bundle and local resistance coefficient could not give favorable predictions on the single-phase experimental data. For the case of two-phase flow, eight correlations for calculating two-phase equivalent viscosity poorly predicted the frictional pressure drop, with the mean absolute errors around 60%. Meanwhile, the eight classical two-phase viscosity formulae were evaluated against the local pressure drop at spacer grid. It is shown that Dukler model predicted the experimental data well in the range of Rel<9000 while McAdams correlation was the best for Rel⩾9000. For all the experimental data, Dukler model provided the best prediction with MRE of 29.03%. Furthermore, approaches to calculate two-phase frictional pressure drop and local resistance were proposed by considering mass quality, two-phase Reynolds number and densities in homogenous flow model, resulting in a good agreement with the experimental data.

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An experimental study of flow boiling frictional pressure drop of R134a in a horizontal 1.002 mm tube under hypergravity

International Journal of Heat and Mass Transfer ◽

10.1016/j.ijheatmasstransfer.2017.10.120 ◽

2018 ◽

Vol 118 ◽

pp. 247-256 ◽

Cited By ~ 1

Author(s):

Guohua Li ◽

Xiande Fang ◽

Yuliang Yuan ◽

Yanyu Chen ◽

Li Wang ◽

...

Keyword(s):

Experimental Study ◽

Pressure Drop ◽

Flow Boiling ◽

Frictional Pressure Drop

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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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