Countercurrent Gas-Liquid Flow in a PWR Hot Leg under Reflux Cooling (II) Numerical Simulation of 1/15-Scale Air-Water Tests

Minami, Noritoshi; Murase, Michio; Tomiyama, Akio

doi:10.1080/18811248.2010.9711939

Cited by 22 publications

(23 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Figure 9 shows a comparison of the predicted CCFL characteristics with the measured data. 11) As previously reported, 12) model without the expansion) were in excellent agreement with the measured CCFL characteristics including the hysteresis. In the simulations of the expanding pipe, the CCFL did not occur at the upper end of the inclined pipe, and the CCFL in the horizontal pipe occurred at a higher J G than that in the case of no expansion.…”

Section: Computational Gridsupporting

confidence: 72%

“…(3)- (8) was confirmed for the 1/15 th scale tests. 12) In the validation, the hysteresis in the flow pattern was successfully simulated and the predicted CCFL characteristics agreed well with the measured data. In the tests and simulations, however, the expansion of the inclined pipe in a real PWR hot leg was not simulated.…”

Section: Gas-liquid Interfacial Friction Coefficientssupporting

confidence: 54%

See 1 more Smart Citation

Numerical Simulation of Countercurrent Gas-Liquid Flow in a PWR Hot Leg under Reflux Cooling

Kinoshita¹,

Murase²,

Utanohara³

et al. 2010

Journal of Nuclear Science and Technology

Self Cite

View full text Add to dashboard Cite

In reflux cooling, the steam generated in the reactor core and the water condensed in a steam generator form a countercurrent flow in a hot leg. In order to investigate flow patterns in the hot leg under countercurrent flow conditions, countercurrent air-water tests were previously conducted using a 1/15 th scale model of a PWR hot leg. Numerical simulation results for the tests using a three-dimensional twofluid model in FLUENT6.3.26, implemented with an appropriate set of correlations for the gas-liquid interfacial friction, were in good agreement with the measured data. In the present study, further numerical simulations were carried out for a full-scale hot leg under PWR plant conditions to investigate the effects of pipe diameter and fluid properties. The predicted countercurrent flow limitation characteristics were well correlated with the Wallis parameters and agreed well with the measured data from the 1/15 th scale air-water tests as well as the full-scale steam-water UPTF tests. The results indicate that the set of correlations for the gas-liquid interfacial friction can be utilized to simulate countercurrent flows in the full-scale PWR hot leg.

show abstract

Section: Computational Gridsupporting

confidence: 72%

Section: Gas-liquid Interfacial Friction Coefficientssupporting

confidence: 54%

Numerical Simulation of Countercurrent Gas-Liquid Flow in a PWR Hot Leg under Reflux Cooling

Kinoshita¹,

Murase²,

Utanohara³

et al. 2010

Journal of Nuclear Science and Technology

Self Cite

View full text Add to dashboard Cite

show abstract

“…(4)- (9) was confirmed for the 1/15 th scale air-water experiments. (12) In the validation, the hysteresis in the flow pattern was successfully simulated and the predicted CCFL characteristics agreed well with the measured data. The problem which must be dealt with is whether the interfacial drag coefficients, Eqs.…”

Section: Interfacial Drag Coefficientssupporting

confidence: 54%

“…Previously, three-dimensional two-fluid model simulations were used to reproduce the observed flow patterns and CCFL characteristics for air/water experiments with the 1/15 th scale model. (12) However, the applicability of the method, especially of the interfacial drag coefficients to CCFL, requires further validation for a wide range of fluid properties. Numerical simulations for the above experiments were therefore conducted.…”

Section: Numerical Simulationsmentioning

confidence: 99%

Effects of Liquid Properties on CCFL in a Scaled-Down Model of a PWR Hot Leg

Kinoshita

Nriai

Tomiyama

et al. 2011

JPES

Self Cite

View full text Add to dashboard Cite

This paper describes the effects of liquid properties on countercurrent flow limitation (CCFL) in a PWR hot leg. CCFL experiments were conducted in a 1/15 th scaled-down model of the hot leg using air/water and air/glycerol-water solutions as working fluids. The experimental results revealed that an increase in the liquid viscosity did not change the zero liquid penetration point but did increase the slope of the CCFL curves on the Wallis diagram, which indicated that the increase in liquid viscosity from that of water did not affect the interfacial drag force but did influence the wall friction force. Numerical simulations of the experiments were carried out using a two-fluid model implemented in the CFD software FLUENT 6.3.26, and it was confirmed that the two-fluid model simulations properly evaluated the effects of liquid viscosity on the CCFL characteristics in the hot leg. Numerical simulations were also carried out to compare a low viscosity liquid to water. The predicted CCFL characteristics for low viscosity liquid showed no significant difference from those for water, which indicated that the decrease in liquid viscosity from that of water affected neither the interfacial force nor the wall friction force.

show abstract

“…One was a 1/5th scale rectangular duct (Minami et al, 2008a), and the other was a 1/15th scale circular pipe (Minami et al, 2010a). Then we carried out numerical simulations of these small scale experiments to investigate flow pattern and CCFL characteristics (Minami et al, 2008b and2010b). We used a three-dimensional two-fluid model to evaluate the capability of predicting countercurrent flow in the hot leg.…”

Section: Introductionmentioning

confidence: 99%