# Numerical analysis of air-water two-phase flow across a staggered tube bundle using an incompressible two-fluid model

## Abstract

The air-water two-phase flow across a staggered tube bundle at a pitch-top diameter ratio of 1.4 is analyzed by an incompressible two-fluid model using the upstream finite element method proposed in a prior study. The Reynolds number, based on the tube diameter and the volumetric velocity of the liquid phase at the tube gap, is 41,000, and the volumetric fraction of the gas phase upstream of the bundle {alpha}{sub g0} ranges from 0 to 0.15. The calculated flows exhibit unsteady and complicated behavior irrespective of {alpha}{sub g0}. The change in the drag coefficient of a tube in the bundle due to {alpha}{sub g0} agrees with the experimental result. The distribution of the volumetric fraction of the gas phase around the tube is also in good agreement with the measurement trend. These results indicate that the finite element method is usefully applicable to the two-phase-flow analysis in staggered tube bundles. It is also clarified that the unsteady flows are attributable to the occurrence and movement of vortices of both phases around the tubes.

- Authors:

- Publication Date:

- Research Org.:
- Nagoya Univ. (JP)

- OSTI Identifier:
- 20015676

- Resource Type:
- Journal Article

- Journal Name:
- Nuclear Science and Engineering

- Additional Journal Information:
- Journal Volume: 134; Journal Issue: 3; Other Information: PBD: Mar 2000; Journal ID: ISSN 0029-5639

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 42 ENGINEERING; NUMERICAL ANALYSIS; TWO-PHASE FLOW; FLOW MODELS; FINITE ELEMENT METHOD; UNSTEADY FLOW; VORTICES; HEAT EXCHANGERS; STEAM GENERATORS

### Citation Formats

```
Uchiyama, Tomomi.
```*Numerical analysis of air-water two-phase flow across a staggered tube bundle using an incompressible two-fluid model*. United States: N. p., 2000.
Web.

```
Uchiyama, Tomomi.
```*Numerical analysis of air-water two-phase flow across a staggered tube bundle using an incompressible two-fluid model*. United States.

```
Uchiyama, Tomomi. Wed .
"Numerical analysis of air-water two-phase flow across a staggered tube bundle using an incompressible two-fluid model". United States.
```

```
@article{osti_20015676,
```

title = {Numerical analysis of air-water two-phase flow across a staggered tube bundle using an incompressible two-fluid model},

author = {Uchiyama, Tomomi},

abstractNote = {The air-water two-phase flow across a staggered tube bundle at a pitch-top diameter ratio of 1.4 is analyzed by an incompressible two-fluid model using the upstream finite element method proposed in a prior study. The Reynolds number, based on the tube diameter and the volumetric velocity of the liquid phase at the tube gap, is 41,000, and the volumetric fraction of the gas phase upstream of the bundle {alpha}{sub g0} ranges from 0 to 0.15. The calculated flows exhibit unsteady and complicated behavior irrespective of {alpha}{sub g0}. The change in the drag coefficient of a tube in the bundle due to {alpha}{sub g0} agrees with the experimental result. The distribution of the volumetric fraction of the gas phase around the tube is also in good agreement with the measurement trend. These results indicate that the finite element method is usefully applicable to the two-phase-flow analysis in staggered tube bundles. It is also clarified that the unsteady flows are attributable to the occurrence and movement of vortices of both phases around the tubes.},

doi = {},

journal = {Nuclear Science and Engineering},

issn = {0029-5639},

number = 3,

volume = 134,

place = {United States},

year = {2000},

month = {3}

}