18.08.2015   NUCLEAR POWER PLANTS

Representative published tests on two-phase flow across tube arrays

Table 6, an extension of period beyond 1993 (Pettigrew et al., 1973) presents a summary of salient features of the experimental tests performed on the three possible tube arrangements (triangular, normal square, and rotated square).

Researchers

Fluid

Tube Array

Void Fraction

Tube

Length

(mm)

Natural

Frequency

(Hz)

Damping Ratio (%)

(Inada et al., 2000)

Air-Water

Square

0-70%

198

15

-2.5- +1.6% Eq.

added

damping

coefficient

(Nakamera et al., 2000)

Freon

46×5 U-bend tubes, specification of actual westinghouse type-51 series steam generator.

(Not considered) based on Connors single­phase relation.

—

16-26

Damping ratio <1 %

(Feentra et al., 2000)

R-ll

Parallel / T riangular

0-0.99

—

0-100

1.1-2.9

(Pettigrew & Taylor, 2003)

Steam-water

general

overview

General overview

General

overview

General

overview

General

overview

General

overview

(Chung & Chu, 2005)

Air-water

Normal square/rotated square

Void fraction 10-95%

—

18.65-20.7

Hz

0.01-0.05

(Parsad et al., 2007)

Steam-water

general

overview

General overview

General

overview

General

overview

General

overview

General

overview

(Pascal-Ribot & Blanchet, 2007)

Air-water

Rigid cylinder

10-80%

Dia=100

mm

0-25 Hz

—

(Kakac & Bon, 2008)

Steam-water

general

overview

General overview

General

overview

General

overview

General

overview

General

overview

(Mitra et al., 2009)

Air-water / Steam-water

Normal square tube array suspended from piano wires

Void fraction 0-45%

Dia=190

mm

7.84-13.9

Hz

3.3-5.2

(Sim & Park, 2010)

—

Cantilevered flexible cylinder

3-38%

Dia=123

mm

12Hz

0.1128-

0.1154

(Chu et al., 2011)

Air-water

U-tube rotated square

70-95%

Dia=19.0

5mm

4-12 Hz

0.0038

* Results 1973-1993 (Pettigrew et alv 1973)

Table 9. Representative Published Tests on Two — Phase Flow

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