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Bologna on 28 May 2008 – IP EUROTRANS WP1.5 1
IE - Institute for EnergyPetten - The Netherlands
http://ie.jrc.ec.europa.eu/
http://www.jrc.ec.europa.eu/
Joint Research Centre (JRC)
SGTR and SGTL
Bologna on 28 May 2008 – IP EUROTRANS WP1.5 2
Overview
• Background to SGTR and SGTL
• Present status of cooperation on SGTL between KTH and JRC
• SGTR experiments to be executed at FZK on behalf of JRC
• Conclusions
Bologna on 28 May 2008 – IP EUROTRANS WP1.5 3
Pool design and SGTR, SGTL
SGTR SGTL
15..25 MPa, 330..500 oC
0.3 MPa, 400..500 oC
Steam Generator Tube
Rupture (SGTR)
SGTR at PWR ~103–104 liter/hour
Steam Generator Tube
Leakage (SGTL)
SGTL Rate: 10 - 103 liter/day
Leakage less than 1 liter/day – allowed in normal operation of PWRFrom P. Kudinov
Bologna on 28 May 2008 – IP EUROTRANS WP1.5 4
Liquid fraction
Beznosov et al (2005)
A.V. Beznosov, ”Experimental Studies of the Characteristics of Conatct Heat Exchange between lead Coolant and the Working Body”, Atomic Energy, 98(3), 2005
“a steam–water mixture, and 100–350°C, 1–25 MPa steam were bubbled through 0.6–2 mm in diameter openings (tube 14x2 mm), under a layer of lead ranging in thickness from 100 to 3000 mm, at temperatures 350–600°C”
Water injection (at 30 MPa, 335 oC) into lead at 0.8 MPa
liquid water
No explosion reported.Limited expansion.
From P. Kudinov
Bologna on 28 May 2008 – IP EUROTRANS WP1.5 5
Size distributions of water/steam droplets
Beznosov et al, 2005
From P. Kudinov
Bologna on 28 May 2008 – IP EUROTRANS WP1.5 6
Life time of small droplet
Guido Bleiker and Eckehard Specht Film evaporation of drops of different shape above a horizontal plate International Journal of Thermal Sciences, Volume 46, Issue 9, September 2007, Pages 835-841
Time scale is ~10s of seconds for droplets ~1mm in diameter
From P. Kudinov
Bologna on 28 May 2008 – IP EUROTRANS WP1.5 7
Vapor bubbles formation
Evaporation of water droplet in a bubble will lead to growth of bubble diameter.
Big bubbles most likely will not be stable due to high We number and high turbulence level.
As a result we will have larger number of middle size bubbles up to 10 mm in diameter.
From P. Kudinov
Bologna on 28 May 2008 – IP EUROTRANS WP1.5 8
Vapor bubbles formation and transport phenomena
Terminal speed of rising bubbles with dmax~10mm is ~0.2-0.3 m/s
Importance of resolution of 3D structure of the coolant flow for reliable prediction of void flux into the core
Terminal velocity
0.00
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.1 1 10 100d, mm
m/s
Jamialahmadi
Mendelson
Lehrer
Mendelson:
Lehrer:From P. Kudinov
Bologna on 28 May 2008 – IP EUROTRANS WP1.5 9
Stream lines and flow field
Stream lines during normal operation
Flow field during normal operation
Bologna on 28 May 2008 – IP EUROTRANS WP1.5 10
Following calculation step
Small leakage is assumed in this study.
Next step will be to introduce individual steam bubbles at different locations in the HX. These bubbles will be followed along their trajectories.
Different sizes of bubbles will be studied.
The probability that bubbles reach the core will be estimated.
Bologna on 28 May 2008 – IP EUROTRANS WP1.5 11
SGTR experiment
The bunker (at FZK funded by JRC) where the experiment be performed
Bologna on 28 May 2008 – IP EUROTRANS WP1.5 12
Experimental facility
Bologna on 28 May 2008 – IP EUROTRANS WP1.5 13
Experiments to be performed
1. Steam of 200 bar pressure released into water simulating break of 8 pipes – will be performed during summer of 2008
2. Injection of 3 liters of superheated steam (25 bar, 160C) into Pb of 340C.
3. Injection of 3 liters supercritical steam (240 bar, 400C into Pb of 480C. Simulating break of 8 pipes of the EFIT or ELSY design.
Bologna on 28 May 2008 – IP EUROTRANS WP1.5 14
Summary
Cooperation between KTH and JRC concerning studies on small leakages. Results from this study expect this autumn.
SGTR experiments will be performed at FZK. The first one will be performed this summer.