1. Bologna on 28 May 2008 – IP EUROTRANS WP1.51 IE - Institute for Energy Petten - The Netherlands http://ie.jrc.ec.europa.eu/ http://www.jrc.ec.europa.eu/ Joint Research Centre (JRC) SGTR and SGTL

2. Bologna on 28 May 2008 – IP EUROTRANS WP1.52 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

3. Bologna on 28 May 2008 – IP EUROTRANS WP1.53 Pool design and SGTR, SGTL SGTR SGTL 15..25 MPa, 330..500 o C 0.3 MPa, 400..500 o C Steam Generator Tube Rupture (SGTR) SGTR at PWR ~10 3 –10 4 liter/hour Steam Generator Tube Leakage (SGTL) SGTL Rate: 10 - 10 3 liter/day Leakage less than 1 liter/day – allowed in normal operation of PWR From P. Kudinov

4. Bologna on 28 May 2008 – IP EUROTRANS WP1.54 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 o C) into lead at 0.8 MPa liquid water No explosion reported. Limited expansion. From P. Kudinov

5. Bologna on 28 May 2008 – IP EUROTRANS WP1.55 Size distributions of water/steam droplets Beznosov et al, 2005 From P. Kudinov

6. Bologna on 28 May 2008 – IP EUROTRANS WP1.56 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

7. Bologna on 28 May 2008 – IP EUROTRANS WP1.57 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

8. Bologna on 28 May 2008 – IP EUROTRANS WP1.58 Vapor bubbles formation and transport phenomena Terminal speed of rising bubbles with d max ~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 Mendelson: Lehrer: From P. Kudinov

9. Bologna on 28 May 2008 – IP EUROTRANS WP1.59 Stream lines and flow field Stream lines during normal operation Flow field during normal operation

10. Bologna on 28 May 2008 – IP EUROTRANS WP1.510 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.

11. Bologna on 28 May 2008 – IP EUROTRANS WP1.511 SGTR experiment The bunker (at FZK funded by JRC) where the experiment be performed

12. Bologna on 28 May 2008 – IP EUROTRANS WP1.512 Experimental facility

13. Bologna on 28 May 2008 – IP EUROTRANS WP1.513 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, 160  C) into Pb of 340  C. 3. Injection of 3 liters supercritical steam (240 bar, 400  C into Pb of 480  C. Simulating break of 8 pipes of the EFIT or ELSY design.

14. Bologna on 28 May 2008 – IP EUROTRANS WP1.514 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.