Generalization of experimental data on amplitude and frequency of oscillations induced by steam injection into a subcooled pool
2015 (English)In: Nuclear Engineering and Design, ISSN 0029-5493, E-ISSN 1872-759X, Vol. 295, 155-161 p.Article in journal (Refereed) PublishedText
Steam venting and condensation into a subcooled pool of water through a blowdown pipe can undergo a phenomenon called chugging, which is an oscillation of the steam water interface inside the blowdown pipe. The momentum that is generated by the oscillations is directly proportional to the oscillations' amplitude and frequency, according to the synthetic jet theory. Higher momentum can enhance pool mixing and positively affect the pool's pressure suppression capacity by reducing thermal stratification. In this paper, we present a generalization of available experimental data on the amplitude and frequency of oscillations during chugging. We use experimental data obtained in different facilities at different scales to suggest a scaling approach for non-dimensional amplitude and frequency of the oscillations. We demonstrate that the Froude number Fr (which relates the inertial forces to gravitational forces) can be used as a scaling criterion in this case. The amplitude has maximum at Fr approximate to 2.8. There is also a strong dependence of the amplitude on temperature; the lower the bulk temperature is the higher the scaled amplitude. A known analytical theory can only capture the decreasing trend in amplitude for Fr > 2.8 and fails to capture the increasing trend and the temperature dependence. Similarly, there is a minimum of the non-dimensional frequency at Fr approximate to 6. A strong dependence on temperature is also observed for Fr> 6; the lower the bulk temperature is the higher the scaled frequency. The known analytical theory is able to capture qualitatively the general trend in frequency but not the dependence on temperature.
Place, publisher, year, edition, pages
Elsevier, 2015. Vol. 295, 155-161 p.
IdentifiersURN: urn:nbn:se:kth:diva-180990DOI: 10.1016/j.nucengdes.2015.08.031ISI: 000367413700015ScopusID: 2-s2.0-84945957802OAI: oai:DiVA.org:kth-180990DiVA: diva2:898282
QC 201601272016-01-272016-01-262016-02-08Bibliographically approved