RESEARCH PAPERS: Phase Change and Multiphase Heat Transfer

Analysis of Coupled Nuclear/Thermal Instabilities of Two-Phase Flows in Parallel Boiling Channels

[+] Author and Article Information
M. Uehiro, Y. F. Rao, K. Fukuda

Department of Nuclear Engineering, Kyushu University, Fukuoka 812, Japan

J. Heat Transfer 121(4), 916-923 (Nov 01, 1999) (8 pages) doi:10.1115/1.2826082 History: Received July 25, 1996; Revised June 02, 1999; Online December 05, 2007


An analytical model is proposed to study the two-phase flow instabilities of in-phase and out-of-phase modes in parallel boiling channels. This model takes into consideration the interaction between channels with different void fraction variations by modeling the diffusion of neutrons. Linear stability analysis in the frequency domain is performed to obtain stability boundaries and flow oscillation modes. In the case of parallel two channels, two types of stability boundaries are found to exist on the stability map; one for the instability of the in-phase mode and the other for that of the out-of-phase mode respectively. For a certain range of the void-reactivity coefficient, the void-reactivity feedback loop is found to be unstable in a certain region on the stability map, which has an effect on the stability of the in-phase mode. The interaction between channels affects the instability of the out-of-phase mode. The results are also obtained for the case of three and four channels. It is found that the channels having stronger interaction between them are more likely to oscillate in-phase with each other, while those having weaker interaction are more likely to oscillate out-of-phase with each other.

Copyright © 1999 by The American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.





Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In