원문정보
초록
영어
Thermoacoustic oscillations (TAOs) could be often observed in liquid helium cryogenic system especially in half-open tubes. These tubes have closed warm end (300K) and open cold end (usually 4.4K). This phenomenon significantly induces additional heat load to cryogenic system and other undesirable effects. This work focuses on using computational fluid dynamics (CFD) method to study TAOs in liquid helium. The calculated physical model, numerical scheme and algorithm, and wall boundary conditions were introduced. The simulation results of onset process of thermoacoustic oscillations were presented and analyzed. In addition, other important characteristics including phase relation and frequency were studied. Moreover, comparisons between experiments and the CFD simulations were made, which demonstrated thevalidity of CFD simulation. CFD simulation can give us a better understanding of onset mechanism of TAOs and nonlinear characteristics in liquid helium cryogenic system.
목차
1. INTRODUCTION
2. CFD MODELING FEATURES
2.1. Numerical model details
2.2. Tube wall boundary condition analysis
3. CFD RESULTS AND DISCUSSION
3.1. Self-excited thermoacoustic oscillation
3.2. Phase and frequency analysis
4. COMPARISON WITH EXPERIMENTAL RESULTS
4.1. Experimental setup for thermal insulation tube
4.2. Comparison with thermal insulation tubes
4.3. Comparison with non-thermal insulation tube
5. CONCLUSIONS
ACKNOWLEDGMENTS
REFERENCES