MODIFIED CHOKE FLOW CRITERION FOR THE TWO-PHASE TWO-FLUID MODEL
A choked condition exists when mass flow rate becomes independent of the downstream conditions. In other words, no information can propagate in the upstream direction under this condition. The real part of the solution of the characteristic equation for the model represents velocity of the signal propagation and the imaginary part is the growth (or decay) rate of that signal. Therefore, if the real part of these eigenvalues is positive then no signal propagates in the upstream direction (choosing downstream direction to be the positive direction) resulting in the choke flow. In order to develop the choke criterion, a non-dimensional form of the characteristic equation is derived for the standard two-phase two-fluid model. The equation is in the terms of a slip Mach number Ms. It can be shown that the slip Mach number is small for many applications including nuclear reactor safety simulations. The eigenvalues of the characteristic equation are obtained as a power series expansion about the point Ms = 0. These eigenvalues are used to develop a choking criterion for the compressible two-phase flows.
- Research Organization:
- Idaho National Lab. (INL), Idaho Falls, ID (United States)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- DE-AC07-99ID-13727
- OSTI ID:
- 957541
- Report Number(s):
- INL/CON-09-15438; TRN: US1000632
- Resource Relation:
- Conference: International Conference on Mathematics, Computational Methods & Reactor Physics (M&C 2009),Saratoga Springs, New York,05/03/2009,05/07/2009
- Country of Publication:
- United States
- Language:
- English
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