Theoretical Study for Accelerated Two-Phase Flow : (1), Constant-area Flow

抄録

In the analysis of an accelerated two-phase flow, the phase change in thermal equilibrium condition, wall friction, interphase friction caused by the difference between two velocities and the entropy increase are considered. Some numerical calculations are made for the conditions of Ogasawara's experiments of a steam-water critical flow from a long constant cross-section pipe. The numerical results are in good agreement with the experimental ones, i.e. the pressure gradient close to the exit plane of the test pipe and the critical flow rates. Further numerical results show that, of the total pressure drop caused by friction and acceleration, the proportion attributable to friction approaches zero in the condition of a critical flow at the exit plane and that the critical flow rate is not determined simply in terms of pressure and quality at the critical flow condition but in the approaching process to critical flow condition.