[en] This report is an evaluation report of the CCTF Core-II test C2-AA2 (Run 58). In this test the ECC water was injected into the downcomer as well as into the intact cold legs in order to investigate characteristics of thermo-hydrodynamic behavior in a downcomer injection test. For this purpose, the test conditions were determined to be the same as those for the base case test (Test C2-4 (Run 62)) except for the ECC water injection locations. The ECC water injection location in the base case test was only the cold leg. Comparing the data of the present test with those of the base case test, the following results are obtained. (1) The present test experienced a significant periodic oscillation. (2) Thermal equilibrium by mixing of ECC water and steam flowing in the intact loops was not established at the downcomer in the present test, and hence, downcomer fluid temperature was observed to be subcooled and lower than in the base case test. (3) Fluid temperature at the core inlet was higher than in the base case test. Quenching of heater rods were slightly later than in the base case test. (4) Although thermo-hydrodynamic behavior through the system was oscillatory in the present test, average values of the oscillatory data were nearly identical to those of the base case test except for the differences mentioned in items (2) and (3) above. This suggests, for analysis or prediction of core cooling for the downcomer injection case, it would be possible to use the same models, methods or computer codes as used for the cold leg injection case with adding a modification on predicting the fluid temperature at the core inlet. (J.P.N.)