[en] A full-scale, Zircaloy-clad, simulated BWR fuel Bundle was tested under simulated loss-of-coolant conditions. The flow area at the bundle midplane was severely restricted by mechanical means so the effect of an exaggerated flow blockage on emergency core cooling effectiveness could be determined. Because of the mechanical conditions imposed on this bundle a region of systematic, concentrated bowing developed below the blockage during the experiment. This artificially imposed condition is unique to this test bundle and is not representative of a BWR fuel bundle under postulated LOCA conditions. The extent of the flow area restriction, the temperature response, and the oxidation of the bundle cladding in both the blocked and bowed region are described and discussed. It is shown that the presence of a high degree of blockage does not adversely affect emergency core cooling effectiveness above or below the blockage. It is also shown that the systematic, concentrated rod bowing imposed in this test can lead to a predictable degradation of heat transfer in the region of maximum bowing