Patent ID: 8290112
Filing Date: 2012-10-16
Classification: G21C,Y02E

Abstract:
1. A boiling water nuclear reactor multi-stage jet pump mixer assembly comprising: an inlet body having a discharge end, the inlet body configured to receive a drive flow of a motive fluid; a first throat structure arranged in proximity to the discharge end of the inlet body so as to provide a first entrainment entrance between the discharge end and the first throat structure, the first throat structure configured to receive the motive fluid from the inlet body and a first entrained flow of suction fluid external to the inlet body, the first throat structure having a body with a first end and an opposing second end, the first end being proximal to the discharge end of the inlet body, the first throat structure having an entrance opening at the first end and a tapered exit opening at the second end, the exit opening being smaller than the entrance opening; a second throat structure surrounding the first throat structure so as to provide a second entrainment entrance between the first throat structure and the second throat structure, the second entrainment entrance configured to receive a second entrained flow of suction fluid external to the inlet body; the entire first throat structure positioned within the second throat structure; and at least one first stage nozzle disposed on the discharge end of the inlet body and configured to discharge the motive fluid from the inlet body into the first throat structure at a first velocity sufficient to create a first pressure drop that induces the first entrained flow of suction fluid into the first entrainment entrance, the discharged motive fluid and first entrained flow of suction fluid forming a first mixed flow exiting the first throat structure at a second velocity sufficient to create a second pressure drop that induces the second entrained flow of suction fluid through the second entrainment entrance.