Simulation of a hydraulically controllable reactor coolant pump seal

A hydraulically controllable mechanical seal for a nuclear reactor coolant pump (RCP) is under development. Its purpose is to correct excessive or insufficient leakage through RCP seals, a current expensive problem. The non-rotating seal face contains an annular cavity, filled with pressurized fluid. By changing the pressure within the cavity, the deformation and geometry of the face can be changed. Since the face geometry determines the thickness of the lubricating film between the two seal faces and the leakage rate, the leakage rate can be controlled. Simulations indicate that the hydraulically controllable seal provides sufficient control to address many abnormal leakage rate scenarios.