Thermal transient simulation tests of a sodium valve

The feasibility of thermal transient testing of sodium components using a fluid other than sodium is considered. Simulation of thermal transient conditions that may exist in the sodium system is considered to be, in general, achievable in a special test fixture, if the thermal and hydraulic conditions of the fluid to be used are properly selected. This feasibility is demonstrated for the 28 in. FFTF hot-leg isolation valve by introducing a high-speed gaseous nitrogen flow into an annulus formed by the valve body and a cylindrical pipe insert. The structural wall temperature distributions were estimated first for the sodium system, and the simulation was established by equating the transient heat transfer rates as a function of time at key locations in both real sodium and simulating nitrogen systems. Remarkably good simulation test results were achieved.