Dynamic characteristics of the cryogenic hydrogen system for a spallation neutron source at J-PARC

Tatsumoto, Hideki; Aso, Tomokazu ; Kato, Takashi; Otsu, Kiichi

To mitigate pressure fluctuation caused by the load, a pressure control system is a necessary requirement. Accordingly, a control system was designed and installed, using a heater and an accumulator. Changes in pressure caused by operation of a 120-kW and a 302-kW proton beam were studied. It was confirmed that the pressure control system was effective in mitigating the pressure fluctuation caused by the load. A simulation code was also developed and the pressure rise behavior and the accumulator variation were studied. The simulation results indicated good agreement with the experimental data within 10%. The pressure fluctuation for a 1-MW proton beam was predicted to be 33.9 kPa, which is lower than the allowable pressure rise of 0.1 MPa, and produced an accumulator variation of 11.35 mm. We believe that the pressure control system is effective for use with the operation of a 1-MW proton beam.