Abstract
A cryogenic hydrogen circulation system to cool cryogenic hydrogen moderators for the spallation neutron source in J‐PARC has been designed. This system consists of a helium refrigerator system and a hydrogen circulation system. The refrigeration capacity required for the cryogenic system is specified to be around 6 kW at 17 K. The hydrogen circulation system is composed of a hydrogen‐helium heat exchanger, two circulation pumps, multiple transfer lines, three moderator vessels, an Ortho‐Para hydrogen converter, an accumulator, a heater and others. The system adopts a centrifugal‐type hydrogen pump that can circulate the cryogenic hydrogen (20 K, 0.5 to 1.5 MPa) with the mass flow up to 162 g/s through the three moderators. This forced‐flow circulation can remove the nuclear heating from the moderators and can keep the temperature difference through the moderators within 3 K. The Ortho‐Para hydrogen converter will be installed to maintain the Para‐hydrogen concentration of more than 99% at the inlet of the moderators. For the pressure changes due to the proton beam being turned on and off, we will prepare an accumulator and a heater, which is called a hybrid pressure control. The cryogenic system has been designed with safety concepts that protect the public.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
