TPX heating and cooling system

TPX, while having primarily super-conducting coils that do not require water cooling, still has very significant water cooling requirements for the plasma heating systems, vacuum vessel, plasma facing components, diagnostics, and ancillary equipment. This is accentuated by the 1000-second pulse requirement. Two major design changes, which have significantly affected the TPX heating and cooling system, have been made since the conceptual design review in March of 1993. These are (1) changing the vacuum vessel neutron shielding configuration, and (2) reducing the vacuum vessel operating temperature. This paper will discuss these changes and review the current status of the conceptual design. In all, six different heating and cooling supply requirements (temperature, pressure, water quality) for the various TPX components must be met. This paper will detail these requirements and provide an overview of the heating and cooling system design while focusing on the ramifications of the TPX changes.