Design study of cooling water system for a large scale linear collider

A distributed cooling water system was designed for a large scale linear collider. It consists of a large number of small cooling water units and several main cooling systems. One small unit is installed for each RF unit of the main linac. The heat removed from the accelerator is transferred from the small unit to the main cooling system through a heat exchanger and moved to a cooling tower outside the accelerator tunnel. The fine temperature control is carried out in each small unit by utilizing waste heat from klystrons and a small electric heater. A prototype unit was made and has shown that the temperature of cooling water can be controlled within /spl plusmn/0.03/spl deg/C.