EVALUATION OF POROUS-MEDIA HEAT-EXCHANGERS FOR FUSION APPLICATIONS

Several types of porous media heat exchangers are being evaluated for use infusion applications. Broadly, these devices can be classified as capillary-pumped (heat pipes) or mechanically-pumped heat exchangers. Monel/water thermosyphon heat pipes with a porous metal wick are bein g evaluated for use in Faraday shields. A subscale prototype has been fabricated and initial tests at Oak Ridge National Laboratory have sho wn favorable results. Alkali metal heat pipes have demonstrated absorb ed heat flux capability of over 1000 MW/m(2). An advanced gyrotron mic rowave cavity is being developed that uses water cooling in a mechanic ally-pumped copper porous metal heat exchanger. Tests on a prototype d emonstrated absorbed heat flux capability in excess of 100 MW/m(2). Po rous metal heat exchangers with helium, water, or liquid metal coolant s are being evaluated for plasma-facing component cooling. Tests on a helium/copper porous metal heat exchanger demonstrated absorbed heat f lux capability in excess of 15 MW/m(2). Applications, conceptual desig ns, fabricated hardware, and test results are summarized.