Cooling of Electron Beam Extraction Window

Through study on stress of titanium foil of extraction window, geometric shapes of titanium foil at atmospheric pressure were determined; thus incident angles of electron beam on titanium foil and the corresponding penetration distance were calculated, thereby the relationships between distributions of energy loss of electron beam on titanium foil and the yield strength of the titanium foil, the thickness as well as the span were obtained. Through analysis on heat dissipation capability of heat transfer and heat radiation of titanium foil itself, it's concluded that wind-cooling is the best way to increase the output capability of extraction window. Combined with numerical simulation, study on the relationships among heat dissipation capability of wind-cooling, air velocity and curvature radius of titanium foil is stressed, through which it's concluded that reflux zone may exist at conventional wind-cooling structure and turn out to be a weak spot for titanium foil cooling and the effect of reflux section needs to be removed by means of optimization of the structure. (authors)