| 摘要 |
1,194,249. Cooling discharge tubes. COMPAGNIE FRANCAISE THOMSON-HOUSTON-HOTCHKISS BRANDT. 14 Sept., 1967 [15 Sept., 1966], No. 41950/67. Heading H1D. [Also in Divisions F1 and F4] A heat transfer surface 1 applicable to electron tubes (Figs. 3-5) is formed with throats or grooves 9 extending in a direction 12 at an angle of between 45 and 90 degrees to the general direction 11 of a forced flow of liquid over the surface, each groove having a depth b greater than its width d, and a guide wall 2 being located adjacent the heat transfer surface so that the liquid flow 11 is confined between the surface and the wall. The arrangement is such that heat is transferred between the liquid and the surface by local evaporation accompanied by recondensation of the vapour in the mass of the liquid. In a typical example described the throats or grooves 9 are 2 mm. wide x 7 mm. deep the distance e of the guide wall 2 from the surface being from 0À3 to 3 mm. As shown, evaporation of the liquid takes place at zones 20-22 of progressively increasing temperature in the throat or groove, and the vapour thus formed discharges at high velocity into the main liquid stream 11 where it is condensed by turbulent admixture with the liquid. It is said that this high turbulence also ensures a liquid feed into the grooves 9 sufficient for the needs of vaporization. The wall 1 may be cylindrical in which case the throats may comprise annular, helical, or longitudinal grooves therein on either the convex or concave surface of the cylinder. In cross-section, the base of the throat may be straight, or rounded (Figs. 3-5), or the crosssection may be triangular (Figs. 6/7). Guide vanes (33, 34, Figs. 3/4) may be attached to the wall 1 or to the wall 2 to direct liquid flow in the space 19 between the walls. Two grooved heat transfer walls may be disposed face to face, each serving as a guide wall for the other. Applications particularly described include an electron tube (Figs. 3/4) and an electron beam tube (Fig. 5) in which the wall constitutes the tube anode. Also described in connection with electron tubes are the provision of an elastic hollow body 37 (Fig. 4) in the liquid stream to damp out abrupt variations in pressure which may occur therein.
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