| 摘要 |
PURPOSE:To suppress the generation of dryout without increasing the supply quantity of an operating medium by providing guide ridges for diffusing and guiding the operating medium in the tube axial direction on the outer surfaces of at least those required among a plurality of heating promoting heat transfer tubes. CONSTITUTION:Concave guide ridges 25 formed along the tube axial direction are provided on the outer surfaces of porous materials 33 as the outer surfaces of heating promoting heat transfer tubes 23. An operating medium F sprayed over the uppermost heat transfer tube 23 flows down in a membrane shape along the outer surface of each heat transfer tube 23 is dispersed in the tube axial direction, and further the lower guide ridge 35 disperses the operating medium F in the tube axial direction and functions to spray the same over the subsequent stage heat transfer tube 23. In addition, guide ridges 35 on the side surfaces of the heat transfer tubes 23 perform a substantially intermediate operations of these described operations, and the operating fluid F flows down along all the heat transfer tubes 23 is uniform liquid membrane. Therefore, even in the lower heat transfer tubes 23, the generation of the dryout is suppressed. |
