| 摘要 |
PURPOSE:To improve heat transfer performance by a method wherein a partitioning cylinder, surrounding the periphery of bundle of spiral heat transfer tube arranged in an annular space between the assembled return pipe of secondary fluid and the inner surface of a vertical type vessel and precluding the bypass flow of primary flow, is provided with protuberances and recesses on the inner surface thereof. CONSTITUTION:A plural stages of spiral fins are provided on the inner surface of the partitioning cylinder 13, a flow path is narrowed by the fins to increase a resistance, the bypass flow ascended along the inner surface of the partitioning cylinder 13 is suppressed and the heat transfer efficiency is improved. On the other hand, high-temperature primary gas 1 passes between the heat transfer tubes 4 arranged in the partitioning cylinder 13 and is discharged to the outside from an outlet nozzle 5 after effecting heat exchange between the secondary gas in the heat transfer tubes 4, however, the upper part of the partitioning cylinder 13 is closed, therefore, the bypass flow generated between the heat transfer tubes 4 and the vertical type vessel 3 is suppressed, the high-temperature primary gas 1 ascends between the heat transfer tubes 4 under a condition that it is distributed uniformly substantially and the heat transfer efficiency may be improved. |
