| 摘要 |
PURPOSE:To make a heat exchanger of small-size and to improve an efficiency of its operation by a method wherein a pipe with helical fins is arranged at the inner circumference of a casing being contcted to the outer circumference of the fins in the heat exchanger for use in recovering heat in steam generator to the boiler refilling water and then the drain is fed into the pipe and the refilling water is supplied to the outside of the pipe. CONSTITUTION:A drain passage pipe 20 with helical fins 16 is arranged in such a way as their outer circumferences are contacted to the inner circumference of the cylindrical casing 13, resulting in making a heat exchanger 5. With this arrangement, the drain is introduced or fed into the pipe 20 at the upper part thereof and then the boiler refilling water 18 is fed into the casing 13. The water stored in the refilling water passage 21 accepts the heat from the drain 20 to raise its temperature and then the hot water is collected at the upper part of the drain pipe. Then, a feeding of the refilling water 18 pushes the hot water 19 out of the pipe. With this arrangement, the refilling water is transformed into a disturbed flow by the helical fins 16, resulting in making an improved thermal efficiency as well as manufacturing a small-sized heat exchanger. |
