| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To obtain sufficient heat exchanging performance of a double tube used as a heat exchanger having a spiral heat exchange passage constituted between an inner tube provided with spiral irregularities and an outer tube fitted around the inner tube. <P>SOLUTION: A double tube is used as a heat exchanger having a spiral heat exchange passage R1 constituted between an inner tube 1 with spiral irregularities 11 and an outer tube 2 fitted around the inner tube 11. Protrusions 11a of the irregularities 11 of the inner tube 1 are brought into abutment with an inner wall of the outer tube 2. The irregularities 11 is not provided to a part of the inner tube 1 which is bent to become a bent part. <P>COPYRIGHT: (C)2013,JPO&INPIT</p> |
