| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an amplifying nozzle capable of varying the amount of an unreacted hydrogen gas in a hydrogen gas circulating passage jetted from the amplifying nozzle into a fuel cell stack. <P>SOLUTION: In this amplifying nozzle 4, a second fluid is supplied from the direction generally perpendicular to the flowing direction of a main flow passage 19 in which a first fluid flows to the main flow passage through an auxiliary flow passage joined to the main flow passage and an orifice 22 to build up the mixed fluid of the first and second fluids. The amplifying nozzle comprises an orifice varying means capable of reducing the opening areas of the jetting ports 22A, 23A of the orifice 22 smaller than the diameter of the main flow passage and increasing and decreasing stepwise. The orifice varying means has at least two large and small jetting ports 22A, 23A with the opening areas different from each other, a first flow passage 24 joined to the auxiliary flow passage 21 and joined to the larger jetting port 22A, a second flow passage 25 joined to the auxiliary flow passage 21 and joined to the smaller jetting port 23A, and a three-way valve 26 supplying the second fluid selectively to the first flow passage 24 or the second flow passage 25. <P>COPYRIGHT: (C)2007,JPO&INPIT |
