PROBLEM TO BE SOLVED: To easily stabilize a flow rate of a heating medium flowing through a heat channel.SOLUTION: A flow rate-stabilizing means to stabilize the flow rate of a heating medium flowing through a heat channel 22 is mounted in at least one of a radially outward passage 20, a radially inward passage 21 and the heat channel 22. The flow rate-stabilizing means includes a supply opening 30 formed in either of the radially outward passage 20 and the radially inward passage 21 for supplying the heating medium to the passage, and a discharge opening 31 formed in the other of the radially outward passage 20 and the radially inward passage 21 in which the supply opening 30 is not formed for discharging the heating medium from the passage. The flow rate-stabilizing means further includes a squeeze part 33 formed in each heat channel 22, and having the same cross-sectional area.
展开▼
