Vibration damping structure for heat-transfer tube bundle

A vibration damping structure for a heat-transfer tube bundle including

• columns each composed of a plurality of heat-transfer tubes curved in a common plane and arranged in parallel to each other, the columns being arranged at an interval, the vibration damping structure comprising:
• at least one first vibration damping member disposed between a Nth column and a N+1th column so as to intersect an array direction of the columns, where N represents a natural number;
• and at least one second vibration damping member disposed between the N+1th column and a N+2th column so as to intersect the array direction,
• wherein the first vibration damping member and the second vibration damping member are disposed at different positions in an axial direction of each heat-transfer tube, and thicknesses of the first vibration damping member and the second vibration damping member in the array direction are larger than an average value of a clearance between the columns under operation, wherein the plurality of the heat-transfer tubes are respectively arranged so that an arc portion is convex upward, and wherein the first vibration damping member and the second vibration damping member are alternately arranged along the array direction so that a bent portion which is curved in an opposite direction to the arc portion corresponds to the arc portion of the plurality of the heat-transfer tubes.