Heat exchanger, boiler, and setting method for heat exchanger

A heat exchanger comprising:

• a plurality of cylindrical heat transfer tubes extending in a direction which crosses a flowing direction of a combustion gas, the plurality of heat transfer tubes being disposed at a predetermined disposition interval along the flowing direction, such that heat exchange is performed between a fluid flowing in the plurality of heat transfer tubes and the combustion gas;
• and
• a swirl preventing section disposed in contact with a downstream side outer circumferential surface, relative to the flowing direction, of each of the plurality of heat transfer tubes and configured to prevent a swirl of the combustion gas from occurring near the downstream side outer circumferential surface,
• wherein the swirl preventing section is disposed in contact with both
• the downstream side outer circumferential surface of a first heat transfer tube among the heat transfer tubes, and
• an upstream side outer circumferential surface, relative to the flowing direction, of a second heat transfer tube among the heat transfer tubes, the second heat transfer tube being disposed adjacent to the first heat transfer tube on a downstream side of the first heat transfer tube in the flowing direction.

A heat exchanger comprising:

• a plurality of cylindrical heat transfer tubes extending in a direction which crosses a flowing direction of a combustion gas, the plurality of heat transfer tubes being disposed at a predetermined disposition interval along the flowing direction, such that heat exchange is performed between a fluid flowing in the plurality of heat transfer tubes and the combustion gas;
• a swirl preventing section disposed in contact with a downstream side outer circumferential surface, relative to the flowing direction, of each of the plurality of heat transfer tubes and configured to prevent a swirl of the combustion gas from occurring near the downstream side outer circumferential surface;
• and
• a holding section disposed between a pair of the heat transfer tubes, the pair of the heat transfer tubes being adjacent to each other in the flowing direction,
• wherein the swirl preventing section includes a fireproof material including at least any one of SiO2, Al2O3, and SiC, and the holding section is configured to hold the fireproof material, and wherein the holding section includes
• a first bar-like member made of metal, both end portions of which are welded to the pair of heat transfer tubes, and
• a second bar-like member made of metal welded to the first bar-like member and disposed to cross the first bar-like member.

A boiler comprising a heat exchanger that performs heat exchange with combustion gas generated in a furnace,

• wherein the heat exchanger includes:
• a plurality of cylindrical heat transfer tubes extending in a direction which crosses a flowing direction of a combustion gas, the plurality of heat transfer tubes being disposed at a predetermined disposition interval along the flowing direction, such that heat exchange is performed between a fluid flowing in the plurality of heat transfer tubes and the combustion gas;
• and
• a swirl preventing section disposed in contact with a downstream side outer circumferential surface, relative to the flowing direction, of each of the plurality of heat transfer tubes and configured to prevent a swirl of the combustion gas from occurring near the downstream side outer circumferential surface, the swirl preventing section being disposed in contact with the downstream side outer circumferential surface in a range of 120° or more and 180° or less along the downstream side outer circumferential surface.