摘要 |
This invention provides a thin wall header fabricated from a nickel-base superalloy, UNS N06626, for the solar absorption panels in a molten nitrate salt solar central receiver. The thin wall header is obtained by using multiple flow distribution nozzles to yield the smallest diameter header having uniform flow distribution for the panel tubes while providing enough space to butt weld the tubes to the nozzles with an automatic orbital weld head and avoid overlapment of the nozzle reinforcement regions. This small diameter combined with the high allowable tensile stress of UNS N06626 results in a thin wall header. The thin wall small diameter UNS N06626 header with its low thermal expansion coefficient and small temperature gradients and differentials during cloud cover induced molten salt temperature transients yields low thermal strains in the tube nozzle to header region. The nozzles may be formed by direct extrusion from the header wall or by insert-welding a machined nozzle into the header wall. Either construction, combined with the materials excellent thermal strain fatigue resistance eliminates the need to furnish costly and complex thermal protection devices for this region.
|