Impacts of combustion chamber location and tube bundle layout on the performance of three-pass hot-water steel boilers under the steady-state operation

Abstract

This study discusses the effects of the combustion chamber location and tube bundle layout on the performance of three-pass hot-water steel boilers under steady-state operation. For this goal, three possible nondimensional locations (S) for the combustion chamber of −0.25, 0, and 0.25, and three various nondimensional gap spaces (G/P) between the second and third passes of 1.0, 2.5, and 5.0 are investigated using inward (Layout-A) and outward (Layout-B) right triangular pass layouts. All computations are carried out for the Richardson numbers of 0.1, 1.0, and 10, and the obtained results are successfully validated against the available data in the open literature. It is found that changing the combustion chamber location greatly affects the boiler performance. Additionally, the gap space between the second and third passes and tube bundle layout have considerable influence on the heat and momentum transfer inside the boiler. It is revealed that, regardless of the Richardson number, a three-pass hot-water steel boiler constructed with S = –0.25 and G/P = 5.0 and having Layout-A for second and third passes has the maximum thermal-hydraulic performance and can be considered by boiler designers.

Keywords:

• Combustion chamber
• thermal-hydraulic performance
• three-pass hot-water steel boiler
• tube bundle