1D Thermo-fluid Model of a DLE Combustion Chamber for Heavy-duty Gas Turbine - part 2

Dry Low NOx (DLN) combustors are mainly adopted in heavy-duty gas turbines due to their ability to achieve low emissions through lean-premixed operation without requiring water or steam injection. This research focuses on a DLN1.0 with a can-annular architecture and a venturi-stabilised reaction zone. Its operability is limited by a “four-sided box” that balances NOx emissions, CO burnout, stability and dynamics. These features drive the development of reduced-order tools that accurately simulate the physical phenomena with low computational effort. This study develops a one-dimensional thermo-fluid model of a DLN1.0 combustor for power generation. Given the 3D model of the combustor, each component and subcomponent is represented by the geometry of the actual elements and the associated pressure losses. The air and fuel paths are initially validated independently against flow tests of the respective circuits. The components are then interconnected into a system network to simulate air–fuel interactions that influence premixing quality and stage-split effects. Therefore, reaction modules are integrated in the 1D flow network to simulate a combustion phase consistent with lean-premixed DLN operation. The combustion products are obtained (CO2, H2O, O2, CO) and NOx, providing emission estimation for the operating points of interest. Compared with three-dimensional CFD, the resulting model is less computationally demanding and thus suited to rapid parametric studies — such as fuel-split, effective areas and Delta p targets — relevant for tuning and maintenance.