Injector Apparatus for Reheat Combustor Aft Section
Solution Overview
Problem
The efficiency of reheat combustors in power generation systems is limited by the output and emissions, particularly due to sub-optimal design constraints such as inlet temperature, emissions, and combustion reactions, which affect the overall performance and efficiency of gas turbine systems.
Innovation Solution
The introduction of an injector apparatus that delivers additional fuel and air to the aft section of a reheat combustor, allowing for late lean injection and optimizing combustion reactions, reducing emissions, and improving the temperature tolerance of the inlet, thereby enhancing the efficiency and power output of the system.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If additional fuel and air are delivered to the aft section of the reheat combustor, then combustion efficiency and power output are improved, but emissions may increase
Solution Approach 1:
The reheat combustor is divided into a fore section and an aft section, with separate fuel injection systems for each zone. The fore section receives fuel through conventional injection, while the aft section receives additional fuel through the injector apparatus positioned downstream. This segmentation allows staged combustion that improves efficiency while managing emissions by controlling where and how fuel burns in each zone.
Solution Approach 2:
The injector apparatus is positioned specifically in the aft section to deliver fuel and air locally where needed. This localized injection creates optimal combustion conditions in the downstream region, improving overall combustion efficiency and power output while the staged approach helps manage emissions by controlling the combustion environment in different spatial zones.
2Productivity
If the reheat combustor operates at higher temperatures to improve efficiency, then power output increases, but temperature tolerance constraints are violated
Solution Approach 1:
The injector apparatus is positioned downstream in the aft section, allowing fuel to be injected after the primary combustion zone. This preliminary positioning of the injection point downstream enables the fuel to mix and combust in a region where temperature management is more effective, improving efficiency without violating temperature tolerance constraints of upstream components.
Solution Approach 2:
The aft section acts as an intermediary zone between the fore section combustion and the turbine inlet. By positioning the additional fuel injection in this intermediate region, the system can manage temperature transitions more effectively, allowing higher overall efficiency while protecting temperature-sensitive components upstream through the buffering effect of the staged combustion zones.
3Productivity
If fuel injection is optimized for complete combustion, then efficiency improves, but combustion reactions may occur in undesired locations
Solution Approach 1:
The combustion process is segmented into two distinct zones: the fore section with conventional fuel injection and the aft section with additional fuel injection through the injector apparatus. This segmentation ensures that combustion reactions occur in the intended downstream location rather than upstream, maintaining proper combustion zone positioning while achieving complete combustion for improved efficiency.
Solution Approach 2:
The injector apparatus in the aft section is designed to deliver fuel and air in proportions that promote complete combustion within the downstream region. The local fuel-air mixing and combustion characteristics are optimized so that the aft section combustion serves the overall system efficiency while naturally confining reactions to the desired downstream location through proper injection timing and mixture preparation.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This solution increases the efficiency of the power generation system by optimizing combustion reactions, reducing emissions, and improving the temperature tolerance of the inlet, leading to increased power output and reduced emissions, specifically by allowing for staged combustion reactions in multiple zones.
Implementation Method 1
an injector for delivering a carrier gas and/or a portion of the fuel from the fuel supply line to the aft section
Implementation Method 2
a conduit in fluid communication with the injector, wherein the conduit delivers at least one of a fuel from a fuel supply line and a carrier gas to the injector
Data Source
AI summary
Embodiments of the present disclosure provide an apparatus including: a first injector located on a surface of a turbine nozzle of a turbine stage positioned downstream of a reheat combustor, wherein the turbine stage includes the turbine nozzle and a turbine blade row; a second injector located on a wall of the reheat combustor; and at least one conduit in fluid communication with each of the first injector and the second injector, wherein the at least one conduit delivers at least one of a fuel from a fuel supply line and a carrier gas to an aft section of the reheat combustor through at least one of the first injector and the second injector, and wherein the aft section is positioned downstream of a combustion reaction zone in the reheat combustor.