Demonstration of Inter-Turbine Burners for Part-Power Fuel Efficiency Improvements

Gas turbine engines using multistage turbine sections have the inherent disadvantage of temperature loss through the turbine section. This occurs when each successive turbine stage extracts energy from the superheated mass airflow. The result is limited energy potential due to the first stage turbine temperature limits. An inter-turbine burner (ITB) would be able to utilize constant temperature burning through the turbine module by adding burners between the turbine stages. ITB’s improve part-power efficiency while allowing for high fuel efficiency at maximum power through the use of its reheat cycle. ITBs' used in low cost UAV type engines allow for the use of less expensive lower temperature materials, in multiple stages, yet extract more energy from the airflow. Spytek Aerospace plans to demonstrate the feasibility of adding an ITB to an existing Spytek Aerospace engine. The ITB will be adapted from the Ultra-Compact combustor developed by the Air Force Propulsion Directorate. The major areas to be addressed will be the ability to provide air into the primary burn zone of the ITB to sustain combustion and the ability to successfully entrain the combustion products from the ITB combustor into the main stream flow without causing undue restrictions or hot streak problems.