Ph.D. thesis proposal by: Nishant Jain

When: 07/24/2017 (Monday), 11AM-12:00PM

Where: Montgomery Knight building, conference room# 317

Staged combustion offers many advantages in high performance aero-propulsion and power generation applications that demand increasingly robust gas turbine engines with reduced emissions. Air-staged combustors primarily rely upon rapid mixing and rapid combustion which occurs in a confined environment with multiple large jets carrying significant amounts of mass and momentum into a high temperature vitiated crossflow. The proposed thesis focuses on elucidating the mixing and combustion processes under conditions relevant to applications in non-premixed (Rich-Quench-Lean, RQL) and premixed (Lean-Quench-Lean, LQL) staged combustors. To this effect, experimental and analytical investigations will be performed in a simplified atmospheric laboratory setup using geometries, air split ratios, jet configurations and other flow parameters that are relevant to practical applications.

With the goal of determining mixing and flow field characteristics that are unique to highly confined multiple jets in crossflow, high speed planar and stereo PIV techniques will be employed. The thesis will examine the impact of jet-jet and jet-wall interactions on mixing for two jet configurations, namely, parallel jets and staggered-opposed jets. Moreover, high speed OH* chemiluminescence imaging of highly confined reacting jets in a high temperature, vitiated crossflow will be performed to understand the controlling flame characteristics such as flame stabilization mechanisms, liftoff height and burnout distance. Reduced order chemical kinetic modeling (e.g., autoignition and consumption-based flame speed analysis) will also be used to interpret the results obtained from the flame measurements. Essentially, the temporally and spatially resolved velocity and mixing results will be used together with the high speed chemiluminescence and reduced order modeling to investigate the interplay of flow and combustion characteristics in staged combustion architectures.

Proposal committee members:

• Dr. Jerry M. Seitzman (advisor)
• Dr. Jechiel I. Jagoda
• Dr. Timothy C. Lieuwen