Session: 11-01: Combustor Heat Transfer

Paper Number: 151891

Thermo-Structural Design of an Air-Cooled Rotating Detonation Combustor for Gas Turbine Integration 

Rotating Detonation Combustion is a promising technology that significantly increases thermodynamic efficiency and reduce the footprint of propulsion and power generation applications. In this combustor architecture, a detonation wave propagates around an annular chamber at frequencies in the order of 1 to 10 kHz. Considerable fluctuations in the flow properties are present as a result of the detonation wave motion. This strong, unsteady behavior, together with the extreme power density resulting in a compact combustor size, poses considerable challenges for thermal management. The aim of this work is to design an air-cooled rotating detonation combustor suitable for integration into the Rolls-Royce M250-C40B gas turbine engine. A pressure vessel-liner convection cooling architecture was selected to circumvent the unexplored influence of film cooling on the detonation physics and operability of the combustor; while a transition element was integrated to introduce dilution airflow and to damp the flow oscillations. Initially, a 1D thermal model, based on Bartz’s Nusselt number correlation, was conceived to enable rapid evaluation of different materials, temperature profiles, geometric parameters and to extract heat fluxes on the combustor walls. The results from the 1D analysis serve as the boundary conditions for the geometrical design and computational assessment of the transition element, performed using Reynolds-averaged Navier-Stokes simulations. The numerical predictions are compared to the engine turbine inlet conditions. Subsequently, transient thermo-structural FEA analyses were performed for the combustor and transition element components to evaluate the most suitable materials and cooling designs. The requirement to maximize instrumentation while keeping adequate safety factors led to the exploration of remarkably different concepts with stainless steel, copper- and nickel-based alloys, providing a varied response to thermal loads due to the contrast in thermal conductivity and yield strength. Finally, a Harmonic Response Analysis was conducted to address the impact of fluctuating pressure loads, inherent to the detonation wave physics, on the combustor liner walls and its resonance modes.

Presenting Author: Andrea Ruan Purdue University

Presenting Author Biography: Andrea is a PhD candidate at Purdue University. During his MS degree, his research focused on the experimental performance characterization of high-pressure turbines. Now, his work is directed at rotating detonation combustor performance and operability as well as integration with a gas turbine engine.

Authors:

Andrea Ruan Purdue University
Sergio Grasa Purdue University
Rohan Gejji Purdue University
John Grunenwald North Carolina State University
Carson Slabaugh Purdue University
Guillermo Paniagua Purdue University