Session: 06-03 Pressure Gain Combustion II

Paper Number: 128674

128674 - Detailed Sliding-Mesh Computation of Turbulent Jet Ignition and Combustion in a Wave Rotor Combustor With Stationary Pre-Chamber 

This work applies detailed chemical and computational fluid dynamic simulation to investigate the ignition and combustion processes in a highly instrumented experimental wave rotor combustor that used a stationary pre-combustion chamber to produce a traversing hot reactive jet or torch for rapid ignition in the wave rotor. The traversing jet delivers hot gas with some active free radical species into a premixed ethylene-air mixture in a constant volume combustor from a continuous-flow prechamber torch igniter positioned at a fixed location adjacent to one end of the wave rotor with a substantial clearance gap. The finite-volume fluid dynamics and combustion simulation considers three channels of the wave rotor combustor, with combustion simulated fully in one channel, to optimize computational cost while closely mimicking the traversing jet motion and subsequent ignition and combustion processes using transient Reynolds Averaged Navier-Stokes (RANS) turbulence two-equation eddy-viscosity model with detailed chemistry mechanism with 81 species and 573 reactions. The simulation begins at a point in the wave rotor cycle when the channel has been filled and assumes a uniform mixture with substantial but variable residual turbulence. The pressure rise, flame travel, and heat release rates predicted are compared with experimental data previously collected from a highly instrumented wave rotor constant volume combustor rig. There are two significant aspects of the experimental wave rotor that could not be measured, but which may substantially affect its combustion processes: turbulent kinetic energy and turbulence scales of the mixture prior to ignition, and the level of active radicals in the traversing hot jet. The pre-chamber combustion model is manipulated to understand how dosing of free radical species enhances localized ignition initiation and accelerates overall fuel burn rate in the wave rotor channel. The turbulent kinetic energy in the channel was varied to understand the sensitivity of the combustion process to turbulence intensity and scales as the flame propagates along wave rotor channel away from the initial ignition jet zone. These findings significantly advance the understanding of a demonstrated wave rotor combustor with potential to revolutionize gas turbine engine technology.

Presenting Author: Rasheed K. Yinusa Purdue University in Indianapolis

Presenting Author Biography: Rasheed Yinusa is a PhD Student at Purdue University in Indianapolis. Rasheed completed his bachelor’s degree in mechanical engineering department at the Federal University of Technology Akure, Nigeria, graduating with a First Class Honors while also earning a place among the top 1% in the school of engineering. After his undergraduate studies, he moved to the United States and earned his master’s degree at the prestigious Howard University graduate school in Washingto DC, graduating with a 4.00 GPA. Since graduating at Howard, Rasheed has been working at Cummins – a global frontline leader in the diesel IC engine manufacturing industry. Rasheed currently leads On-Board diagnostics certification and compliance work at Cummins, while also enrolled for his PhD at Purdue University in Indianapolis. His research work focuses on the simulation of prechamber turbulent jet ignition and combustion in constant volume combustors and pressure-gain systems. Rasheed lives in Southeast Indianapolis with his wife and two kids.

Authors:

Rasheed K. Yinusa Purdue University in Indianapolis
Mohamed Razi Nalim Purdue University in Indianapolis