Optical prechamber-equipped high-pressure large-bore optical combustor for fundamental combustion studies.

Abstract

An optically accessible prechamber-equipped constant volume combustion chamber (CVCC) has been designed and installed at the University of Minnesota to investigate turbulent jet ignition and reacting flows. The CVCC features an optically accessible windowed prechamber, allowing the extensive study of the combustion physics inside the prechamber. The prechamber is also modular, allowing multiple internal geometries and nozzle configurations. Two pairs of optical windows in the main combustion chamber, along with a bottom window axisymmetrically viewing the prechamber nozzle, provide exceptional optical accessibility. Optical techniques such as schlieren imaging and chemiluminescence, along with laser diagnostics, can be employed to gain a fundamental understanding of turbulent jet ignition chemistry. The CVCC is designed to withstand a maximum combustion pressure of 100 bars. Multiple standardized and custom ports on the main chamber allow various fueling techniques and sensor integration. The performance and reliability of the CVCC were demonstrated through prechamber and main chamber visualization studies of nanosecond spark-assisted turbulent jet ignition. The optically accessible prechamber-CVCC setup, therefore, provides a platform for highly detailed combustion analysis.