Vivanco, Jose E (2014-12). A New Shock-Tube Facility for the Study of High-Temperature Chemical Kinetics. Master's Thesis.
A new stainless steel shock-tube facility designed for the study of chemical kinetics at elevated temperatures and pressures is described. It consists of a single-pulse shock tube capable of using both lexan diaphragms and die-scored aluminum disks of up to 4 mm thickness, and it has a relatively large driven-section inner diameter of 16.2 cm to minimize non-ideal boundary layer effects. Test times around 3 milliseconds are achievable at conditions ranging from temperatures between 600 and 4000 K and pressures between 1 and 100 atm behind the reflected shock wave. The facility includes a high-vacuum system capable of achieving ultimate pressures on the order of 1x10^-6 torr, a new gas-delivery system, a shock velocity-measurement scheme, a computer-based data acquisition system, and the option of implementing several optical diagnostics such as absorption and emission spectroscopy. The characterization of the shock tube, which includes pressure behavior, turnaround times and vacuum integrity, are presented. The uncertainty of the experimental temperature behind the reflected shock wave was found to be at most 10 K based on the shock velocity measurement technique used. A validation study for the facility was performed using methane-air as well as fuel-O2 mixtures highly diluted in argon. Additionally, a set of data on the ignition delay times of diluted acetylene-air mixtures is presented.