Characterization of the pressure wave from a shock tube using numerical simulations

Research presented in this thesis stems from rising concern about blast-induced traumatic brain injury (TBI). It has been hypothesized that brain tissue is damaged by the blast wave generated during an explosion, but the mechanism of tissue injury is unknown. The pressure wave produced by a typical explosion includes a peak pressure, or overpressure, and positive and negative pressure phases; each component of this blast wave may make a unique contribution to injury. A simple device called a shock tube is capable of generating the characteristics associated with the blast wave. This thesis presents a computational model of a shock tube being used in our laboratory to investigate the above-mentioned characteristics of the blast wave. The shock tube is approximately 135 cm long and has a 2.54 cm inner diameter. This research has two primary objectives. The first is to characterize blast wave properties as a function of shock tube independent parameters. In our shock tube, the independent parameters are driver section length and initial pressure. Because the purpose of this research is to study injury due to pressure wave loading alone, the target is placed outside the tube to avoid interaction with venting gases. Quantifying the appropriate region for testing is the second main objective of this research.