Publication Date


Document Type


Committee Members

Mark Gruber (Committee Member), James Menart (Committee Member), J. Mitch Wolff (Advisor)

Degree Name

Master of Science in Engineering (MSEgr)


A pressure-based investigation was conducted on a gaseous fueled axisymmetric scramjet flowpath in Research Cell 22 located at Wright Patterson AFB. The investigation followed the work performed by Waltrup and Billig using combustion data to validate the form of the correlation in an attempt to achieve a good predictive tool for isolator length. Two years of axial wall pressure data using Mach values of 1.8 and 2.2 were analyzed in this investigation. The combustion data was shown to follow the same quadratic distribution show in Waltrup and Billig's work with the data being shifted to the right relative to the correlation implying that the original correlation would have under predicted the length of the isolator. The data was then curve fitted to be able to generate new coefficients while maintaining the form of the quadratic equation developed by Waltrup and Billig resulting in a new equation that was in good agreement with the compiled data where the first order coefficient has a value of ~247 and the second order term a value of ~149. The conclusion being that the shock train length is independent of the process or mechanism used to backpressure the duct but significantly sensitive to the axial area distribution.

Page Count


Department or Program

Department of Mechanical and Materials Engineering

Year Degree Awarded


Creative Commons License

Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License.