Benjamin Gutman

Impinging jets are commonly used to atomize propellants in liquid rocket engines. The specific link between the impinging jet sheet dynamics and the drop size and velocity pdfs is currently unknown. This study aims to fill in the gaps. Two experimental techniques were applied to the impinging jet atomization process, partial coherence interferometry (PCI) and digital inline holography (DIH). PCI was applied to measure dynamic sheet thickness while DIH was applied to determine fragment size-velocity pdfs for fragments that were axial ligaments, bow ligaments, and drops. Size and velocity pdfs for all three were obtained at several jet Reynolds (Re) and Weber (We) numbers. Results were interpreted in terms of dominant physical mechanisms evidenced in the time-resolved, three-dimensional, three-component holographic images.

Alex Friedman

The more than 100 million debris objects greater than 1 mm in space have become a great concern for safety of humans and assets in Earth orbit. The complexities and challenges of orbital debris orbit determination can be attributed to initial state uncertainties, errors in measurements, and limited observation time. The amount of information from each observation is time dependent; therefore, this research investigates how to determine when information from optical observations is maximized using observability analysis. Singular values of the observability gramian can be used to measure the amount of information known about the orbit. By looking at these values for an entire orbit, the optimal spacing between observations for maximizing information can be identified. For a perfect geosynchronous orbit object, three observations spread out by one-third of a day would result in an observable system with the maximum information. However, uncertainties and errors in the system will change this optimal spacing of observations. Discrete-time numerical observability analysis with measurement noise is implemented for a particle cloud representing initial state uncertainties. Knowledge of the optimal time to observe orbital debris will improve sensor tasking and orbit determination accuracy, thus reducing risks to humans and assets in Earth orbit.

What is the Research Symposium Series?

The Research Symposium Series is a department-sponsored forum for graduate students and advanced-level undergraduates to present their research to a general audience.

The Research Symposium Series is designed to: 

• Facilitate the exchange of ideas and knowledge among faculty and graduate students.
• Provide opportunities for students to develop their technical presentation skills.
• Promote the research activities of the department to undergraduates and other interested individuals.

2017 Prizes

• $500, $300, $200 for best three presentations
• $150 for best undergraduate presentation
• $150 for best abstract

Questions about the Research Symposium Series may be directed to:
aaerss@ecn.purdue.edu
https://engineering.purdue.edu/AAE/Academics/StudentOrgs/aaerss
*Winners in the presentation category cannot compete in that category the following year. The same applies for winners in the abstract category.