Combustion Instabilities in a Simulated Liquid Combustion Chamber
Open Access
- Author:
- Kwolek, Megan Jo
- Area of Honors:
- Aerospace Engineering
- Degree:
- Bachelor of Science
- Document Type:
- Thesis
- Thesis Supervisors:
- Michael Matthew Micci, Thesis Supervisor
Dr. Mark David Maughmer, Thesis Honors Advisor
Dr. George A Lesieutre, Faculty Reader - Keywords:
- liquid rocket combustion chamber
magnetic flowmeter
acoustic admittance
response
combustion instabilities - Abstract:
- Combustion instabilities are critical to the performance of liquid rocket combustion engines. Combustion instabilities lead to high pressure and velocity fluctuations, which can cause damage to engine components and even lead to system failures. It is important to gain an understanding of these burning characteristics and be able to implement methods of avoiding these instabilities in the design of liquid rocket combustion chambers. This experiment measures the acoustic admittance and response function of a propellant combination during combustion. The sign of the real component of the response function indicates whether acoustic energy is added or subtracted from the chamber. By modulating the exit area with a geared tooth wheel, a pressure oscillation is induced. Velocity fluctuations are measured using a magnetic flowmeter, which implements the concepts of Faraday’s Law. The pressure and velocity fluctuations are measured at the same axial location. At high frequencies, realistic chamber conditions can be simulated and the acoustic admittance and response can be determined. The resulting measurements are then compared to existing data to evaluate the accuracy of the method. The future work to develop this method into a commercial application is also discussed.