Event Detail
MECHANICAL ENGINEERING MS THESIS DEFENSE BY BÜŞRA KAHRAMAN
Title: Material Performance Determination for Nozzle Erosion in Hybrid Rocket Motors
Speaker: Büşra Kahraman
Time: January 10, 2023; 09:30
Thesis Committee Members:
Assoc. Prof. Mustafa Arif KARABEYOĞLU (Advisor, Koç University)
Prof. Dr. Metin MURADOĞLU (Koç University)
Prof. Dr. Tahsin Çağrı ŞİŞMAN (University of Turkish Aeronautical Association)
Prof. Dr. Onur TUNÇER (Istanbul Technical University)
Abstract:
Performance parameters such as thrust coefficient (CF) and specific impulse (Isp) are critical for rocket motor design. Reduction in the nozzle throat area causes a change in CF, thrust, and Isp. Nozzle erosion in hybrid rocket motors is a prominent factor that should be studied since hybrid rocket motors are still developing. This study investigates the erosion rates of different materials at various O/F ratios, equivalence ratios, and chamber pressures. Moreover, effects of the throat length on erosion were investigated as well. Performances of different graphite grades, metals, composites, and silicon carbide as nozzle materials were determined. Silicon carbide sintering procedure and the use of silicon carbide in hybrid rocket motors as nozzle material is one of the most important parts of this study due to being a research topic all by itself. There are only a few research about the use of SiC nozzles in HRM nozzles. Static firing test results are given, and erosion rates of nozzle throats are measured for each test. Nozzle throat diameters are measured before and after the tests by using both callipers and image processing toolbox in MATLAB®. Results show that the material selection and reduced O/F ratios are the most important factors for lower erosion rates.