Dillier, Catherine Anne Marie (2016-12). Development and Characterization of a New Very High-Pressure Strand Burner for Studying Propellant Burning Rates at Extreme Temperatures. Master's Thesis.
For years, additives have been used to tailor solid propellant behavior for specific applications. The propellant is often exposed to harsh environments during combustion such as extreme temperatures and high pressures. While the burning rates of AP/HTPB-based solid rocket propellants up to pressures of 2000 psi are well documented, relatively little data at higher pressures exists. Therefore, a new high-pressure, constant-volume strand burner facility has been installed and characterized at Texas A&M University to test pressures up to 10,000 psi. The design is primarily based on the current test vessel, strand burner II or SB-II and includes a cylindrical main body, two endcaps, and a bolt which is used to hold the test specimen. In addition to high-pressure testing, the new strand burner will be used to determine the temperature sensitivity of AP/HTPB-based solid propellants at high and low temperatures. For low-temperature tests, the strand burner will be placed horizontally into a freezer and cooled to -65?F; whereas for the high-temperature tests, the strand burner will be heated to 194?F using resistance heating tape and mounted vertically. Two 80% monomodal AP/HTPB composite baseline propellant formulations were used to verify the new strand burner's design, one with an average AP particle size of 200 ?m and the other, 138 ?m. The resulting burning rates and temperature sensitivities were compared to historical data with good agreement, thus validating the new strand burner facility and experimental procedures. This thesis details the development and characterization of the new high-pressure strand burner.