Performance prediction of nozzleless solid propellant rocket motors

Özer, Ali Can
Integral rocket ramjet (IRR) type propulsion systems have many advantages over conventional solid rocket motors when used in tactical missile systems. Nozzleless boosters are one of the applicable concept choices for the system [1]. During the design and development phase of solid propellant rocket motors, simulation and prediction of behavior of a given motor by numerical tools is important in terms of decreasing the development duration and costs. The present approach includes performance prediction of nozzleless solid propellant rocket motors. In order to predict performance and numerically simulate the flow field inside the motor, first internal ballistics of the motor is examined theoretically. Then, quasi one dimensional internal ballistics model is constructed and solved numerically through inside the motor. In order to predict burning rate, an erosive burning relation has been implemented into the numerical scheme. To verify the flow solver, results against the Sod shock tube problem is obtained. Grid resolution and time step size sensitivity study is made. The results of numerical internal ballistics simulations are compared with the experimental nozzleless motor firing results found in literature are simulated and compared. Simulations are conducted for both quasi steady and unsteady approach, and outcomes of two approaches are compared as well. Proposed numerical scheme is promising for predicting thrust and pressure histories of nozzleless solid propellant rocket motors. Also from the design point of view, parametric studies are conducted. Effect of grain geometry and propellant burning rate are studied.
Citation Formats
A. C. Özer, “Performance prediction of nozzleless solid propellant rocket motors,” M.S. - Master of Science, Middle East Technical University, 2015.