Nonlinear Effects in Instability of Solid-Propellant Rocket Motors

This paper is in two parts. The first section discusses briefly the various kinds of nonlinear effects associated with instability in solid-propell ant rockets and attempts to provide brief surveys of the ways in which various nonlinear phenomena may manifest themselves. The second section reviews and extends some of the work that has been carried out at the Applied Physics Laboratory on nonlinear instability phenomena arising from erosion. This work has been concerned with effects of erosion on stability and with the waveform of finite amplitude oscillations in motors with cylindrical propellant charges. In this connection, it is found that, especially for axial modes, significant waveform distortion may develop even for relatively small amplitudes of the pressure oscillation and that the wave shape tends to be a rather sensitive function of the time dependent response of the propellant.