Study of a new kind of multipulse rocket motor

A new method for multi-ignitable rocket motor design has been proposed in t his paper, by analyzing Row, heat-transfer, and combustion of a non-Newtoni an pasty propellant, in which oxidizer and fuel binder are mixed homogeneou sly. The new motor has advantages found in both solid- and liquid-propellan t rochet motors. The motor discussed in this paper is also thrust adjustabl e, Moreover, because the propellant is ignited by surplus heat from the com bustion chamber no additional ignition energy is needed. The key technology of this new method is the proposed reignitable igniter. A two-dimensional flow and heat-transfer model of the propellant inside the reignitable ignit er has been developed. Control equations have also been solved numerically. Propellant temperatures inside the igniter holes have been obtained, in co njunction with a simple ignition criterion. The relationship between ignite r temperatures, igniter length, igniter diameter, and drive pressure has al so obtained. A combustion model applicable to the new pasty propellant is p roposed on the basis of the current solid-propellant BDP (Beckstead-Derr-Pr ice) combustion model. A prototype test apparatus has also been built for m ultipulse firing. Seven operation pulses were obtained. Each pulse lasts ab out 5 s, and the time interval between pulses is approximately 2 s.