Solid propellants oscillatory burning

Heterogeneous solid propellants possess additional mechanisms with potentials for producing oscillatory burning. For example, certain metalized composite propellants have been observed to burn in the laboratory with identifiable ranges of frequencies of oscillation [118] in this case, the mechanism may involve chemical interactions between the metal and the oxidizer. It was indicated in Section 9.1.5.5 that heterogeneities introduce at least local periodicities and that, in the presence of a mechanism for synchronizing the phases of the oscillations over the surface of the propellant, sustained coherent oscillations of the combustion will occur. A review is... 

A. G. Smith, A Theory of Oscillatory Burning of Solid Propellants Assuming a Constant Surface Temperature, in Solid Propellant Rocket Research, vol. 1 of Progress in Astronautics and Rocketry, M. Summerfield, ed.. New York Academic Press, 1960, 375-392. 

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