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Two methods for processing the results of closed-bomb tests of propellants are proposed: a method for determining the force of propellant, the covolume of propellant gas, and the pressure dependence of the degree of propellant combustion that takes into account the heat exchange between the combustion products and the walls of the closed bomb; a procedure for determining the linear behavior of unsteady combustion in the form justified by Ya. B. Zel'dovich. It is shown that accounting for heat losses is necessary not only to determine the force of propellant and the covolume of propellant gas but also to determine the combustion behavior.Closed-bomb testing, i.e., combustion of propellant samples under constant volume conditions (in a closed bomb [1]) is virtually the only method for determining the calorific characteristics of propellants and identifying combustion and gasification behaviors. In such tests, only the time dependence of the combustion product pressure is usually recorded, from which the indicated characteristics are then established under a number of simplifying assumptions. Existing methods [1] for processing experimental data were developed primarily at the end of the 19th century and in the first third of the 20th century and were based on the pressure measurement techniques available at that time. Current measuring and recording instruments have considerably increased the accuracy of experimental information and opened new possibilities for the development of advanced methods of data processing.The present paper describes methods for determining the force of propellant, the covolume of propellant gas, and the unsteady effects of propellant combustion taking into account the heat exchange of combustion products with the walls of the bomb. It should be noted that because of the short time of the process and the small thickness of the heated layer (≈0.1 mm), direct measurement of the bomb-wall temperature or the heat fluxes from combustion products is a difficult problem which has not yet been solved. Therefore, in the development of the methods described in this paper, it was assumed that only the pressure-time dependence is known from experiments. This situation is typical of the majority of closed-bomb test facilities. The results presented here were obtained in experiments using T6000 piezoelectric pressure transducers, whose signal, after being amplified by the Neiva 2K strain station, was recorded by an ATSP 10-bit analog-to-digital converter at a frequency of 1 MHz.The pressure-time dependences obtained in the experiments were processed in two steps. In the first step, the force of propellant, the covolume of propellant gas, and the pressure dependence of the degree of burnout were determined with allowance for heat losses using an improved version of the method described in [2]. In the second step, the time dependence of the linear burning rate was found.In practice, the dependence p(t) is recorded starting with a certain pressure higher than atmospheric pressure p 0 (p 0 ∼ = 10 MPa); the ...

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