Factors Burning Rate Propellant Parametric Testing And Evaluation Methods And Their Impact

In order to accurately test and evaluate the characteristics of propellants burning rate, based on closed bomb combustion experiments, the burning rate parameters of propellants were studied by the methods of data-processing. The TEGN propellants was adopted as a typical example to systematic investigate the effects of structure, loading density, ignition intensity, test deviation et al. on the propellants burning rate parameters. Besides, effects of the burning rate and the inner-hole aspect ratios on erosive burning were investigated by closed bomb combustion and interrupted-burning tests of high-energy nitroamine. In addition, burning rate parameters versus the performance of interior ballistic was intensely analyzed by the classical interior ballistic models. The main conclusions as follows:The structure type and the size of propellants impressively affected the burning rate parameters. An increase of the inner holes of propellants leads to a booming of proportional burning rate coefficient u1, along with a decrease of burning rate pressure exponent n, and a extension in the exponential burning rate coefficient A. While the increase in the inner-hole aspect ratio results in a increase in the proportional burning rate coefficient u1, a decrease in the burning rate pressure exponent n, and a increase in the exponential burning rate coefficient A, respectively. The loading density of propellants was found to play a certain role in their experimental burning rate parameters, but there is no obvious trend between them when the loading density is in range of0.12g·cm-3～0.20g·cm-3. It is seen that the usage variance of igniting powder has little influence on the experimental burning rate parameters of the tested propellants. It is also seen that the pressure test deviation has a significant influence on the experimental burning rate parameters of the tested propellants.The inner-hole aspect ratios and the burning rate characteristics of the propellants have a great impact on their erosive burning. An increase in the inner-hole aspect ratio of propellants worsens the phenomena of erosive combustion, thus significantly affecting the results of burning rate parameters. A higher burning rate of propellant generatred a more significant impact the erosive combustion on burning rate parameters and a sharp increase of the proportional burning rate coefficient u1.Propellants burning rate parameters have significant influence on their ballistic performance. The deviation in the burning rate parameters of different propellant structure, might lead to the artillery maximum pressure changing more than60%. Therefore, standardized experimental conditions and advisable data-processing methods for evaluating the burning rate parameters of propellants will shaply favor an accurate result of burning rate characteristic.