The application of pressure cure molding technology can effectively reduce the structural integrity problems of casting solid rocket motors. In order to describe the curing and cooling process under this new technology more realistically, it is decomposed into two processes, pressurization curing, and pressure relief cooling and a time‐varying segmented solid propellant intrinsic equation applicable to the pressure cure molding technology is proposed. The constitutive equation takes into account the change in material properties caused by the change in the state of the propellant during the curing process. In order to accurately model the changes in mechanical properties of the propellant during curing, the present constitutive equations for this process are rewritten in incremental form and implemented in the user subroutine UMAT of the finite element analysis platform ABAQUS. The detailed derivation steps of the constitutive equation are introduced in this paper, and the subsequent application analysis is carried out with reference to the star‐shaped grain. The final stress and strain state of the propellant after cooling is used as the main analytical index. The results show that the pressure cure molding technology can effectively reduce the residual stress and the residual strain on the inner surface of the propellant grain. The pressure cure effect on the outer surface of the grain is relatively small compared to the overall reduction. The time‐varying constitutive model provides technical support for a more accurate description of the pressure cure process.
At present, the casting of large-size motors often adopts pressure cure. This technology can effectively reduce the risk of damage to the structural integrity of the grain in the case-bonded casting solid rocket motor. In this paper, ABAQUS is used to establish a finite element model of star-shaped grains. The whole process of pressure cure was simulated and modeled, and the Python script was redeveloped. The Evol evolutionary algorithm was used in ISIGHT to optimize the load parameters such as pressure value, attenuation coefficient of the relief curve, and the attenuation coefficient of the cooling curve. The effects of different pressure values and different cooling and depressurizing rates on the residual stress and strain were analyzed. The optimization results show that the closer the pressure value is to the theoretical pressure, the more significant the effect of pressure cure. However, the effect of stress and strain reduction in different directions is slightly different. The different cooling and pressure relief rates have a great influence on the process quantity. Pressure cure works best when the pressure attenuation coefficient is equal to 6850, and the temperature attenuation coefficient is equal to 8650. The optimization analysis of pressure curing provides a reference for engineering practice.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.