Research on dynamic and static opening of metal diaphragmin double pulse solid rocket motor

In order to study the opening property of metal diaphragm in double pulse solid rocket motor, ductile damage model and brittle cracking model were used to simulate the dynamic and static opening process. The simulation static opening pressure was 3.46 MPa and the simulation dynamic opening pressure was 1.95 MPa. To further verify the accuracy of simulation, the verification tests were carried out. The real average static opening pressure was 3.75 MPa and the real average dynamic opening pressure was 2.2 MPa. The computational results agree with the tests results well. The numerical method in this article is effective. The static opening pressure is obviously higher than the dynamic opening pressure, which is considered to be due to the plastic deformation of the diaphragm, the material itself characteristics and stress relaxation of prefabricated defect. It can be found that opening mode of metal diaphragm is in line with expectations in the cold and heat tests, which can satisfy with the design requirements.