The reporter learned from the first Academy of China Aerospace Science and Technology Group on the 28th that the 702 institutes affiliated to the Academy recently successfully completed the parallel static and dynamic joint test of China’s new generation manned launch vehicle, which strongly supported the smooth transition of the development of this type of rocket to the initial sample development stage.
This test is an important test to verify the key technology of the new generation manned launch vehicle with multiple parallel machines and force transmission at the bottom of the box. It is a landmark work for the model to enter the preliminary sample development stage. Wang Xiaohui, director of the 702 Institute, said that the successful completion of the test marks China’s first breakthrough in the large load static and dynamic joint test technology, which is an important innovation in test methods and test capabilities, and has laid a solid foundation for the new generation of manned launch vehicles to adopt the parallel technology of multiple high thrust engines.
“This is the largest scale, the most difficult technology and the most complex test process carried out so far in the field of mechanical testing in China.” Zhu Xiquan, deputy chief designer of 702 Institute, introduced that the test needs to break through the joint loading of static thrust and vibration load of multiple engines under actual flight conditions, involving key test technologies such as vibration elastic boundary simulation, static load elastic loading of nearly 1000 tons, and multi machine joint multi-dimensional vibration control and loading under large static load.
The diameter of the basic stage module of the new generation manned launch vehicle is 5 meters, and multiple 120 ton engines are installed. Zhu Xiquan said that the multi machine parallel technology of high thrust engine is the first time that China’s launch vehicle has adopted, which has brought about the coupling of static and dynamic forces of complex structures and the nonlinear transmission problem under the action of joint loads. It is one of the key technologies that the new generation of manned launch vehicles need to deepen research. In order to analyze and solve this problem and verify the effectiveness of the design scheme, the technical team designed and implemented the first multi machine parallel static and dynamic joint test in China.
Since 2019, 702 Institute has demonstrated and determined the test technical scheme with relevant units. According to the plan, the team has successively broken through the key technologies required for the test, and this year developed a static and dynamic load joint loading test system composed of 28 sets of 50 ton oil and gas support systems, multiple sets of 20 ton induction vibration tables and a set of 1000 ton vibration elastic boundary system.
Houjingfeng, the design director of the test system, introduced that four oil-gas support systems and an induction shaking table constitute a set of static and dynamic combined excitation system, which can simulate the excitation of an engine to the rocket structure. Multiple systems can simulate the excitation load of multiple engines on the rocket. The test system is complex and involves many subsystems. The team gathered intelligence to tackle key problems, iterated the scheme and subsystem principle design layer by layer, conquered a number of key technologies, and turned the complex technical scheme into an engineering reality.
In view of the difficulty of static and dynamic combined loading test technology, technicians carried out the research on the combination of virtual and real test method, and ensured the success of the test scheme through digital process simulation and virtual test. Bi Jingdan, the person in charge of the test, introduced that the digital process simulation technology effectively guided the virtual installation process of the test, and optimized, checked and verified the assembly and commissioning process of the test products and test system equipment.
In addition, there are unknown scientific mechanism problems in the combination of multiple segments, the bearing capacity of the structure under complex boundaries and environments, as well as the load transfer law and structural response. Yang Rong, the head of the test subsystem, introduced that the test team innovatively adopted the digital test verification idea of combining physical test and virtual test, modified the simulation calculation model with the measured test data, identified the weak links of the integrated structural design with the modified virtual model, obtained the load and environmental conditions of the real working conditions, and then verified the bearing capacity of the tail cabin structure through simulation, The force transmission and response laws of complex structures are evaluated. (promise reporter Fu Yifei)