Study On Dynamic Stability Of High Storage Ratio Lightweight Membrane Structure

The unfolding dynamics analysis of the space inflatable expandable structure has attracted more and more attention from many researchers due to the development of space technology,and it has the advantages of light quality and small size compared with the traditional unfolded structure.However,it is difficult to simulate the space environment to carry out the ground test of the inflatable structure of the expandable structure.Therefore,finite element(FE)simulation has become an important research method.In order to increase the stability and reliability of the space structure during inflation,to achieve the smooth development of the space structure,and to accomplish its engineering objectives,this paper carried out the research work as follow:(1)The FE model of velcro and airbag was created.The velcro test and simulation results were compared,and the airbag inflation was simulated based on the control volume(CV)method to verify the reliability of the model.(2)Focus on the study of the important support structure of the pods in the space membrane rod structure,compare the two schemes for establishing the single rod inflation model,select the distribution modeling method,and simulate the three steps of flattening,crimping and aeration.The pods can be inflated smoothly and in an orderly manner.At the same time,the effects of different velcro bonding areas an d aerated mass flow on the inflation of the pods were studied.Matching the appropriate velcro area and inflation flow rate,the pod bar inflation vibration is minimal,which is in line with actual engineering requirements.(3)On the basis of the pod bar,the development process of the integral membrane rod structure is studied.In order to meet the needs of large-scale calculation and improve the calculation efficiency,parallel computing technology is used to simulate the simulation.Analyze the expansion process of the membrane rod structure and the internal pressure of the airbag under different inflation mass flow rates,and obtain various parameters that can stabilize the inflation and expansion of the membrane rod structure,and provide guidance for practical application.Based on the results of this paper,not only the problems of gas-solid coupling during the inflation process are explored theoretically,but also some guidance is provided for the structure type selection,including parameter setting and structure selection,and also the realization of the membrane rod structure.At the same time,the foundation is laid for the application of diaphragm rod structures in large space mechanisms.