On The Test Spectrum Of The Typical Missile Cabin Based On The Equivalence Of Acceleration Response For The Uniaxial And Triaxial Random Vibrations

The vibration environment test is an important part of the missile development work, which has a very important practical significance in ensuring the safety of the operating system, and the reliability of the electronic circuit, as well as the weak link in the design. In the traditional vibration environment test, the single axial vibration test method is used to approximate the true three-dimensional vibration environment of the equivalent products in three orthogonal axial vibration tests. Due to triaxial vibration test can be more realistically simulate the actual vibration environment, which gradually become the development trend of vibration environment test. Many public vibration test standards and specifications are formulated for traditional way of triaxial vibration test, and there is no authority at home and abroad of triaxial vibration test standard. If the uniaxial vibration test standard is directly used as the standard of the triaxial vibration test, it may cause damage to the mature product that has been passed in the uniaxial vibration test in the triaxial vibration test causing unnecessary over-design and other issues.In order to make consistent the uniaxial and the triaxial vibration test, triaxial acceleration responses on critical points are consistent with uniaxial vibration is required in the paper. This thesis aims to provide reference for triaxial random vibration test standards, carrying out the research on triaxial random vibration test spectrum based on the existing uniaxial random vibration test spectrum. The main research achievements are as follows:1. The reasons why structure dynamic response exist differences between the uniaxial and triaxial random vibration theoretically are studied. With the Ansys Workbench software, the difference of equivalent stress and acceleration response under the two different conditions are analyzed and compared, so that to acquaint the different effects of uniaxial and triaxial random vibration test.2. Research on response control algorithm of triaxial random vibration is carried out based on response control algorithm of uniaxial random vibration, which is studied based on the relationship between excitation and response in random vibration. The forward feasibility verification of the algorithm as well as the simulation of the random vibration test of uniaxial and triaxial is made with the help of Ansys Workbench software.3. The repairing and simplifying of the CAD/CAE model of typical cabin structure are studied, then meshing and contact setting of the model is carried out, finite element model.of the cabin structure is made. Modal analysis and random vibration analysis are conducted respectively on with fixture cabin model and without fixture cabin model, and the influence of the fixture on the system vibration characteristics is studied. Combined with uniaxial and triaxial random vibration response control algorithm, the load reverse of cabin with fixture on the uniaxial and triaxial random vibration is carried out.4. Simulation of the uniaxial and triaxial random vibration test on the cabin with the fixture is studied, and the differences of the structure dynamic responses under uniaxial and triaxial random vibration are comparated. In order to keep triaxial acceleration responses on critical points are consistent with uniaxial vibration at the same time, the research on equivalent cut program of triaxial random vibration test spectrum based on the existing uniaxial random vibration test spectrum is carried out, which experienced forward simulation verification.