Fuse Magneto-rheological Fluid Extension Arming

With the development of structure design and the applications of hi-technology,the safety and reliability of the fuze was improved. Magneto-Rheological fluid (MRF)is a new kind of smart material. Under the high magnetic field, it can be transformedfrom Newton fluid into Visco-plastic solid instantaneously. This transformationrequires little power, short time and its working procedure can be controlled. MRF is apromising actuating medium in fuze delay arming device for its performancecharacteristic.A new kind of fuze delay arming device was designed according to thecharacteristic of the MRF based on the fluid delay arming device, in this dissertation.Theoretical analysis, numerical simulation and test verification were used toinvestigate. The main contributions of this dissertation include the followings:1. A state-of-the-art review on the updated progress of MR technology and fuzedelay arming devices, including the unique performance of MRF and the historyof safe-arming devices, was introduced firstly. A feasibility study of theapplication of MRF to fuze was explored. Then the main task of this dissertationwas summarized.2. Fluid dynamics model was presented using the theory of viscous fluid dynamicsand electromagnetics, combining constitutive equation and flow field with theinfluence of a magnetic field. A simplify mathematics model was set up and theimportant parameters which affect the leakage was discussed.3. The mathematics model of MRF-permanent magnetism magnetic field waspresented using the theory of magnetic route design. The important parameterswhich make MRF in solid state affecting the fuze safety at ordinary times waswork out by theoretical calculate. Ansoft software which based on finite elementwas used to analyze the magnetic field. According to the result of simulation, thetheoretical calculate of magnetic was confirmed.4. A kind of MRF delay arming device was designed and machininged using theparameters which work out by flow field analyse and magnetic field analyse,taking trajectory parameters of some fuze model into account.5. MRF delay arming device was investigated using the test rig we designed. Thegraphics of aperture-time was drawed. The aperture-time test curve tallies with thesimulation curve by compared with the result of the test and simulation, therefore,proved the correctness of the theoretical model. And the delay time of MRF device which based on trajectory parameters of some fuze model was fit fordemand.Finally, the work of this dissertation was concluded. The innovations andcontributions of this work were introduced. And also, the potential issues of thisresearch were pointed out. This dissertation deals with specific arm modelengineering practice and the theory will be tested by practice.