国际会议演讲稿.doc

1. IntroductionGood afternoon, Ladies and gentlemen.I am honored to have been invited to speak at this conference. I am a PhD student from XXX and currently doing some research on Instrument Science and Technology.Today, my topic is Conceptual Design of an Evaluation Device for Power Test of Explosives.The content of this presentation is divided into 4 parts: in section 1, I will introduce the Research Status Quo of some existing methods for power test at Home and Abroad; in section 2, I will give the overall design and testing principle of the device; the mathematical model and simulation results will be showed in section 3; and finally, I will make a conclusion.Before entering the theme,lets look at what is the power of explosives.The sum of mechanical work to surrounding medium by explosion is called power of explosives, which reflects the ability of the expanding gas produced by explosion and is also an important indicator for evaluating the performance of explosives.2. BodySection 1:Research Status Quo at Home and AbroadThese are some existing methods for power test of explosives：1) lead-cast method 2)blasting funnel method 3)ballistic mortar method 4)underwater explosion method 5)ballistic projectile methodLets look at the advantages and disadvantages of two typical methods for power test.The lead-cast method is the first standard method in the world.It is easy to operate and does not require specialized test equipment.However,the little test quantity of explosives,the physical properties as well as different manufacturing processes of lead-cast result in a larger experimental error.In addition,the lead-cast is disposable and high cost,therefore the international community adopts the underwater explosion method as well.This method can not only test large quantity of explosives,but also has a good reproducibility of experimental data.However,the test system of underwater explosion requires large initial investment,complex experiment,high test cost and professional testers.Therefore, it is necessary to establish a simple, reliable and accurate power test method.The simple and practical evaluation device introduced in this presentation can realize the accurate and reliable measurement on power test of explosives.Section 2:Design of Device for Power Test of ExplosivesHere you can see a figure which shows the schematic of the overall design scheme.This device can be divided into three components.This part(爆炸腔) is used to store and detonate explosives;This part（驻退机、复进机）can consume the energy generated by explosion;The other part(连接和承载组件) is connection andsupport component.The figure 2.2 shows the function of various components.Based onthe above analysis,the total energy generated by explosion can be divided into the following energy:Hydraulic energy of recoil mechanism,Gas energy of counter-recoil mechanism,Energy of the remnant explosion gas,Friction heat and Other micro energy.Section 3:Mathematical Model and Simulation ResultsThe Mathematical Model of Device is based on two Basic Principles: 1)Thermodynamic Equation of Gas State ; 2)Newtons Second Laws of Motion.Through a series of deduction,acomprehensiveequation of the device is obtained.This is its initial condition.We can getthe value of each parameter by solving the equation.The figure 3.1 shows the change of pressure at the just moment of explosion.It is the simulation results under the condition of 76.8ggram of TNT.Then solve theequation through computer,I get The Curve of Pressure and Motion.From these curves, we can draw the following conclusions:The pressure value in the explosion chamber decreases rapidly at first. Then it decreases slowly and tends to be stable in the end. The acceleration is very large at first and then decreases rapidly. It does not increase until the value reduces to negative. The acceleration tends to 0 in the end. The velocity increases rapidly at first, then reaches the maximum value. After this, it decreases slowly and tends to 0 finally. The displacement increases rapidly at first, then increases slowly and stabilizes at around 0.5m .The curves obtained from the comprehensive equation fit well with the expected results and the energy can be estimated by the curves. It is proved that the test principle of the device is feasible. The equation established and parameters selected are reasonable.Section 4:ConclusionsTo sum up,the evaluation device for power test of explosives is designed based on the principle of conservation of energy. It has the advantages of simple operation, high test precision, good repeatability and can be operated indoors. The device can provide an effective evaluation method for power test of explosives and has the guiding significance for improving test precision of power test of explosives.Thats all. Thank you! Are there any questions