Study On The Propellant Ablation Properties Of Laser Sustained And Electromagnetic Thruster

Laser sustained and electromagnetic propel system is one of the most potential thrusters,which has the advantage of high ratio in propellant use and reliability.In this thesis,numerical analysis and experimental measure are used to explore the properties about the ablation of propellant.The mainly works as following:Computational formula of thermal conductivity about composite material was summarized,which is composed with Teflon and Al.At the same time.Steady state experimental method is put to measure the thermal conductivity of this material.By comparing the numerical value with the theoretical value,the pure connection in series is summarized to calculate the thermal conductivity of the composite material.Based on the Fourier's law of heat conduction,a continuous laser ablation three dimentional model about the propellant before and after meltdown has been established.The effective factors which are related to temperature of propellant have been found like the power of laser or the parameter of propellant.It is obvious that the temperature law in the laser focus area is as same as the laser model which correspond to Gaussian law.The temperature in laser focus area is higher than any other area and the rate of heat diffusion get faster with the rise of propellant temperature.The temperature become lower in the bigger thermal conductivity propellant at the same laser power.The microthermocouples and infrared thermometer are used to measuring the surface temperature of propellant.For the Teflon,it is hand to set fire in air with 10 w of laser power.However,laser can set fire to the composite materials at the power 2w and 1.5w with the temperature 812 Kand 708K.What's more,for the composite matericals,it is more active with more Al.At last,it can improve the function of a thruster by the improvment of matericals proportion.