| The microsphere（capsule）filled fuel gas is one of the core component of the target in the inertial confinement fusion experiment（ICF）.The content and change of the fuel gas or diagnostic gas in the microsphere are the focuses of ICF experiment.At present,the microspheres are filled mainly by microtubules,perforating and thermal diffusion methods.However,the volume of the microsphere so small（microliter）and the fill-tube in the microtube method is so thin（a few microns）,that It’s difficult for the experimental device to measure the accurate data of the pressure in the microsphere during the filling and evacuation processes.Therefore,it is particularly important to study the gas flow in the microtube and adopt an appropriate model to predict the change of the pressure in the microsphere.In order to solve the problem of difficult in sample injection,we used quadrupole mass spectrometry with customized crushing chamber to measure the gas content in the microspheres inflated by perforated and thermal diffusion methods.For the measurement of trace gas mass spectrometry,it is important to study the relationship between the calibration factor of mass spectrometry and the gas to be analyzed for improving the measurement accuracy.This paper is divided into three parts:（1）Two-component gas flow in microchannels:DS2V was used to simulate the case of two-component gas flow to determine its feasibility,and the concentration separation of He-Ar two-component gas with the He concentration of 0.5 at the entrance of microtubules in microtubules was studied.The results show that,with the pressure ratio between the inlet and outlet of microtubules increases,and the lowest point of He concentration in the tube gradually approaches the inlet of microtubules.The concentration of He at the outlet of the tube decreases with the increase of the length-diameter ratio.When the number of Kn at the inlet of microtubules increases from 0.01 to 5,the concentration of He at the outlet of microtubules decreases at first and then increases.（2）Based on the flow theory applicable to the whole range of Knudsen number,the theoretical model of microsphere filling and evacuation processes was established,and the reliability of the model was verified by experiments.The gas-filling process of a single tube microsphere and the gas flow processes of removing air in the microsphere by three different methods are studied The results show that the longer the tube length,the smaller the diameter,the higher the filling temperature and the longer the filling time in the process of constant pressure filling.In the process of microsphere evacuation,when the single pipe pumping method was adopted,the total time required to reach the standard was 1961.77h.In contrast,when filling three times and evacuation four times were adopted,the evacuation time could be controlled to about 67min.However,it only takes about 11 min when double-line flow washing method is used.（3）The trace gases with the same content range as that in the microsphere can be obtained,by the calibration chamber and vacuum tubes installed on the intake pipe of the mass spectrometer,The calibration factor of mass spectrometer was studied.The results show that the value of D2pressure calibration factor can be affected by Ar and can be expressed as a function of the total pressure of the deuterium-argon mixture and the deuterium-argon concentration,and can be used to improve the accuracy of measuring the pressure of each component in the deuterium-argon mixture. |
