摘要
基于空气中氡子体和气溶胶粒子的行为规律,研究了一种小体积氡室中氡子体状态参数稳定调控方法,即通过调节小体积氡室总换气率和气溶胶粒子数浓度实现氡及氡子体浓度、平衡因子和未结合态份额等状态参数稳定调控方法。建立了调控物理模型,根据模拟条件甄选氡子体和气溶胶粒子行为参数,采用Matlab模拟计算了小体积氡室氡子体状态参数的调控范围,并将模拟计算值与实验值进行比对,部分验证本文建立的调控方法。模拟计算结果表明,本研究所建立的调控方法可在小体积氡室内实现氡子体浓度、平衡因子和未结合态份额的稳定调控。本研究建立的调控方法为实验研究提供了初步的理论基础。
A control method of radon progeny state parameters in small radon chamber was established based on behavior theory of airborne radon progeny and aerosol particle.The state parameters including radon and radon progeny concentration,equilibrium factor and unattached fraction were controlled steadily in small radon chamber by adjusting the total ventilation rate of radon chamber and aerosol particle number concentration.Physical model of the control method was established,and the behavior parameters of radon progeny and aerosol particles were selected considering the simulation condition.The control range was calculated by Matlab program,and the physical model was partly verified by inter-comparing theoretical results and experimental data achieved by radon laboratory of University of South China.The inter-comparing results prove that the control method constructed in this paper is applicable,and the control methodprovides a preliminary theoretical foundation for the control experiment of radon progeny state parameters in small chamber.
引文
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