三相电压型逆变器仿真的研究

本文首先通过对三相电压型逆变器数学模型的推导。然后在ＭＡＴＬＡＢ仿真软件环境下实现三相电压型逆变器数学模型,最后通过仿真实验验证。     

混凝土三相结构与性能研究

对混凝土的性能起决定作用的因素是其内部微观结构,传统观点认为混凝土是由骨料和水泥浆体组成的二相结构,现提出了混凝土微观结构的三相模型,即混凝土有骨料、水泥浆体和过渡带3个组成部分。并分析了混凝土微观结构的3个组成部分对混凝土强度、尺寸稳定性、耐久性能的影响,指出了混凝土的过渡带结构是影响其性能的关键因素。     

Two-Phase and Three-Phase Modeling of an Industrial Fluidized Bed for Maximizing Iso-Paraffins

The maximizing iso-paraffins (MIP) process is a new fluid catalytic cracking route to produce cleaner gasoline. Its major innovation is the diameter-transformed fluidized bed reactor which can be flexibly regulated to multiple distinct reaction zones. This study aims to accurately reveal complex behaviors in MIP reactor by two-phase modeling and three-phase modeling to extend its application. Both simulations of an industrial MIP reactor are compared in terms of solids and liquid concentration, temperature, coke content, gas velocity, and product yield. It is found the two-phase case is enough for predicting the region far away from the oil feedstock injection, and the other is the better choice especially in the first zone if the heat transfer model can be reasonably built.