Simulation and optimization were applied to a capacitive sensor system based on electrical tomography technology. Sensors, consisting of Morgantown Energy Technology Center (METC) axial synchro driving guard electrode...Simulation and optimization were applied to a capacitive sensor system based on electrical tomography technology. Sensors, consisting of Morgantown Energy Technology Center (METC) axial synchro driving guard electrodes and two sets of detecting electrodes, make it possible to obtain simultaneously two groups of signals of the void fraction in oil-gas two-phase flow. The computational and experimental results showed that available sensors, charactered by high resolution and fast real-time response can be used for real-time liquid-gas two-phase flow pattern determination.展开更多
We consider the drift-diffusion (DD) model of one dimensional semiconductor devices, which is a system involving not only first derivative convection terms but also second derivative diffusion terms and a coupled Po...We consider the drift-diffusion (DD) model of one dimensional semiconductor devices, which is a system involving not only first derivative convection terms but also second derivative diffusion terms and a coupled Poisson potential equation. Optimal error estimates are obtained for both the semi-discrete and fully discrete local discontinuous Galerkin (LDG) schemes with smooth solutions. In the fully discrete scheme, we couple the implicit-explicit (IMEX) time discretization with the LDG spatial diseretization, in order to allow larger time steps and to save computational cost. The main technical difficulty in the analysis is to treat the inter-element jump terms which arise from the discontinuous nature of the numerical method and the nonlinearity and coupling of the models. A simulation is also performed to validate the analysis.展开更多
基金Project (No. 2002AA616050) supported by the Hi-Tech Researchand Development Program (863) of China
文摘Simulation and optimization were applied to a capacitive sensor system based on electrical tomography technology. Sensors, consisting of Morgantown Energy Technology Center (METC) axial synchro driving guard electrodes and two sets of detecting electrodes, make it possible to obtain simultaneously two groups of signals of the void fraction in oil-gas two-phase flow. The computational and experimental results showed that available sensors, charactered by high resolution and fast real-time response can be used for real-time liquid-gas two-phase flow pattern determination.
基金supported by National Natural Science Foundation of China(Grant No.11471194)Department of Energy of USA(Grant No.DE-FG02-08ER25863)National Science Foundation of USA(Grant No.DMS-1418750)
文摘We consider the drift-diffusion (DD) model of one dimensional semiconductor devices, which is a system involving not only first derivative convection terms but also second derivative diffusion terms and a coupled Poisson potential equation. Optimal error estimates are obtained for both the semi-discrete and fully discrete local discontinuous Galerkin (LDG) schemes with smooth solutions. In the fully discrete scheme, we couple the implicit-explicit (IMEX) time discretization with the LDG spatial diseretization, in order to allow larger time steps and to save computational cost. The main technical difficulty in the analysis is to treat the inter-element jump terms which arise from the discontinuous nature of the numerical method and the nonlinearity and coupling of the models. A simulation is also performed to validate the analysis.