分类： 物理学 >> 核物理学 提交时间： 2023-09-04
Li, Yunxiang
Meng, Lu
Huang, Zinan
Li, Song
Wang, Disi
Liu, Bo
Zhang, Youpeng
Peng, Tianji
Zhang, Lu
Su, Xingkang
Jiang, Wei
摘要： Steam generator tube rupture (SGTR) accident is an important scenario needed to be considered in the safety analysis of lead-based fast reactors. When the steam generator tube breaks close to the main pump, water vapor will enter the reactor core, resulting in a two-phase flow of heavy liquid metal and water vapor in fuel assemblies. The thermal-hydraulic problems caused by the SGTR accident may seriously threaten reactor cores safety performance. In this paper, the open source CFD calculation software OpenFOAM was used to encapsulate the improved Euler method into the self-developed solver LBEsteamEulerFoam. By changing different heating boundary conditions and inlet coolant types, the two-phase flow in the fuel assembly with different inlet gas content was simulated under various accident conditions. The calculation results show that the water vapor may accumulate in edge and corner channels. With the increase of inlet water vapor content, outlet coolant velocity increases gradually. When the inlet water vapor content is more than 15%, the outlet coolant temperature rises sharply with strong temperature fluctuation. When the inlet water vapor content is in the range of 5% to 20%, the upper part of the fuel assembly will gradually accumulate to form large bubbles. Compared with the VOF method, Euler method has higher computational efficiency. However, Euler method may cause an underestimation of the void fraction, so it still needs to be calibrated with future experimental data of the two-phase flow in fuel assembly.
分类： 数学 >> 数学（综合） 提交时间： 2018-09-22
摘要： In this paper, we prove several regularity results for the heterogeneous, two-phase free boundary problems $\mathcal {J}_{\gamma}(u)=\int_{\Omega}\big(f(x,\nabla
u)+(\lambda_{+}(u^{+})^{\gamma}+\lambda_{-}(u^{-})^{\gamma})+gu\big)\text{d}x\rightarrow \text{min}$
under non-standard growth conditions. Included in such problems are
heterogeneous jets and cavities of Prandtl-Batchelor type with
$\gamma=0$, chemical reaction problems with $0 2$ for $p-$Laplace equations, but
also in the singular
case of $1
分类： 矿山工程技术 >> 矿山工程技术其他学科 提交时间： 2024-07-08
摘要： Simulation of subsurface energy system involves multi-physical processes such as thermal, hydraulical, andmechanical (THM) processes, and requires a so-called THM coupled modeling approach. THM coupled modelingis commonly performed in geothermal energy production. However, for hydrocarbon extraction, we need toconsider multiphase flow additionally. In this paper, we describe a three-dimensional numerical model of non-isothermal two-phase flow in the deformable porous medium by integrating governing equations of two-phasemixture in the porous media flow in the reservoir. To account for inter-woven impacts in subsurface condi-tions, we introduced a temperature-dependent fluid viscosity and a fluid density along with a strain-dependentreservoir permeability. Subsequently, we performed numerical experiments of a ten-year water flooding pro-cess employing the open-source parallelized code, OpenGeoSys. We considered different well patterns with colderwater injection in realistic scenarios. Our results demonstrate that our model can simulate complex interactions oftemperature, pore pressure, subsurface stress and water saturation simultaneously to evaluate the recovery per-formance. High temperature can promote fluid flow while cold water injection under non-isothermal conditionscauses the normal stress reduction by significant thermal stress. Under different well patterns the displacementefficiency will be changed by the relative location between injection and production wells. This finding hasprovided the important reference for fluid flow and induced stress evolution during hydrocarbon exploitationunder the environment of large reservoir depth and high temperature.
点击量
通过
点击量
下载量
评论
待评议
