非均匀管道中加压流动的动理学格式

加压管道焊接件稳态蠕变的摄动法分析

Steady-State Creep Analysis of Pressurized Pipe Weldments by Perturbation Method

采用摄动法对加压环向管道焊接件在稳态蠕变下的应力进行分析，通过将未摄动解视为均质管道应力场，并利用辅助线弹性问题定义修正项，简化了多材料组件的参数分析。

Unsteady mixed flows in non uniform closed water pipes: a Full Kinetic Appraoch

We recall the PFS model constructed for the modeling of unsteady mixed flows in closed water pipes where transition points between the free surface and pressurized flow are treated as a free boundary associated to a discontinuity of the gradient of pressure. Then we present a numerical kinetic scheme for the computations of unsteady mixed flows in closed water pipes. This kinetic method that we call FKA for "Full Kinetic Approach" is an easy and mathematically elegant way to deal with multiple transition points when the changes of state between free surface and pressurized flow occur. We use t…

封闭水管中非稳态压力流的动力学格式

A kinetic scheme for unsteady pressurised flows in closed water pipes

提出一种用于封闭水管中瞬态压力流计算的动力学数值格式，基于守恒双曲偏微分系统的动力学公式，并通过对均匀管道水锤问题的数值验证，与工业代码结果吻合良好。

A model for unsteady mixed flows in non uniform closed water pipes and a well-balanced finite volume scheme

We present the derivation of a new unidirectional model for We present the derivation of a new unidirectional model for unsteady mixed flows in non uniform closed water pipes. We introduce a local reference frame to take into account the local perturbation caused by the changes of section and slope. Then an asymptotic analysis is performed to obtain a model for free surface flows and another one for pressurized flows. By coupling these models through the transition points by the use of a common set of variables and a suitable pressure law, we obtain a simple formulation called PFS-model close …

A kinetic scheme for transient mixed flows in non uniform closed pipes: a global manner to upwind all the source terms

We present a numerical kinetic scheme for an unsteady mixed pressurised and free surface model. This model has a source term depending on both the space variable and the unknown, U, of the system. The source term is composed by a topography, a section variation, a curvature (also called corrective) and a friction term. Using the Finite Volume and Kinetic (FVK) framework, we propose an approximation of the source terms following the principle of interfacial upwind with a kinetic interpretation: the source term is not treated as a volumic term, but included in the numerical fluxes. Then, several…

The Vlasov-Navier-Stokes system in a 2D pipe: existence and stability of regular equilibria

In this paper, we study the Vlasov-Navier-Stokes system in a 2D pipe with partially absorbing boundary conditions. We show the existence of stationary states for this system near small Poiseuille flows for the fluid phase, for which the kinetic phase is not trivial. We prove the asymptotic stability of these states with respect to appropriately compactly supported perturbations. The analysis relies on geometric control conditions which help to avoid any concentration phenomenon for the kinetic phase.