The document summarizes research on simulating hydrogen dispersion using the ADVENTURE_sFlow solver. It describes modeling hydrogen dispersion as an analogy to thermal convection problems. Two models are analyzed: a hallway model and a car garage model. The hallway model analyzes hydrogen dispersion from inlet, door, and roof vents in an empty volume. The car garage model analyzes hydrogen leakage from a fuel cell car in a full-scale garage. The objective is to demonstrate the feasibility of using the ADVENTURE_sFlow solver, which uses a hierarchical domain decomposition method, to efficiently solve large-scale problems like hydrogen dispersion in engineering facilities.
Stationary Incompressible Viscous Flow Analysis by a Domain Decomposition MethodADVENTURE Project
This document describes an iterative domain decomposition method for analyzing large-scale stationary incompressible viscous flow problems using finite element analysis. The method decomposes the domain into subdomains and solves the inner degrees of freedom using a skyline solver. Interface degrees of freedom are solved using preconditioned BiCGSTAB or GPBiCG iterative solvers. Numerical examples are provided to demonstrate the method on problems with over 1 million degrees of freedom and compare results to a monolithic finite element method solver.
The document summarizes research on simulating hydrogen dispersion using the ADVENTURE_sFlow solver. It describes modeling hydrogen dispersion as an analogy to thermal convection problems. Two models are analyzed: a hallway model and a car garage model. The hallway model analyzes hydrogen dispersion from inlet, door, and roof vents in an empty volume. The car garage model analyzes hydrogen leakage from a fuel cell car in a full-scale garage. The objective is to demonstrate the feasibility of using the ADVENTURE_sFlow solver, which uses a hierarchical domain decomposition method, to efficiently solve large-scale problems like hydrogen dispersion in engineering facilities.
Stationary Incompressible Viscous Flow Analysis by a Domain Decomposition MethodADVENTURE Project
This document describes an iterative domain decomposition method for analyzing large-scale stationary incompressible viscous flow problems using finite element analysis. The method decomposes the domain into subdomains and solves the inner degrees of freedom using a skyline solver. Interface degrees of freedom are solved using preconditioned BiCGSTAB or GPBiCG iterative solvers. Numerical examples are provided to demonstrate the method on problems with over 1 million degrees of freedom and compare results to a monolithic finite element method solver.
29. 第4回ADVENTURE定期セミナー ADVENTURE_Solidの関数
CG法に基づく領域分割法アルゴリズム
fKu =
gSuB =
線形化問題
( ) ( ) ( )
( ) ( ) ( )
( ) ( ) ( ) ( ) ( ) ( ) ( )
( )
( )
( )
( )
( ) ( )
=
∑∑ ==
N
i
i
B
i
B
N
I
I
B
N
I
I
N
i
Ti
B
i
BB
i
B
TN
IB
N
B
T
IBB
TN
B
N
IB
N
II
T
BIBII
fR
f
f
u
u
u
RKRKRKR
RKK
RKK
1
1
1
1
11
111
0
0
00
M
M
M
M
LL
LL
MMOM
MMO
L領域分割し,
Interface自由度
と各Subdomain
内部自由度に
整理
( ) ( ) ( ) ( )
( ) ( )
{ } ( ) ( ) ( ) ( ) ( )
( ) ( )
{ }∑∑ =
−
=
−
−=⋅
−
N
i
i
I
i
II
Ti
IB
i
B
i
BB
N
i
Ti
B
i
IB
i
II
Ti
IB
i
BB
i
B fKKfRuRKKKKR
1
1
1
1
Interface自由度に関する式に整理
このInterface自由度に関する問題を
前処理付き共役勾配法で解く
S: シュアコンプリメント行列
別紙1: pp.1-4を参照
31. 第4回ADVENTURE定期セミナー ADVENTURE_Solidの関数
シュアコンプリメント行列との
ベクトル積を計算する方法
( ) ( ) ( ) ( ) ( )
( ) ( )
pRKKKKRSp
N
i
Ti
B
i
IB
i
II
Ti
IB
i
BB
i
B∑ =
−
−= 1
1
( )
( )
( )
1
1
0
0
−
−
=
iI
K
K
i
IIi
ΓΓΓΓ
|
この部分をSubdomain毎に計算し,重ね合わせる
( )
( ) ( )
( ) ( )
= i
BB
Ti
IB
i
IB
i
IIi
KK
KK
K ローカル剛性行列
与えられたDirichlet境界に加えてInterface
境界も拘束したK(i)をLDLT分解したもの
用意するもの
32. 第4回ADVENTURE定期セミナー ADVENTURE_Solidの関数
シュアコンプリメント行列との
ベクトル積を計算する方法
• 考え方: Interface境界にuB
(i)=p(i)の変位拘束条件を与え,
Interface境界上の反力を計算する
( ) ( ) ( )
( ) ( ) ( )
−
=
pRKK
KKf
Ti
B
i
BB
Ti
IB
i
IB
i
II
i
I
0
0
~
( ) ( )
( )
( )
=
−
00
0
0
1
i
I
i
II
i
I f
I
Ku
i
~~
ΓΓΓΓ
( )
( ) ( )
( ) ( )
( )
( )
=
⋅
pR
u
KK
KK
q Ti
B
i
I
i
BB
Ti
IB
i
IB
i
II
i
~
1. K(i)を用いて変位拘束境界条件による右辺項を計算
2. K(i)-1を用いてSubdomain内部の変位量を計算
3. K(i)を用いてInterface上の反力量を計算
( ) ( ) ( )
pRKf
Ti
B
i
IB
i
I −=
~
( ) ( ) ( )
( ) ( ) ( )
pRKK
fKu
Ti
B
i
IB
i
II
i
I
i
II
i
I
1
1
−
−
−=
=
~~
( ) ( ) ( ) ( ) ( )
( ) ( ) ( ) ( ) ( ) ( )
( ) ( ) ( ) ( )
( ) ( )
pRKKKK
pRKpRKKK
pRKuKq
Ti
B
i
IB
i
II
Ti
IB
i
BB
Ti
B
i
BB
Ti
B
i
IB
i
II
Ti
IB
Ti
B
i
BB
i
I
Ti
IB
i
1
1
−
−
−=
+−=
+= ~
別紙1: p.7を参照