Page 89 - 《真空与低温》2026年第2期
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208 真空与低温 第 32 卷 第 2 期
[ (m) ]
∂ [ (B) (m) (m) ] ∑ (B) (m) (m) (m) ∂H δ ∂T (m)
(1−ϕ )(1−ϕ )ρ s C v,s T + (1−ϕ )ϕ γ ρ =
∂t δ ∂T (m) ∂t
δ=o-H 2 ,p-H 2
∑ [ ] ∑ [ ] [ ]
(B) (m→B)
− H q (m→B) + H q +h mB a mB T (B) −T (m) +S e ±S r H (m) (15)
δ δ δ δ δ
δ=o-H 2 ,p-H 2 δ=o-H 2 ,p-H 2
1.2.2 模型的数值求解 表物理量的时间坐标,下标(i,j)、(f,j)、(i,k)等代
本节采用控制容积积分法对数值求解模型 表物理量的空间坐标。
进行离散,为了描述的简洁性我们采用二维网格 将方程式(12)~(15)进行隐式离散,得到方程
对计算区域进行划分,并取区域中空间坐标为 式(16)~(19)。
(i,j)的节点进行研究。后续式中划分的空间网格 将方程式(1)、(3)进行显式离散,得到方程式
步长为 ∆x和 ∆y,时间步长为 ∆t。上标 n 和 n+1 代 (20)和式(21)。
[ ] ∑ [ ] ∑ [ ]
( ) n+1 ( ) n ( ) n+1 ( ) n+1
ϕ ρ − ϕ ρ ∆x∆y+ ρ α p (B) S f ∆t + ρ α p (B) S k ∆t =
(B) (B)
(B)
(B)
(B) (B)
(B)
(B)
i,j i,j o f,j o i,k
f=i±1/2 k=i±1/2
∑ ( ) n+1
q (m→B) ∆t∆x∆y (16)
δ i,j
δ=o-H 2 ,p-H 2
( )n+1 ( )n+1
∑ ∂H (B) ( ) n+1 ( ) n ∑ ∂H (B) ∑ [ ( ) n+1 ]
(B) (B) (B) δ (B) (B) (B) δ (B) (B)
ϕ ρ γ T − T (B) ∆x∆y + ρ γ V T S f ∆t +
∂T (B) i,j i,j ∂T (B) x;δ f,j
δ=o-H 2 ,p-H 2 i,j δ=o-H 2 ,p-H 2 i,j f=i±1/2
( (B) )n+1 ( (B) )n+1
∑ ∂H ∑ [ ( ) n+1 ] ∑ ∂H ∑ [ ( ) n+1 ]
(B) (B) δ (B) (B) (B) (B) δ (B) (B)
ρ γ V T S k ∆t = T ρ V T S f ∆t +
(B) y;δ i,k (B) x;δ f,j
∂T ∂T
i,j k=j±1/2 i,j f=i±1/2
δ=o-H 2 ,p-H 2 δ=o-H 2 ,p-H 2
( ) ( )
( (B) )n+1 (B) n+1 (B) n+1
∑ ∂H ∑ [ ( ) n+1 ] T − T
δ (B) i+1,j i,j
(B) (B)
T ρ V T (B) S k ∆t +(λ e ) −
∂T (B) y;δ i,k i+1/2,j ∆x
δ=o-H 2 ,p-H 2 i,j k=j±1/2
)
)
)
)
)
)
( (B) n+1 ( (B) n+1 ( (B) n+1 ( (B) n+1 ( (B) n+1 ( (B) n+1
T i,j − T T i,j+1 − T i,j T i,j − T
(λ e ) i−1/2,j i−1,j ∆t∆y+(λ e ) i,j+1/2 −(λ e ) i, j−1/2 i,j−1 ∆t∆x+
∆x ∆y ∆x
∑ ( ) n+1 ∑ ( ) n+1
[ ] n+1
(m→B) (B) (m→B) (m) (B)
H q − H q ∆t∆x∆y+ h mB a mB (T −T ) ∆t∆x∆y
δ δ δ δ
i,j
i,j i,j
δ=o-H 2 ,p-H 2 δ=o-H 2 ,p-H 2
(17)
n+1 n
(m) (m) (m) (m) (m) (m)
ϕ M p ϕ M p ∑ ( ) n+1
H 2 H 2 (m→B)
(18)
∆x∆y = −q ∆t∆x∆y
ZRT ZRT
− δ
(m) (m) i,j
z,r z,r δ=o-H 2 ,p-H 2
{[( )n+1
{ } (m)
[ ] n+1 [ ] n ∑ (m) ∂H δ
(m)
(m) (m)
(m)
(B)
(B)
(1−ϕ ) (1−ϕ )ρ s c v,s T (m) − (1−ϕ )ρ s c v,s T (m) ∆x∆y (1−ϕ )ϕ ρ γ δ
z,r z,r ∂T (m)
δ=o-H 2 ,p-H 2 i,j
] } ] ]
( ) n+1 ( ) n ∑ [ ( (m→B) ) n+1 ∑ [ ( (B) (m→B) ) n+1
T (m) − T (m) ∆x∆y = − H δ q ∆t∆x∆y + H q ∆t∆x∆y +
i,j i,j δ i,j δ δ i,j
δ=o-H 2 ,p-H 2 δ=o-H 2 ,p-H 2
[ (m) (B) ] n+! n+1 (m) n+1
h mB a mB (T −T ) i,j ∆t∆x∆y+(S e ) i,j ∆t∆x∆y±(S r H ) ∆t∆x∆y (19)
i,j
δ
[ ] ∑ [ ] ∑ [ ]
( (B) ) n+1 ( (B) ) n ( (B) ) n+1 ( (B) ) n+1 ( (m→B) ) n+1
(B)
(B) (B)
ϕ ρ γ − ϕ ρ γ ∆x∆y+ ρ V S f ∆t + ρ V S k ∆t = q ∆t∆x∆y
(B)
(B) (B)
i,j
o-H 2 i,j o-H 2 i,j x;o-H 2 f,j y;o-H 2 i,k o-H 2
f=i±1/2 k=i±1/2
(20)
[ ]
( ) n+1 ( (m) (m) ) n+1 ( ) n ( (m) (m) ) n ( (m→B) ) n+1
ϕ (m) ρ γ − ϕ (m) ρ γ ∆x∆y = − q +S r ∆t∆x∆y (21)
i,j o-H 2 o-H 2 i,j i,j o-H 2 o-H 2 i,j o-H 2 i,j
IMPTECR 算法将离散方程式(16)~(21)组成 数值求解模型,求解流程如图 1 所示。

