jnjl,感激不尽啊!
我正在检查中。我也做了一个简单的二维问题(见下图),通过这个问题的反复试算,估计可能存在如下问题:
1)网格质量 如果采用全四面体网格可能存在问题,特别在热梯度很大时。建模网格划得不是很好,不知道怎么评定
2)flotran的设置。
3)求解器和求解准则的设置。msu,supg等
该二维模型很粗糙。在边线上施加热流密度q=15000w/m2时,温度也很高,而且不管入口速度的多大(一定范围),感觉好像热量就是进不了流体中,问题和三维的好像差不多。命令流如下:
/prep7
/units,si
et,1,141
QW = 15000.0 ! WALL HEAT FLUX (W/M**2)
RHO =1.1 !13529.0 ! FLUID DENSITY (KG/M**3)
MU =1.91e-5 !1.523E-03 ! FLUID VISCOSITY (KG/(M*SEC))
K =2.67e-2 !8.54 ! FLUID THERMAL CONDUCTIVITY (W/(M*K))
CP =1004 !139.3
rectng,0,0.2,0,0.05
rectng,0.4,1.5,0,0.1
a,2,3,8,5
lsel,s,,,1,3,2
lesize,all,,,20
lsel,s,,,2,8,2
lesize,all,,,40,-3
lsel,s,,,5,7,2
lesize,all,,,100,-2
lsel,s,,,9,10
lesize,all,,,30
!esize,0.1
amesh,all
nsel,all
esel,all
lsel,s,,,4
nsll,,1
d,all,vx,10
d,all,vy,0
d,all,temp,300
lsel,s,,,6
nsll,,1
d,all,pres,0
lsel,s,,,1,5,4
lsel,a,,,10
nsll,,1
d,all,vy,0
d,all,vx,0
lsel,s,,,3,7,4
lsel,a,,,9
nsll,,1
d,all,vx,0
d,all,vy,0
sf,all,hflux,QW
allsel
finish
/SOLU
FLDATA,ITER,EXEC,200 ! # OF GLOBAL ITERATIONS
FLDATA,ITER,CHEC,50 ! CHECKPOINT FREQUENCY
fldata,advm,mome,msu
fldata,advm,temp,msu
fldata,advm,pres,colg
fldata,RELX,EVIS,0.1
FLDATA,TEMP,NOMI,300 ! NOMINAL TEMPERATURE
FLDATA,NOMI,DENS,RHO ! FLUID DENSITY
FLDATA,NOMI,VISC,MU ! FLUID VISCOSITY
FLDATA,NOMI,COND,K ! FLUID THERMAL CONDUCTIVITY
FLDATA,NOMI,SPHT,CP ! FLUID SPECIFIC HEAT
fldata,temp,bulk,300
fldata,mir,mome,0.5
SOLVE
/out
FLDATA,ITER,EXEC,50 ! # OF GLOBAL ITERATIONS
FLDATA,SOLU,TEMP,T ! ACTIVATE ENERGY EQUATION
FLDATA,SOLU,FLOW,F ! DEACTIVATE FLOW EQUATIONS
FLDATA,RELX,TEMP,1.0 ! NO RELAXATION FOR TEMP
solve
FINISH
!!!!!!!!!!!!!!!!!!!!!!!!!1
To festival:不是。是一个热流问题。你可以先看看这个二维问题。非常感谢你的参与! |