我编写了一个带有 GUI 的疲劳分析程序。该程序获取有限元模型每个元素的单位载荷的应变信息,使用 np.genfromtxt('loadcasefilename.txt') 读取载荷工况,然后进行一些疲劳分析并将每个元素的结果保存在另一个数组中。
负载工况以文本文件形式约为 32Mb,其中有 40 个左右需要循环读取和分析。每个元素的载荷通过载荷工况数组的切片进行插值。
GUI 和疲劳分析在单独的线程中运行。当您单击疲劳分析上的“开始”时,它将开始循环疲劳分析中的载荷工况。
这让我想到了我的问题。如果我有很多元素,分析就无法完成。它多久退出取决于有多少元素,这让我认为这可能是一个内存问题。我尝试通过删除每个循环末尾的负载情况数组(删除所有作为其切片的数组之后)并运行 gc.collect() 来解决此问题,但这没有取得任何成功。
在 MatLab 中,我使用“pack”函数将工作区写入磁盘,清除它,然后在每个循环结束时重新加载它。我知道这不是一个好的做法,但它可以完成工作!我可以用 Python 做同样的事情吗?
代码如下:
for LoadCaseNo in range(len(LoadCases[0]['LoadCaseLoops'])):#range(1):#xxx
#Get load case data
self.statustext.emit('Opening current load case file...')
LoadCaseFilePath=LoadCases[0]['LoadCasePaths'][LoadCaseNo][0]
#TK: load case paths may be different
try:
with open(LoadCaseFilePath):
pass
except Exception as e:
self.statustext.emit(str(e))
LoadCaseLoops=LoadCases[0]['LoadCaseLoops'][LoadCaseNo,0]
LoadCase=np.genfromtxt(LoadCaseFilePath,delimiter=',')
LoadCaseArray=np.array(LoadCases[0]['LoadCaseLoops'])
LoadCaseArray=LoadCaseArray/np.sum(LoadCaseArray,axis=0)
#Loop through sections
for SectionNo in range(len(Sections)):#range(100):#xxx
SectionCount=len(Sections)
#Get section data
Elements=Sections[SectionNo]['elements']
UnitStrains=Sections[SectionNo]['strains'][:,1:]
Nodes=Sections[SectionNo]['nodes']
rootdist=Sections[SectionNo]['rootdist']
#Interpolate load case data at this section
NeighbourFind=rootdist-np.reshape(LoadCase[0,1:],(1,-1))
NeighbourFind[NeighbourFind<0]=1e100
nearest=np.unravel_index(NeighbourFind.argmin(), NeighbourFind.shape)
nearestcol=int(nearest[1])
Distance0=LoadCase[0,nearestcol+1]
Distance1=LoadCase[0,nearestcol+7]
MxLow=LoadCase[1:,nearestcol+1]
MxHigh=LoadCase[1:,nearestcol+7]
MyLow=LoadCase[1:,nearestcol+2]
MyHigh=LoadCase[1:,nearestcol+8]
MzLow=LoadCase[1:,nearestcol+3]
MzHigh=LoadCase[1:,nearestcol+9]
FxLow=LoadCase[1:,nearestcol+4]
FxHigh=LoadCase[1:,nearestcol+10]
FyLow=LoadCase[1:,nearestcol+5]
FyHigh=LoadCase[1:,nearestcol+11]
FzLow=LoadCase[1:,nearestcol+6]
FzHigh=LoadCase[1:,nearestcol+12]
InterpFactor=(rootdist-Distance0)/(Distance1-Distance0)
Mx=MxLow+(MxHigh-MxLow)*InterpFactor[0,0]
My=MyLow+(MyHigh-MyLow)*InterpFactor[0,0]
Mz=MzLow+(MzHigh-MzLow)*InterpFactor[0,0]
Fx=-FxLow+(FxHigh-FxLow)*InterpFactor[0,0]
Fy=-FyLow+(FyHigh-FyLow)*InterpFactor[0,0]
Fz=FzLow+(FzHigh-FzLow)*InterpFactor[0,0]
#Loop through section coordinates
for ElementNo in range(len(Elements)):
MaterialID=int(Elements[ElementNo,1])
if Materials[MaterialID]['curvefit'][0,0]!=3:
StrainHist=UnitStrains[ElementNo,0]*Mx+UnitStrains[ElementNo,1]*My+UnitStrains[ElementNo,2]*Fz
elif Materials[MaterialID]['curvefit'][0,0]==3:
StrainHist=UnitStrains[ElementNo,3]*Fx+UnitStrains[ElementNo,4]*Fy+UnitStrains[ElementNo,5]*Mz
EndIn=len(StrainHist)
Extrema=np.bitwise_or(np.bitwise_and(StrainHist[1:EndIn-1]<=StrainHist[0:EndIn-2] , StrainHist[1:EndIn-1]<=StrainHist[2:EndIn]),np.bitwise_and(StrainHist[1:EndIn-1]>=StrainHist[0:EndIn-2] , StrainHist[1:EndIn-1]>=StrainHist[2:EndIn]))
Extrema=np.concatenate((np.array([True]),Extrema,np.array([True])),axis=0)
Extrema=StrainHist[np.where(Extrema==True)]
del StrainHist
#Do fatigue analysis
self.statustext.emit('Analysing load case '+str(LoadCaseNo+1)+' of '+str(len(LoadCases[0]['LoadCaseLoops']))+' - '+str(((SectionNo+1)*100)/SectionCount)+'% complete')
del MxLow,MxHigh,MyLow,MyHigh,MzLow,MzHigh,FxLow,FxHigh,FyLow,FyHigh,FzLow,FzHigh,Mx,My,Mz,Fx,Fy,Fz,Distance0,Distance1
gc.collect()