| infotek |
2022-01-24 09:30 |
十字元件热成像分析
简介:本文是以十字元件为背景光源,经过一个透镜元件成像在探测器上,并显示其热成像图。 ]5/U}Um ulJYJ+CC!
成像示意图 \l5:A]J 首先我们建立十字元件命名为Target ifZNl, ?Nql7F4 创建方法: >/bK?yT< ><c5Humr 面1 : l&xD3u^G 面型:plane .
*xq = 材料:Air WEAXqDjM 孔径:X=1.5, Y=6,Z=0.075,形状选择Box *!@x<Hf< |LH*)GrD*t
Ct+% 辅助数据: Qe.kNdT+_ 首先在第一行输入temperature :300K, uiA:(2AQ emissivity:0.1; ',Pk>f]AB- ^I?y\:. X{9o8
*V 面2 : !5!$h`g 面型:plane 1:UC\ WW 材料:Air F:GKnbY 孔径:X=1.5, Y=6,Z=0.075,形状选择Box \zL7j4 I.1l Wb4{*~ 位置坐标:绕Z轴旋转90度, 9Ib(x0_ /+O8A}
wJ*-K- 辅助数据: @6'E8NFl HW Os@!cL 首先在第一行输入temperature :300K,emissivity: 0.1; tN> B$sv ;XQ lj?: ~(^*?(Z Target 元件距离坐标原点-161mm; vaJXX UVUO}B@[S
;I71_>m 单透镜参数设定:F=100, bend=0, 位置位于坐标原点 l0xFt
~l rss.F3dK <dPxy`_ 探测器参数设定: )'`AX\ C?|3\@7 在菜单栏中选择Create/Element Primitive /plane Ltd?#HP y@\Q@
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utJVuJw:t NVWeJ+w '?3z6% 05I39/T% 元件半径为20mm*20,mm,距离坐标原点200mm。 :P~&
b P UZXcKl>u 光源创建: E?4@C"Na 13_~)V 光源类型选择为任意平面,光源半角设定为15度。 15o
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zw{<+; }Rxg E~F 我们将光源设定在探测器位置上,具体的原理解释请见本章第二部分。 yXo0z_ G mCNf]Yz 我们在位置选项又设定一行的目的是通过脚本自动控制光源在探测器平面不同划分区域内不同位置处追迹光线。 C!k9 JAa$Z i)PV{3v$J ^H6d;n 功率数值设定为:P=sin2(theta) theta为光源半角15度。我们为什么要这么设定,在第二部分会给出详细的公式推导。 <i\zfa'6 vcJb\LW 创建分析面: X+E\]X2 C2=iZ`Z>T yki51rOI* 到这里元件参数设定完成,现在我们设定元件的光学属性,在前面我们分别对第一和第二面设定的温度和发射系数,散射属性我们设定为黑朗伯,4%的散射。并分别赋予到面一和面二。 Y\Qxdq Dq%r
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^ lc}FN 到此,所有的光学结构和属性设定完成,通过光线追迹我们可以查看光线是否可以穿过元件。
QXxLe* cm 9oG FRED在探测器上穿过多个像素点迭代来创建热图 &Pg-|Ql iVi3 :7* FRED具有一个内置的可编译的Basic脚本语言。从Visual Basic脚本语言里,几乎所有用户图形界面(GUI)命令是可用这里的。FRED同样具有自动的客户端和服务器能力,它可以被调用和并调用其他可启动程序,如Excel。因此可以在探测器像素点上定义多个离轴光源,及在FRED Basic脚本语言里的For Next loops语句沿着探测器像素点向上和向下扫描来反向追迹光线,这样可以使用三维图表查看器(Tools/Open plot files in 3D chart)调用和查看数据。 ) UDJ[pL@ 将如下的代码放置在树形文件夹 Embedded Scripts, /.kna4k ^&';\O@)
fqk Dk 打开后清空里面的内容,此脚本为通用脚本适用于一切可热成像的应用。 }vUlTH ^8oc^LOa~2 绿色字体为说明文字, eMl]td rI n]C%(v!u3 '#Language "WWB-COM" P`3s\8[Q 'script for calculating thermal image map KjwY'aYwr: 'edited rnp 4 november 2005
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B!h Ebz 'declarations 2~&hstd% Dim op As T_OPERATION 9oz (=R Dim trm As T_TRIMVOLUME m,gy9$ Dim irrad(32,32) As Double 'make consistent with sampling 60aKT:KLC_ Dim temp As Double /#qs(!
d Dim emiss As Double bxhg*A Dim fname As String, fullfilepath As String f*T)*R_ g#'fd/?Q 'Option Explicit h/X5w4 U.hERe~X Sub Main Vy%
:\p+ 'USER INPUTS v :+8U[x nx = 31 #NN"(I ny = 31 xjK_zO*dLq numRays = 1000 2l)9Lz=;L minWave = 7 'microns ;N$ 0)2w maxWave = 11 'microns \>Ga-gv6/ sigma = 5.67e-14 'watts/mm^2/deg k^4 5&?KW)6 Rz fname = "teapotimage.dat" ,u&tB|,W, <K,%
y(] Print "" W%>i$:Qq
Print "THERMAL IMAGE CALCULATION" o4/I1Mq Q$3\ /mz detnode = FindFullName( "Geometry.Detector.Surface" ) '找到探测器平面节点 4z9#M;qT xMNNXPz( Print "found detector array at node " & detnode [*9YIjn !]rETP_ srcnode = FindFullName( "Optical Sources.Source 1" ) '找到光源节点 b'7z DZI] mWli}j# Print "found differential detector area at node " & srcnode Q&Z4r9+Z ]{,Gf2v;;d GetTrimVolume detnode, trm *gd?>P7\0 detx = trm.xSemiApe vnC<*k4&v dety = trm.ySemiApe #*Yi4Cn< area = 4 * detx * dety Xq,UV Print "detector array semiaperture dimensions are " & detx & " by " & dety M[YTk=IM# Print "sampling is " & nx & " by " & ny kqKj7L X-)RU? 'reset differential detector area dimensions to be consistent with sampling Sa;<B:| pixelx = 2 * detx / nx 11)/] ?/j pixely = 2 * dety / ny xS;|jj9 SetSourcePosGridRandom srcnode, pixelx / 2, pixely / 2, numRays, False PTbA1.B Print "resetting source dimensions to " & pixelx / 2 & " by " & pixely / 2 SZ5O89 Ml8 YyF/~ 'reset the source power *GbVMW[A> SetSourcePower( srcnode, Sin(DegToRad(15))^2 ) M5GY>3P$c Print "resetting the source power to " & GetSourcePower( srcnode ) & " units" <%d51~@={I ?Oy'awf_ 'zero out irradiance array bBUbw *DF) For i = 0 To ny - 1 aho'|%y) For j = 0 To nx - 1 ,4^9cFVo irrad(i,j) = 0.0 w]>"'o{{ Next j CM%|pB/z Next i 9wO/? +}_Pf{MW 'main loop \{c,,th EnableTextPrinting( False ) iNod</+"K <<
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a<I ypos = dety + pixely / 2 DtzA$|Q} For i = 0 To ny - 1 uY^v"cw/F xpos = -detx - pixelx / 2 (^sh ypos = ypos - pixely u0m5JD0/ 7 I_1 #O EnableTextPrinting( True ) '[Mlmgc5 Print i :s'o~
EnableTextPrinting( False ) GWF/[% zRwb" $_Y/'IN`k For j = 0 To nx - 1 }.0Bl&\UK .6> hD1' xpos = xpos + pixelx C%giv9a Jy \2I{I' 'shift source wL 4ZW8_ LockOperationUpdates srcnode, True 3gb|x? GetOperation srcnode, 1, op U'tE^W op.val1 = xpos aSc{Ft/O op.val2 = ypos kTnOmAw SetOperation srcnode, 1, op N>+ P WE$ LockOperationUpdates srcnode, False exfmq W7H&R, raytrace Q*]$)D3n DeleteRays bf& }8I$ CreateSource srcnode !CVuw TraceExisting 'draw "mP&8y9F i.3cj1 'radiometry {jvOHu For k = 0 To GetEntityCount()-1 x&'o ]Y If IsSurface( k ) Then ac9qj temp = AuxDataGetData( k, "temperature" ) y8G&Wg
aCi emiss = AuxDataGetData( k, "emissivity" ) <lUOJV{&\ If ( temp <> 0 And emiss <> 0 ) Then =WC-Sj{I ProjSolidAngleByPi = GetSurfIncidentPower( k ) i=YXKe6fD frac = BlackBodyFractionalEnergy ( minWave, maxWave, temp ) vu=me?m?( irrad(i,j) = irrad(i,j) + frac * emiss * sigma * temp^4 * ProjSolidAngleByPi ~A6 "sb= End If X*i/A<Y`= 4t04}vp End If 8O>}k
3P1&; Next k F8H'^3`b`U x<)G( Xe* Next j !BDUv( wu A^'T Next i F*M|<E= EnableTextPrinting( True ) F!JJ6d53y 7|YN:7iA 'write out file \#CM
<% fullfilepath = CurDir() & "\" & fname ?>af'o: Open fullfilepath For Output As #1 x[QZ@rGIW Print #1, "GRID " & nx & " " & ny !YiuwFt Print #1, "1e+308" +iy7e6P Print #1, pixelx & " " & pixely
6xoq;=o Print #1, -detx+pixelx/2 & " " & -dety+pixely/2 %JtbRs(~q v!H:^!z maxRow = nx - 1 CswE maxCol = ny - 1 K%MW6y For rowNum = 0 To maxRow ' begin loop over rows (constant X) 6k"P&AD row = "" . V$ps-t For colNum = maxCol To 0 Step -1 ' begin loop over columns (constant Y) w1r$='*I row = row & irrad(colNum,rowNum) & " " ' append column data to row string w5*Z! Next colNum ' end loop over columns 6-B 9na z>;$im Print #1, row m#f{]+6U
`2`fiKm Next rowNum ' end loop over rows (DDyK[t+VX Close #1 Q/ZkW e*C6uz9N Print "File written: " & fullfilepath 'xnnLCm. Print "All done!!" S_v(S^x6 End Sub B6]<G- HSN8O@dy 在输出报告中,我们会看到脚本对光源的孔径和功率做了修改,并最终经过31次迭代,将所有的热成像数据以dat的格式放置于: '9s5OTkN ; xY\0zQ /qU>5; 找到Tools工具,点击Open plot files in 3D chart并找到该文件 MgJ36zM Q6
?z_0 <YFY{VC( 打开后,选择二维平面图: S[,8TErz G^wtE90
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