<div dir="ltr">I'm sorry that I have to ask for help again. Actually I'm trying to model different electrical applications. So I use your example of a inductive heated tube and changed the geometry to a ring that surrounds the inductor. Theoretically there should be induced a small current caused by the <span style="text-align:center;background-color:rgb(255,254,239);font-family:Arial,sans-serif;font-size:12px;line-height:18px">transverse-field. But in my calculation the current in the ring is equal to zero.</span><br>
<div><span style="text-align:center;background-color:rgb(255,254,239);font-family:Arial,sans-serif;font-size:12px;line-height:18px"><br></span></div><div><span style="text-align:center;background-color:rgb(255,254,239);font-family:Arial,sans-serif;font-size:12px;line-height:18px">It would be great, if you could give me an advice.</span></div>
<div><span style="text-align:center;background-color:rgb(255,254,239);font-family:Arial,sans-serif;font-size:12px;line-height:18px"><br></span></div><div><span style="text-align:center;background-color:rgb(255,254,239);font-family:Arial,sans-serif;font-size:12px;line-height:18px">Thank you once again</span></div>
<div><span style="text-align:center;background-color:rgb(255,254,239);font-family:Arial,sans-serif;font-size:12px;line-height:18px"><br></span></div><div><span style="text-align:center;background-color:rgb(255,254,239);font-family:Arial,sans-serif;font-size:12px;line-height:18px">Maximilian</span></div>
<div><span style="text-align:center;background-color:rgb(255,254,239);font-family:Arial,sans-serif;font-size:12px;line-height:18px"><br></span></div><div><div style="font-family:arial,sans-serif;font-size:13px">/*+++++++++++++++++++++++++++++++++++++++++++++</div>
<div style="font-family:arial,sans-serif;font-size:13px">++++++++++++ .GEO +++++++++++</div><div style="font-family:arial,sans-serif;font-size:13px">++++++++++++++++++++++++++++++++++++++</div></div><div><span style="text-align:center;background-color:rgb(255,254,239);font-family:Arial,sans-serif;font-size:12px;line-height:18px"><br>
</span></div><div><span style="text-align:center;background-color:rgb(255,254,239);font-size:12px;line-height:18px"><font face="Arial, sans-serif"><div>lc = 0.03; // Mesh characteristic length</div><div>lc2 = lc/2;</div><div>
lc3 = 0;</div><div>front3d = 1; // Set to 1 if Frontal 3D mesh algorithm is used</div><div>nn = (1./lc)/4.; // Mesh subdivisions per turn, used with Frontal 3D</div><div> </div><div>If(front3d == 1)</div><div>Mesh.Algorithm3D = 4; // Frontal 3D</div>
<div>EndIf</div><div> </div><div>DefineConstant</div><div>[</div><div> turns = {20, Label "Number of coil turns"},</div><div> r = {0.11, Label "Coil radius"},</div><div> rc = {0.01, Label "Coil wire radius"},</div>
<div> hc = {0.2, Label "Coil height"},</div><div> ht = {0.3, Label "Tube height"},</div><div> rt1 = {0.13, Label "Tube internal radius"},</div><div> rt2 = {0.20, Label "Tube external radius"},</div>
<div> lb = {1, Label "Infinite box width"}</div><div> left = {1, Label "Terminals on the left?"}</div><div>];</div><div> </div><div>// inductor</div><div>lc = 0.015; // Mesh characteristic length</div>
<div>lc2 = lc;</div><div>lc3 = 0;</div><div>front3d = 1; // Set to 1 if Frontal 3D mesh algorithm is used</div><div>nn = (1./lc)/4.; // Mesh subdivisions per turn, used with Frontal 3D</div><div><br></div><div>If(front3d == 1)</div>
<div>Mesh.Algorithm3D = 4; // Frontal 3D</div><div>EndIf</div><div><br></div><div>DefineConstant</div><div>[</div><div> turns = {5, Label "Number of coil turns"},</div><div> r = {0.11, Label "Coil radius"},</div>
<div> rc = {0.01, Label "Coil wire radius"},</div><div> hc = {0.2, Label "Coil height"},</div><div> ht = {0.3, Label "Tube height"},</div><div> rt1 = {0.081, Label "Tube internal radius"},</div>
<div> rt2 = {0.092, Label "Tube external radius"},</div><div> lb = {1, Label "Infinite box width"}</div><div> left = {1, Choices{0,1}, Label "Terminals on the left?"}</div><div>];</div><div><br>
</div><div>// inductor</div><div>p = newp;</div><div>Point(p)={0, -r, -hc/2, lc};</div><div>Point(p+1)={0, -r+rc, -hc/2, lc};</div><div>Point(p+2)={0, -r, -hc/2+rc, lc};</div><div>Point(p+3)={0, -r-rc, -hc/2, lc};</div><div>
Point(p+4)={0, -r, -hc/2-rc,lc};</div><div>c = newl;</div><div>Circle(c) = {p+1,p,p+2};</div><div>Circle(c+1) = {p+2,p,p+3};</div><div>Circle(c+2) = {p+3,p,p+4};</div><div>Circle(c+3) = {p+4,p,p+1};</div><div>ll = newll;</div>
<div>Line Loop(ll) = {c,c+1,c+2,c+3};</div><div>s = news;</div><div>Plane Surface(s) = {ll};</div><div>tmp[] = {s};</div><div>vol_coil[] = {};</div><div>For j In {1:4*turns+(left?2:0)}</div><div>If(front3d == 1)</div><div>
tmp[] = Extrude { {0,0,hc/turns/4}, {0,0,1} , {0,0,0} , Pi/2}</div><div> { Surface {tmp[0]}; Layers {nn / 4}; };</div><div>EndIf</div><div>If(front3d == 0)</div><div> tmp[] = Extrude { {0,0,hc/turns/4}, {0,0,1} , {0,0,0} , Pi/2}</div>
<div> { Surface {tmp[0]}; };</div><div>EndIf</div><div> vol_coil[] += tmp[1];</div><div>EndFor</div><div>If(front3d == 1)</div><div>tmp[] = Extrude {(left?-1:1)*lb/2, 0, 0} { Surface{tmp[0]}; Layers{nn}; };</div>
<div>EndIf</div><div>If(front3d == 0)</div><div>tmp[] = Extrude {(left?-1:1)*lb/2, 0, 0} { Surface{tmp[0]}; };</div><div>EndIf</div><div>vol_coil[] += tmp[1];</div><div>out = tmp[0];</div><div>If(front3d == 1)</div><div>tmp[] = Extrude {-lb/2, 0, 0} { Surface{s}; Layers{nn}; };</div>
<div>EndIf</div><div>If(front3d == 0)</div><div>tmp[] = Extrude {-lb/2, 0, 0} { Surface{s}; };</div><div>EndIf</div><div>vol_coil[] += tmp[1];</div><div>in = tmp[0];</div><div><br></div><div>rk=0.05;</div><div><br></div><div>
// tube</div><div>p = newp;</div><div><br></div><div>Point(p) = {0, 0, -hc/8, lc};</div><div>Point(p+1) = {rt1*Sin(Pi/2), rt1*Cos(Pi/2), -hc/8, lc2};</div><div>Point(p+2) = {rt1*Sin(0), rt1*Cos(0), -hc/8, lc2};</div><div>
Point(p+3) = {rt1*Sin(-Pi/2), rt1*Cos(-Pi/2), -hc/8, lc2};</div><div>Point(p+4) = {rt1*Sin(Pi), rt1*Cos(Pi), -hc/8, lc2};</div><div>Point(p+5) = {rt2*Sin(Pi/2), rt2*Cos(Pi/2), -hc/8, lc2};</div><div>Point(p+6) = {rt2*Sin(0), rt2*Cos(0), -hc/8, lc2};</div>
<div>Point(p+7) = {rt2*Sin(-Pi/2), rt2*Cos(-Pi/2), -hc/8, lc2};</div><div>Point(p+8) = {rt2*Sin(Pi), rt2*Cos(Pi), -hc/8, lc2};</div><div><br></div><div>c = newc;</div><div>Circle(c) = {p+1, p, p+2};</div><div>Circle(c+1) = {p+2, p, p+3};</div>
<div>Circle(c+2) = {p+3, p, p+4};</div><div><br></div><div>Circle(c+3) = {p+4, p, p+1};</div><div><br></div><div>Circle(c+4) = {p+5, p, p+6};</div><div>Circle(c+5) = {p+6, p, p+7};</div><div>Circle(c+6) = {p+7, p, p+8};</div>
<div><br></div><div>Circle(c+7) = {p+8, p, p+5};</div><div><br></div><div>ll = newll;</div><div><br></div><div>Line Loop(ll) = {c+4, c+5, c+6, c+7, -c, -(c+1), -(c+2), -(c+3)};</div><div><br></div><div>s = news;</div><div>
Plane Surface(s) = {ll};</div><div>If(front3d == 1)</div><div>tmp[] = Extrude {0,0,hc/4}{ Surface{s}; Layers{nn}; };</div><div>EndIf</div><div>If(front3d == 0)</div><div>tmp[] = Extrude {0,0,hc/4}{ Surface{s}; };</div><div>
EndIf</div><div>vol_tube = tmp[1];</div><div><br></div><div>// box</div><div>p = newp;</div><div>Point(p) = {-lb/2,-lb/2,-lb/2, lc3};</div><div>Point(p+1) = {lb/2,-lb/2,-lb/2, lc3};</div><div>Point(p+2) = {lb/2,lb/2,-lb/2, lc3};</div>
<div>Point(p+3) = {-lb/2,lb/2,-lb/2, lc3};</div><div>Point(p+4) = {-lb/2,-lb/2,lb/2, lc3};</div><div>Point(p+5) = {lb/2,-lb/2,lb/2, lc3};</div><div>Point(p+6) = {lb/2,lb/2,lb/2, lc3};</div><div>Point(p+7) = {-lb/2,lb/2,lb/2, lc3};</div>
<div>l = newl;</div><div>Line(l) = {p,p+1};</div><div>Line(l+1) = {p+1,p+2};</div><div>Line(l+2) = {p+2,p+3};</div><div>Line(l+3) = {p+3,p};</div><div>Line(l+4) = {p+4,p+5};</div><div>Line(l+5) = {p+5,p+6};</div><div>Line(l+6) = {p+6,p+7};</div>
<div>Line(l+7) = {p+7,p+4};</div><div>Line(l+8) = {p, p+4};</div><div>Line(l+9) = {p+1, p+5};</div><div>Line(l+10) = {p+2, p+6};</div><div>Line(l+11) = {p+3, p+7};</div><div>ll = newll;</div><div>Line Loop(ll) = Boundary {Surface{in}; };</div>
<div>Line Loop(ll+1) = {l+8, -(l+7), -(l+11), l+3};</div><div>Line Loop(ll+2) = Boundary {Surface{out}; };</div><div>Line Loop(ll+3) = {l+9, l+5, -(l+10), -(l+1)};</div><div>Line Loop(ll+4) = {l,l+1,l+2,l+3};</div><div>Line Loop(ll+5) = {l+4,l+5,l+6,l+7};</div>
<div>Line Loop(ll+6) = {l+2, l+11, -(l+6), -(l+10)};</div><div>Line Loop(ll+7) = {l, l+9, -(l+4), -(l+8)};</div><div>s = news;</div><div>tmp[] = {ll+1, ll};</div><div>If(left)</div><div> tmp[] += ll+2;</div><div>EndIf</div>
<div>Plane Surface(s) = tmp[];</div><div>tmp[] = {ll+3};</div><div>If(!left)</div><div> tmp[] += ll+2;</div><div>EndIf</div><div>Plane Surface(s+1) = tmp[];</div><div>Plane Surface(s+2) = {ll+4};</div><div>Plane Surface(s+3) = {ll+5};</div>
<div>Plane Surface(s+4) = {ll+6};</div><div>Plane Surface(s+5) = {ll+7};</div><div>sl = newsl;</div><div>skin_coil[] = CombinedBoundary{ Volume{vol_coil[]}; };</div><div>skin_coil[] -= {in, out};</div><div>Surface Loop(sl) = {s:s+5,skin_coil[]};</div>
<div>Surface Loop(sl+1) = CombinedBoundary{ Volume{vol_tube[]}; };</div><div>v = newv;</div><div>Volume(v) = {sl, sl+1};</div><div><br></div><div>COIL = 1000;</div><div>TUBE = 1001;</div><div>AIR = 1002;</div><div>SKIN_COIL = 2000;</div>
<div>SKIN_TUBE = 2001;</div><div>IN = 2002;</div><div>OUT = 2003;</div><div>INF = 2004;</div><div>Physical Volume(COIL) = {vol_coil[]};</div><div>Physical Volume(TUBE) = {vol_tube[]};</div><div>Physical Volume(AIR) = {v};</div>
<div>Physical Surface(SKIN_COIL) = {skin_coil[]};</div><div>Physical Surface(SKIN_TUBE) = CombinedBoundary{ Volume{vol_tube[]}; };</div><div>Physical Surface(IN) = in;</div><div>Physical Surface(OUT) = out;</div><div>Physical Surface(INF) = {s:s+5};</div>
<div><br></div><div><br></div><div>// Cohomology computation for the T-Omega method</div><div>Cohomology(1) {{AIR, TUBE},{}};</div><div>Cohomology(1) {{AIR, COIL},{}};</div><div><br></div><div>// Alternative cohomology computation for the T-Omega method</div>
<div>// - Faster, but requires cohomology basis selection</div><div>//Homology(2) {{TUBE},{SKIN_TUBE}};</div><div>//Homology(1) {{SKIN_COIL},{}};</div><div>//Cohomology(1) {{AIR},{}};</div><div><br></div><div>// Cohomology computation for the A-V method</div>
<div>Cohomology(1) {{COIL},{IN, OUT}};</div><div>Cohomology(1) {{TUBE},{}};</div></font></span></div></div>