inertial electrostatic confinement fusion reactor liquid cooled ion accelerating grid design
DESCRIPTION
Inertial Electrostatic Confinement Fusion Reactor Liquid Cooled Ion Accelerating Grid Design A. Seltzman, Georgia Institute of Technology. Abstract:. Reactor Design:. Results:. - PowerPoint PPT PresentationTRANSCRIPT
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Inertial Electrostatic Confinement Fusion ReactorLiquid Cooled Ion Accelerating Grid DesignA. Seltzman, Georgia Institute of TechnologyAbstract:Reactor Design:IEC Fusion Overview:Results:Future Work: Traditional inertial electrostatic confinement (IEC) fusion reactor designs utilize an ion accelerating grid fabricated out of a refractory metal capable of operating at high temperatures to radiate off heat imparted by ion-grid collisions. Unfortunately, the high gird temperature allows for a substantial thermionic electron emission current, requiring a high power draw and significantly reducing reactor efficiency. Further, electrons emitted from the grid are accelerated into the reactor shell where they generate a significant amount of bremsstrahlung x-rays requiring additional shielding and increasing system size and weight. Presented is a novel modification to the traditional implementation of IEC fusion reactor, designed to improve operating efficiency by reducing electron emission from the grid. A liquid cooled grid design is utilized to reduce thermionic electron emission, allowing for higher plasma densities, and greater input power while improving system efficiency and reducing x-ray output. The resulting low grid temperatures substantially reduce thermionic electron emission and greatly improve reactor efficiency by reducing current draw from the central grid. The reduction of thermionic electron emission will eliminate the majority of bremsstrahlung x-ray generation thereby reducing shielding requirements. By measuring the heat deposited into the coolant, the grid cooling system may also be used as a diagnostic tool to study the physics involved in IEC reactors. In this manner, grid transparency may be directly measured as a function of ion bombardment heating. By modifying the confinement scheme of the reactor and subsequently evaluating the energy flux to the grid through ion collisions, greater energy and particle confinement times may be obtained.Deuterium Plasma: 13kV, 5mA, 16mTorrIEC Reactor Core DesignMark 3 IEC Reactor CoreCooled Ion Accelerating Grid DesignGrid Cooling SystemIon Accelerating GridECRF Ion Injector DesignECRF Ion Injector AssemblyReactor DesignModular, portable designHigh efficiency neutron productionCooled grid design reduces unwanted x-ray emissionOn demand deuterium generation from heavy water reserveOnboard ECRF drive systemLabview Control, USB interfaceNeutron DetectorVacuum EnvelopeFluorinert MicropumpPrimary Cooling RadiatorVacuum HubECRF Drive AmplifierAccelerating Grid SystemECRF InjectorGrid Cooling SystemPrimary cooling loop radiator removes heat from waterWater cooled Fluorinert chiller assemblyThermoelectric chiller assembly allows compact, high performance cooling of gridFluorinert grid cooling loopCooled Grid AssemblyLow operating temperature to reduce thermionic electron emission current.High voltage bias (-50kV)Three ring grid fabricated from 1/16 OD stainless steel tubeNon-conductive Fluorinert coolantHigh flow rate (1ml/s at 80 PSI)Ceramic cooling system isolationVacuum compatible alumina ceramic feedthroughsECRF Injector SystemRF drive system operational, Injector system in testingRF ionization of X-mode electron cyclotron resonance at 880MHz Provides low pressure stabilityIncreases plasma density and energy while reducing ion-grid collisionsFluorinert ChillerResults and design documentation posted at:www.rtftechnologies.orgIon TrajectoryProblem to be Solved:Grid heating due to ion bombardment causes thermionic electron emission, thereby increasing reactor power draw and generating unwanted x-ray radiation.Ion Bombardment HeatingReactor OperationalDeuterium fusion detected via neutron generationCooled grid remains below 45C at 155W drive power.Grid serves as diagnostic tool to determine fraction of drive power dissipated into grid heatingDiagnostic Use of Grid CoolingBy measuring coolant feed and return temperature, ion bombardment heating power and grid temperature may be directly measuredBy comparing grid heating to reactor drive power, a direct measurement of grid transparency may be obtainedThe resulting trends in heating vs. input power and pressure may be used to determine stable operating regions for non-cooled grid reactors
Grid Cooling DataAs plasma impedance increases, grid heating power fraction decreasesAs plasma density decreases, slope of Grid Heating vs. Drive Power decreasesAs drive power increases, plasma impedance decreases
Solution:A liquid cooled ion accelerating grid remains cool at high operating power, allowing increased plasma density and higher operating efficiency by eliminating thermionic electron emission.Thermionic Electron EmissionDeuterium FusionCentral grid negatively biasedIons oscillate in electrostatic fieldIons collide at focal point and fuseFusion generated high energy neutrons and protonsGrid HeatingA fraction of the accelerated ions collide with the grid heating it.A radiatively cooled grid will operate at high temperaturesAt high temperatures the grid emits a large thermionic electron current, generating a substantial power drawEmitted electrons are accelerated into the reactor shell where they generate bremsstrahlung x-rays.
Chart1
4.578753.357757.93654.4261251.6788752.74725
7.631258.5478.852253.6632.136752.899875
10.6837512.97312511.14162513.2783752.747254.426125
10.53112519.38337515.10987515.567753.510375
3.6632.1367521.6727518.7728754.731375
5.6471257.936525.030523.504256.41025
17.09411.599510.836375
3.81562517.5518752.13675
4.7313753.663
5.9523755.036625
9.0048757.326
12.362625
15.873
31mTorr
25mTorr
20mTorr
16mTorr
14.5mTorr
13mTorr
P: Drive Power(W), Ion source on
H: Grid Heating (W)
y(25mTorr) = 0.0721x1.2553R2 = 0.9822
y(20mTorr) = 0.0816x1.1471R2 = 0.9985
y(16mTorr) = 0.1139x1.0468R2 = 0.9984
y(14.5mTorr) = 0.0937x1.0712R2 = 0.9926
Sheet1
Coolant:Fluorinert FC-40
Pressure:60PSI
Flow:0.75cc/sec
Density:1850kg/m^3
Specific Heat1100J/(kg*C)
Power Disipation:1.52625W/C
Data Points:
3/27/08 data
Pres(Torr)Grid(kV)Grid(mA)Power(W)TinToutTdeltaHeating(W)H/PAVG H/PV(kV)/I(mA)
25mTorr Data =>0.0243.95.220.2823.8262.23.357750.16556952660.75
0.0253.9103923.829.45.68.5470.21915384620.39
0.0254.11561.523.932.48.512.9731250.2109451220.2733333333
0.0264.5209024.537.212.719.3833750.21537083330.225
0.0244.53.616.224.826.21.42.136750.13189814811.25
0.0254.6104624.930.15.27.93650.17253260870.18591168080.46
16mTorr Data =>0.016843225.328.22.94.4261250.13831640622
25mR/h at VP0.0168.23.427.8825.427.82.43.6630.1313845052.4117647059
p (mTorr)exp
3/31/08 data251.2553
Pres(Torr)Grid(kV)Grid(mA)Power(W)TinToutTdeltaHeating(W)H/PAVG H/PV(kV)/I(mA)201.1471
31mtorr31.31.581015.823.226.234.578750.28979430380.158161.0468
31.31.915.529.4523.328.357.631250.25912563670.1225806452141.0712
31.32.1518.339.34523.430.4710.683750.27154022110.1174863388130.962
31.32.217.738.9423.530.46.910.5311250.27044491530.1242937853
31.32.56.215.523.726.12.43.6630.23632258060.4032258065
31.32.681026.823.827.53.75.6471250.21071361940.268
31.32.96257423.935.111.217.0940.2310.1184
31.32.85.214.5624.226.72.53.8156250.26206215660.5384615385
31.337.823.424.327.43.14.7313750.20219551280.3846153846
31.33.089.930.49224.328.23.95.9523750.1952110390.3111111111
31.33.314.547.8524.330.25.99.0048750.18818965520.2275862069
31.33.351963.6524.432.58.112.3626250.19422820110.1763157895
31.33.4721.474.25824.434.810.415.8730.2137547470.23266019910.1621495327
20mTorr20.85.79.755.2924.729.95.27.93650.14354313620.587628866
20.85.8105824.730.55.88.852250.1526250.58
20.85.8512.472.5424.832.17.311.1416250.15359284530.4717741935
20.85.981695.6824.834.79.915.1098750.15792093440.37375
20.86.121.4130.5424.83914.221.672750.16602382410.285046729
20.86.2223.5146.172541.416.425.03050.1712423890.15749135480.2646808511
pAVG H/P
16mTorr168.411.294.0825.634.38.713.2783750.14113919010.7531.30.2326601991
168.4113.1110.17125.735.910.215.567750.14130533440.6419847328250.1859116808
168.3515.6130.2625.73812.318.7728750.14411849380.5352564103200.1574913548
17.68.1519.2156.4825.841.215.423.504250.15020609660.4244791667160.1417915626
168.89.886.2426.233.87.611.59950.1345025510.8979591837140.1202911405
8.814.3125.8426.137.611.517.5518750.13947770980.14179156260.6153846154130.1018718839
14mTorr14.58.41.714.2826.327.41.11.6788750.11756827734.9411764706
14.58.6217.226.227.61.42.136750.12422965124.3
14.58.72.723.4926.2281.82.747250.1169540233.2222222222
14.58.783.429.85226.228.52.33.5103750.11759262362.5823529412
14.58.94.540.0526.229.33.14.7313750.11813670411.9777777778
14.595.650.426.130.34.26.410250.12718751.6071428571
14.599.383.726.233.37.110.8363750.12946684590.9677419355
14.58.652.420.7626.527.91.42.136750.10292630063.6041666667
14.58.83.530.826.428.82.43.6630.11892857142.5142857143
14.58.94.640.9426.429.73.35.0366250.12302454811.9347826087
14.596.457.626.531.34.87.3260.12718750.12029114051.40625
13mTorr1310.82.52726.528.31.82.747250.101754.32
10.82.628.0826.428.31.92.8998750.10327190174.1538461538
500mR/h at VP1144426.429.32.94.4261250.100593750.10187188392.75
Sheet1
31mTorr
25mTorr
20mTorr
16mTorr
14.5mTorr
13mTorr
P: Drive Power(W), Ion source on
H: Grid Heating (W)
y(25mTorr) = 0.0721x1.2553R2 = 0.9822
y(20mTorr) = 0.0816x1.1471R2 = 0.9985
y(16mTorr) = 0.1139x1.0468R2 = 0.9984
y(14.5mTorr) = 0.0937x1.0712R2 = 0.9926
Sheet2
31mTorr
25mTorr
20mTorr
16mTorr
14.5mTorr
13mTorr
H: Drive Current(mA), Ion source on
H: Grid Heating (W)
Sheet3
Pressure (mTorr)
P-H Curve Exponent
Pressure (mTorr)
H/P: Grid Heating (W) / Drive Power(W)
31mTorr
25mTorr
20mTorr
16mTorr
14.5mTorr
13mTorr
H/P: Grid Heating (W) / Drive Power(W)
Z(MOhm): Drive Voltage(kV) / Drive Current(mA)
31mTorr
25mTorr
20mTorr
16mTorr
14.5mTorr
13mTorr
Z(MOhm): Drive Voltage(kV) / Drive Current(mA)
H/P: Grid Heating (W) / Drive Power(W)
Chart5
0.28979430380.16556952660.14354313620.13831640620.11756827730.10175
0.25912563670.21915384620.1526250.1313845050.12422965120.1032719017
0.27154022110.2109451220.15359284530.14113919010.1169540230.10059375
0.27044491530.21537083330.15792093440.14130533440.1175926236
0.23632258060.13189814810.16602382410.14411849380.1181367041
0.21071361940.17253260870.1712423890.15020609660.1271875
0.2310.1345025510.1294668459
0.26206215660.13947770980.1029263006
0.20219551280.1189285714
0.1952110390.1230245481
0.18818965520.1271875
0.1942282011
0.213754747
31mTorr
25mTorr
20mTorr
16mTorr
14.5mTorr
13mTorr
Z(MOhm): Drive Voltage(kV) / Drive Current(mA)
H/P: Grid Heating (W) / Drive Power(W)
Sheet1
Coolant:Fluorinert FC-40
Pressure:60PSI
Flow:0.75cc/sec
Density:1850kg/m^3
Specific Heat1100J/(kg*C)
Power Disipation:1.52625W/C
Data Points:
3/27/08 data
Pres(Torr)Grid(kV)Grid(mA)Power(W)TinToutTdeltaHeating(W)H/PAVG H/PV(kV)/I(mA)
25mTorr Data =>0.0243.95.220.2823.8262.23.357750.16556952660.75
0.0253.9103923.829.45.68.5470.21915384620.39
0.0254.11561.523.932.48.512.9731250.2109451220.2733333333
0.0264.5209024.537.212.719.3833750.21537083330.225
0.0244.53.616.224.826.21.42.136750.13189814811.25
0.0254.6104624.930.15.27.93650.17253260870.18591168080.46
16mTorr Data =>0.016843225.328.22.94.4261250.13831640622
25mR/h at VP0.0168.23.427.8825.427.82.43.6630.1313845052.4117647059
p (mTorr)exp
3/31/08 data251.2553
Pres(Torr)Grid(kV)Grid(mA)Power(W)TinToutTdeltaHeating(W)H/PAVG H/PV(kV)/I(mA)201.1471
31mtorr31.31.581015.823.226.234.578750.28979430380.158161.0468
31.31.915.529.4523.328.357.631250.25912563670.1225806452141.0712
31.32.1518.339.34523.430.4710.683750.27154022110.1174863388130.962
31.32.217.738.9423.530.46.910.5311250.27044491530.1242937853
31.32.56.215.523.726.12.43.6630.23632258060.4032258065
31.32.681026.823.827.53.75.6471250.21071361940.268
31.32.96257423.935.111.217.0940.2310.1184
31.32.85.214.5624.226.72.53.8156250.26206215660.5384615385
31.337.823.424.327.43.14.7313750.20219551280.3846153846
31.33.089.930.49224.328.23.95.9523750.1952110390.3111111111
31.33.314.547.8524.330.25.99.0048750.18818965520.2275862069
31.33.351963.6524.432.58.112.3626250.19422820110.1763157895
31.33.4721.474.25824.434.810.415.8730.2137547470.23266019910.1621495327
20mTorr20.85.79.755.2924.729.95.27.93650.14354313620.587628866
20.85.8105824.730.55.88.852250.1526250.58
20.85.8512.472.5424.832.17.311.1416250.15359284530.4717741935
20.85.981695.6824.834.79.915.1098750.15792093440.37375
20.86.121.4130.5424.83914.221.672750.16602382410.285046729
20.86.2223.5146.172541.416.425.03050.1712423890.15749135480.2646808511
pAVG H/P
16mTorr168.411.294.0825.634.38.713.2783750.14113919010.7531.30.2326601991
168.4113.1110.17125.735.910.215.567750.14130533440.6419847328250.1859116808
168.3515.6130.2625.73812.318.7728750.14411849380.5352564103200.1574913548
17.68.1519.2156.4825.841.215.423.504250.15020609660.4244791667160.1417915626
168.89.886.2426.233.87.611.59950.1345025510.8979591837140.1202911405
8.814.3125.8426.137.611.517.5518750.13947770980.14179156260.6153846154130.1018718839
14mTorr14.58.41.714.2826.327.41.11.6788750.11756827734.9411764706
14.58.6217.226.227.61.42.136750.12422965124.3
14.58.72.723.4926.2281.82.747250.1169540233.2222222222
14.58.783.429.85226.228.52.33.5103750.11759262362.5823529412
14.58.94.540.0526.229.33.14.7313750.11813670411.9777777778
14.595.650.426.130.34.26.410250.12718751.6071428571
14.599.383.726.233.37.110.8363750.12946684590.9677419355
14.58.652.420.7626.527.91.42.136750.10292630063.6041666667
14.58.83.530.826.428.82.43.6630.11892857142.5142857143
14.58.94.640.9426.429.73.35.0366250.12302454811.9347826087
14.596.457.626.531.34.87.3260.12718750.12029114051.40625
13mTorr1310.82.52726.528.31.82.747250.101754.32
10.82.628.0826.428.31.92.8998750.10327190174.1538461538
500mR/h at VP1144426.429.32.94.4261250.100593750.10187188392.75
Sheet1
000000
000000
000000
00000
00000
00000
000
000
00
00
00
0
0
31mTorr
25mTorr
20mTorr
16mTorr
14.5mTorr
13mTorr
P: Drive Power(W), Ion source on
H: Grid Heating (W)
y(25mTorr) = 0.0721x1.2553R2 = 0.9822
y(20mTorr) = 0.0816x1.1471R2 = 0.9985
y(16mTorr) = 0.1139x1.0468R2 = 0.9984
y(14.5mTorr) = 0.0937x1.0712R2 = 0.9926
Sheet2
000000
000000
000000
00000
00000
00000
000
000
00
00
00
0
0
31mTorr
25mTorr
20mTorr
16mTorr
14.5mTorr
13mTorr
H: Drive Current(mA), Ion source on
H: Grid Heating (W)
Sheet3
0
0
0
0
0
Pressure (mTorr)
Power-Heating Curve Exponent
00
00
00
00
00
0
Average H/P
H/P Exponent
Pressure (mTorr)
H/P: Grid Heating (W) / Drive Power(W)
Power-Heating Curve Exponent
000000
000000
000000
00000
00000
00000
000
000
00
00
00
0
0
31mTorr
25mTorr
20mTorr
16mTorr
14.5mTorr
13mTorr
H/P: Grid Heating (W) / Drive Power(W)
Z(MOhm): Drive Voltage(kV) / Drive Current(mA)
000000
000000
000000
00000
00000
00000
000
000
00
00
00
0
0
31mTorr
25mTorr
20mTorr
16mTorr
14.5mTorr
13mTorr
Z(MOhm): Drive Voltage(kV) / Drive Current(mA)
H/P: Grid Heating (W) / Drive Power(W)
Chart2
0.1580.750.58762886624.94117647064.32
0.12258064520.390.582.41176470594.34.1538461538
0.11748633880.27333333330.47177419350.753.22222222222.75
0.12429378530.2250.373750.64198473282.5823529412
0.40322580651.250.2850467290.53525641031.9777777778
0.2680.460.26468085110.42447916671.6071428571
0.11840.89795918370.9677419355
0.53846153850.61538461543.6041666667
0.38461538462.5142857143
0.31111111111.9347826087
0.22758620691.40625
0.1763157895
0.1621495327
31mTorr
25mTorr
20mTorr
16mTorr
14.5mTorr
13mTorr
P: Drive Power(W)
Z(MOhm): Drive Voltage(kV) / Drive Current(mA)
Sheet1
Coolant:Fluorinert FC-40
Pressure:60PSI
Flow:0.75cc/sec
Density:1850kg/m^3
Specific Heat1100J/(kg*C)
Power Dissipation:1.52625W/C
Data Points:
3/27/08 data
Pres(Torr)Grid(kV)Grid(mA)Power(W)TinToutTdeltaHeating(W)H/PAVG H/PV(kV)/I(mA)
25mTorr Data =>0.0243.95.220.2823.8262.23.357750.16556952660.75
0.0253.9103923.829.45.68.5470.21915384620.39
0.0254.11561.523.932.48.512.9731250.2109451220.2733333333
0.0264.5209024.537.212.719.3833750.21537083330.225
0.0244.53.616.224.826.21.42.136750.13189814811.25
0.0254.6104624.930.15.27.93650.17253260870.18591168080.46
16mTorr Data =>0.016843225.328.22.94.4261250.13831640622
25mR/h at VP0.0168.23.427.8825.427.82.43.6630.1313845052.4117647059
p (mTorr)exp
3/31/08 data251.2553
Pres(Torr)Grid(kV)Grid(mA)Power(W)TinToutTdeltaHeating(W)H/PAVG H/PV(kV)/I(mA)201.1471
31mtorr31.31.581015.823.226.234.578750.28979430380.158161.0468
31.31.915.529.4523.328.357.631250.25912563670.1225806452141.0712
31.32.1518.339.34523.430.4710.683750.27154022110.1174863388130.962
31.32.217.738.9423.530.46.910.5311250.27044491530.1242937853
31.32.56.215.523.726.12.43.6630.23632258060.4032258065
31.32.681026.823.827.53.75.6471250.21071361940.268
31.32.96257423.935.111.217.0940.2310.1184
31.32.85.214.5624.226.72.53.8156250.26206215660.5384615385
31.337.823.424.327.43.14.7313750.20219551280.3846153846
31.33.089.930.49224.328.23.95.9523750.1952110390.3111111111
31.33.314.547.8524.330.25.99.0048750.18818965520.2275862069
31.33.351963.6524.432.58.112.3626250.19422820110.1763157895
31.33.4721.474.25824.434.810.415.8730.2137547470.23266019910.1621495327
20mTorr20.85.79.755.2924.729.95.27.93650.14354313620.587628866
20.85.8105824.730.55.88.852250.1526250.58
20.85.8512.472.5424.832.17.311.1416250.15359284530.4717741935
20.85.981695.6824.834.79.915.1098750.15792093440.37375
20.86.121.4130.5424.83914.221.672750.16602382410.285046729
20.86.2223.5146.172541.416.425.03050.1712423890.15749135480.2646808511
pAVG H/P
16mTorr168.411.294.0825.634.38.713.2783750.14113919010.7531.30.2326601991
168.4113.1110.17125.735.910.215.567750.14130533440.6419847328250.1859116808
168.3515.6130.2625.73812.318.7728750.14411849380.5352564103200.1574913548
17.68.1519.2156.4825.841.215.423.504250.15020609660.4244791667160.1417915626
168.89.886.2426.233.87.611.59950.1345025510.8979591837140.1202911405
8.814.3125.8426.137.611.517.5518750.13947770980.14179156260.6153846154130.1018718839
14mTorr14.58.41.714.2826.327.41.11.6788750.11756827734.9411764706
14.58.6217.226.227.61.42.136750.12422965124.3
14.58.72.723.4926.2281.82.747250.1169540233.2222222222
14.58.783.429.85226.228.52.33.5103750.11759262362.5823529412
14.58.94.540.0526.229.33.14.7313750.11813670411.9777777778
14.595.650.426.130.34.26.410250.12718751.6071428571
14.599.383.726.233.37.110.8363750.12946684590.9677419355
14.58.652.420.7626.527.91.42.136750.10292630063.6041666667
14.58.83.530.826.428.82.43.6630.11892857142.5142857143
14.58.94.640.9426.429.73.35.0366250.12302454811.9347826087
14.596.457.626.531.34.87.3260.12718750.12029114051.40625
13mTorr1310.82.52726.528.31.82.747250.101754.32
10.82.628.0826.428.31.92.8998750.10327190174.1538461538
500mR/h at VP1144426.429.32.94.4261250.100593750.10187188392.75
Sheet1
31mTorr
25mTorr
20mTorr
16mTorr
14.5mTorr
13mTorr
P: Drive Power(W), Ion source on
H: Grid Heating (W)
y(25mTorr) = 0.0721x1.2553R2 = 0.9822
y(20mTorr) = 0.0816x1.1471R2 = 0.9985
y(16mTorr) = 0.1139x1.0468R2 = 0.9984
y(14.5mTorr) = 0.0937x1.0712R2 = 0.9926
Sheet2
31mTorr
25mTorr
20mTorr
16mTorr
14.5mTorr
13mTorr
H: Drive Current(mA), Ion source on
H: Grid Heating (W)
Sheet3
Pressure (mTorr)
Power-Heating Curve Exponent
Average H/P
H/P Exponent
Pressure (mTorr)
H/P: Grid Heating (W) / Drive Power(W)
Power-Heating Curve Exponent
31mTorr
25mTorr
20mTorr
16mTorr
14.5mTorr
13mTorr
Z(MOhm): Drive Voltage(kV) / Drive Current(mA)
H/P: Grid Heating (W) / Drive Power(W)
31mTorr
25mTorr
20mTorr
16mTorr
14.5mTorr
13mTorr
Drive Voltage(kV)
Z(MOhm): Drive Voltage(kV) / Drive Current(mA)
31mTorr
25mTorr
20mTorr
16mTorr
14.5mTorr
13mTorr
P: Drive Power(W)
Z(MOhm): Drive Voltage(kV) / Drive Current(mA)