DE-R Four Module + E-beam simulation
!
! Rick Spielman 2018-06-18
!
Time-step 2.0e-12
Resolution-time 100e-12
End-time 1.0e-6
Number-prints 5
Execute-cycles all
Grids no
Echo-setup no
Detail-prints full
Max-points 5001
!
!Start circuit definition
!
! DE-R_rev6a.txt is based on DE-R_rev6.txt with the branch removed and an electron beam
! diode added
!
! DE-R_rev6.txt is based on DE-R_rev5final.txt but we are changing the sub-Marxes to 20 stages
! and charging to 85 kV.
!
! DE-R_rev5final.txt is based on DE-R_rev5b.txt but the water line details are
! changed to reflect the final value of the conceptual design. Also adding a length scaling factor
! to correct for the overestimate of the water switch resistance of 40%. Decrease length by .4.
!
! DE-R_rev5b.txt is based on DE-R_rev5a.txt. In this run deck we are splitting the two halves
! of the water lines AND Marxes in half so that we can drive each side of the vacuum disk feed 
! separately. This allows more accurate treatment of the individual MITLs and the convolute.
!  MITL and Z_flow models will be incorporated into the deck. We will divide C by 2X and multiply L
! and R by 2X. Remember that the IOUT/IIN calls are backward in the second branch.
! In this run each Marx has a capacitance of 70.5 nF and the L1 with ~ 42.85 nF
!
! DE-R Rev5a.txt is based on DE-R Rev4a.txt. We are including a PRS load using the general 
!  parameters of the Z51 deck used in Z15_rev2_Z51.txt. The exact inductance numbers have
!  been tweaked a bit to be self consistent. We output V, I before the MITL TR and V,I after the MITL.
!
! DE-R Rev4a is based on DE-R Rev4. I am removing all of the extra branches to speed iteration. 
! This forces me to divide all marx and water line impedances and inductances by four
! and to increase the Marx C by 4.
!
! DE-R Rev 3a is based on DE-R Rev 2a. We are lowering the WL impedance to 0.4 Ω (1.6/4) and
! explicitly putting in the water flare impedance of the stack. In addition, the insulator, vacuum flare, 
! and MITL impedances will be rechecked. Goal - explicit identification of all impedance and 
! inductance components.
!
! DE-R Rev 2a uses the DE-R Rev 2 deck with 4 parallel modules that are driving an insulator stack,
! MITL, and e-beam load. We will use 4, separate modules joined to the insulator stack with
! End Branches. This way we can keep the Rev1b structure exactly. We also allow jitter in the 
! Future. Note: the module end branches are in reverse order away from the branch.
!
! DE-R Rev 1 uses the DE Rev 4 as the baseline. We will be changing all the line impedances to
! 2 Ω and will be changing the line lengths. The goal here is to have a driver that delivers a clean 100-ns FWHM pulse to a constant impedance load.
!
! Rev 4 changes the CPL water switch gap to the actual gap 3.75”
! also changes the output line to constant 1.3 Ω impedance with a matched load.
!
! Rev 3 Marx switch losses and more accurate water line parameters
! Change marx to 30 stages of 300 nF/stage
!
! Gas switch dimensions from drawings
!
! The sub Marx capacitance is 290 nF/40= 7.25 nF. We operate at a charge voltage of 85 kV.
! We have a 7.25-nF sub Marx with 40 cap pairs in series and 20 switches. Vch = 3.4 MV
! We have 8 sub Marxes in parallel per module.
! The total Marx module capacitance is 58 nF.
!
! Include 130 mΩ individual cap ESR or 65 mΩ per pair of caps in parallel in a half stage
!   X 20 stages per sub-Marx = 2.6 Ω per sub-Marx
!
! With 167 nH every stage. L = 167 nH * 20 = 3.34 µH.
! The total Marx module inductance (caps and switches) would be 3.34 µH/8 = 417 nH
!
! The total Marx capacitance is 58 nF. This implies
!   that there will a ringing gain on the CPL. This allows a faster rise time than otherwise to 
!   get to the desired CPL voltage.
!
! CPL capacitance used is 42.85 nF. This is distributed in a TL that is ~60 ns long and
!   has a constant impedance of 1.4 Ω. (C = t/Z = 60/1.4 nF = 42.85 nF) 
!  Optimum C ratio is 1.5X to Cmarx = 64.275 nF (we are a bit low in the Marx but OK)
!
! Energy per Marx module at 85 kV = 335.2 kJ, 2 marxes = 670.5 kJ, 4 marxes = 1.34 MJ
!
! The matched impedance of a sub-Marx = sqrt(L/C) = 21.46 Ω.
!   The total Marx impedance is 21.46 Ω/8 = 2.68 Ω
!   Note CPL impedance is 1.4 Ω.
!   The ESR amounts to ~ 12.1% of the matched impedance.
!
! The switch model will have 20x the length of one switch per sub Marx and then will
! have 8 arc channels (sub Marxes) in parallel.
! Then there will be two Marxes in parallel representing half of the machine
! 
! We will assume a TOTAL inductance of 417 + 100 = 517 nH for one Marx and one L1.
! The total inductance for Branch A (and also Branch B) two modules in parallel is 258.5 nH.
!
! 
! Main Branch - Branch #1
!
BRANCH
!
! B LEVEL
!
! Marx capacitance and charge voltage
! CX2 for two modules (58 nF each Marx module) = 116 nF
! +/-85 kV charge x 40 = 3.4 MV
!
RCGround 1e+12 116e-9
Initial VC1 3.4e6

TXT VC1 SCAle 1.0e-06
$V_marx_B (MV)
TXT EC1 SCAle 1.0e-03
$E_marx_B (kJ)

!
! Cap inductance, case & parasitic inductance, and ESR
! ESR = 0.325 for the total Marx module (2.6 Ω sub Marx/8)
! Inductance is 417 nH per module 
! Divide R and L by 2 for 2 modules (driving one MITL)
!

RLSeries 0.1625 208.5e-9

!
! Switch resistance - Martin Model and switch inductance - the total gap for a single
! switch from DWGs is 0.53” (1.346 cm) gap and 93 psig air X 20 = 26.92 cm
!
! Initial switch resistance was chosen to be higher than that printed in the first
! few time steps so as to appear monotonically decreasing in R plots
! A careful few runs showed that 10 GΩ looked best. In any event by 1 ns all of the 
! resistance values are the same.
!  20 switches for 8 sub-Marxes, 2 channels for 2 modules
!  Divide parallel switch inductance for one Marx (~50 nH) by 2 for 2 modules
! Not right - switch inductance is already included in inductance above.
!

RLSeries 10e9 25e-9
Var R2 Switch
!dielectric switchtime gap        pressure     nswitch  nchannels
AIR           0.0               0.2692  7.3                8             2

TXT IR2 SCAle 1.0e-06
$I_marx_B (MA)
TXT R2
$R_switch_B (Ohm)
TXT ER2 SCAle 1.0e-03
$E_switch_B (kJ)
TXT QR2
$Q_switch_B (C)

!
! Output Marx header inductance
! Divide 100 nH per interface by 2 for 2 Marxes in parallel per module
! QE will have two modules per level (divide inductance by 2) 
!

RLSeries 0.00 25e-9

!
! Line 1 (CPL), 60 ns, 1.4 Ω, 60 ns/1.4= 42.85 nF per L1
! Divide Z by 2 for one half of DE-R driving one insulator stack
! Include the radius transition of the L1 
!

TRLine EXP 2.29e-09  2  .7
TRLine LIN 56.0e-09   .7 .7
TRLine EXP 2.29e-09 .7  2

TXT VOUT SCAle 1.0e-06
$V_L1_out_B (MV)
TXT IOUT SCAle 1.0e-06
$I_L1_out_B (MA)
TXT EOUT SCAle 1.0e-03
$E_L1_out_B (kJ)
TXT POUT SCAle 1.0e-12
$P_L1_out_B (TW)

!
! Line 1 water switches - gap is scaled by 0.6
! 5 output switches, 4” gap x .6 = 2.4"  (DE today) + switch inductance
!  Increase number of channels x2 for the two modules
!

RLSeries 10e9 5e-9
Var R2 Switch
!dielectric switchtime gap         pressure   nswitch  nchannels
H2O          310e-09     0.06096   1.0              5             2

TXT IR2 SCAle 1.0e-06
$I_L1_sw_B (MA)
TXT R2
$R_L1_sw_B (Ohm)
TXT ER2 SCAle 1.0e-03
$E_L1_sw_B (kJ)
TXT QR2
$Q_L1_sw_B (C)

!
! Line 2, 72 ns, 1.4 Ω constant impedance
! Divide by 2 for 2 modules
!

TRLine EXP 2.29e-09 2 .7

TXT VIN SCAle 1.0e-06
$V_PFL_in_B (MV)
TXT IIN SCAle 1.0e-06
$I_PFL_in_B (MA)

TRLine LIN 68e-09      .7 .7
TRLine EXP 2.29e-09 .7 2

TXT VOUT SCAle 1.0e-06
$V_PFL_out_B (MV)
TXT IOUT SCAle 1.0e-06
$I_PFL_out_B (MA)
TXT POUT SCAle 1.0e-12
$P_PFL_out_B (TW)
TXT EOUT SCAle 1.0e-03
$E_PFL_out_B (kJ)

!
! Line 2 water switches - gap is scaled by 0.6
! 7 output switches, 0.5" x .6 = 0.3” gap + switch inductance
! Increase number of channels to two for two modules
!

RLSeries 10e9 5e-9
Var R2 Switch
!dielectric switchtime gap      pressure     nswitch  nchannels
H2O         385e-09    0.00762   1.0                    7               2

TXT IR2 SCAle 1.0e-06
$I_PFL_sw_B (MA)
TXT R2
$R_PFL_sw_B (Ohm)
TXT ER2 SCAle 1.0e-03
$E_PFL_sw_B (kJ)

!
! Output Line (OL),  72 ns, 1.4 Ω constant impedance
!  Divide Z by 2 for two modules
!

TRLine EXP 2.29e-09 2 .7

TXT VIN SCAle 1.0e-06
$V_OL_in_B (MV)
TXT IIN SCAle 1.0e-06
$I_OL_in_B (MA)

TRLine LIN 70e-09 .7 .7

TXT VOUT SCAle 1.0e-06
$V_OL_out_B (MV)
TXT IOUT SCAle 1.0e-06
$I_OL_out_B (MA)
TXT POUT SCAle 1.0e-12
$P_OL_out_B (TW)
TXT EOUT SCAle 1.0e-03
$E_OL_out_B (kJ)

!
!  ********* Water flare transition external to the insulator stack ****************
!  Router = 1.165 m , stack outer = 1.1 m, constant 13.35-cm gap, l = 1.96 ns
!  —— Divide by 2X for half QE Zouter = 0.76 Ω, Zinner = 0.81 Ω
!

TRLine LIN 1.96e-9 0.76 0.81

!
!   ***********************  Insulator stack  *****************************
! The water/vacuum interface Router=1.1 m, Rinner=1.0 m, height=13.35 cm (0.64-cm grading rings) 
!  Plastic height is 11.43 cm. L per side = 2.1788 nH
!

RLSeries  0.0    2.1788E-9

!
TXT VOUT SCAle 1.0e-06
$V_stack_B (MV)
TXT IOUT SCAle 1.0e-06
$I_stack_B (MV)
TXT POUT SCAle 1.0e-12
$P_stack_B (TW)
TXT EOUT SCAle 1.0e-03
$E_stack_B (kJ)

!
!   **************************  First vacuum piece inside insulator  *****************************
!  Constant 13.35 cm height, Router = 1 m, Rinner = 0.975 m
! Inductance = 0.676 nH
!

RLSeries  0.0    0.676E-9

!
!
!   **************************  Vacuum flares  *****************************
! The flare includes the flare itself and the rectangular piece that extends down to the cathode.
! L1=0.639 nH, L2=0.924 nH, L1+L2=1.563 nH
! This section would be better modeled as MITLs as the lower portion of the feed could be 
!  emissive.
!

RLSeries  0.0    1.563E-9

!
! Extra stray L in the flare region 0.5 nH, just a WAG
!

RLSeries  0.0    0.5E-9

!
TXT VOUT SCAle 1.0e-06
$V_vf_B (MV)
TXT IOUT SCAle 1.0e-06
$I_vf_B (MA)
TXT POUT SCAle 1.0e-12
$P_vf_B (TW)
TXT EOUT SCAle 1.0e-03
$E_vf_B (kJ)

!
!   *****************************   Constant Z MITLs   ********************************
! Z= 3.7 Ω, length = 2.45 ns (Router = 89.65 cm gap=5.53 cm, Rinner=16.2 cm gap=1 cm)
! L=Zt - 9.25 nH
! I will divide the spacing between Router and Rinner into 10 segments of equal distance
!  and use the mid point of each segment as the circumference for the MITL model.
! 7.345 cm long segments, length (ns) - 
! MITL midpoints (cm) - 85.98, 78.63, 71.29, 63.94, 56.60, 49.25, 41.91, 34.56, 27.22, 19.87
! circumferences (m) - 5.40, 4.94, 4.48, 4.017, 3.556, 3.094, 2.633, 2.171, 1.71, 1.248
! vac gap for 3.7 Ω (m) - 5.306e-2, 4.852e-2, 4.4e-2, 3.946e-2, 3.492e-2, 3.039e-2, 2.586e-2, 2.133e-2, 1.68e-2, 1.226e-2
!
!MITL      Circum            Gap            Length-s       Impedance        Resolution       E-Turnon
MITL         5.40            5.306e-02     0.245E-09          3.7                      0.05e-9

TXT VOUT SCAle 1.0e-06
$V_mitl1_out_B (MV)
TXT IOUT SCAle 1.0e-06
$I_mitl1_out_B (MA)
TXT CLOS
$I_mitl1_loss_B (A)
TXT ALOS
$J_mitl1_loss_B (A/m2)

!MZFlow 3.7
!TXT ICA
!$Icath_mitl1_B
!TXT IPL
!$Iflow_mitl1_B
!TXT ZOT
!$Zflow_mitl1_B
               
MITL         4.94          4.852e-02        0.245E-09          3.7                      0.05e-9               

TXT VOUT SCAle 1.0e-06
$V_mitl2_out_B (MV)
TXT IOUT SCAle 1.0e-06
$I_mitl2_out_B (MA)
TXT CLOS
$I_mitl2_loss_B (A)
TXT ALOS
$J_mitl2_loss_B (A/m2)

MITL         4.48          4.4e-02        0.245E-09          3.7                      0.05e-9               

TXT VOUT SCAle 1.0e-06
$V_mitl3_out_B (MV)
TXT IOUT SCAle 1.0e-06
$I_mitl3_out_B (MA)
TXT CLOS
$I_mitl3_loss_B (A)
TXT ALOS
$J_mitl3_loss_B (A/m2)

MITL         4.017        3.946e-02       0.245E-09          3.7                      0.05e-9               

TXT VOUT SCAle 1.0e-06
$V_mitl4_out_B (MV)
TXT IOUT SCAle 1.0e-06
$I_mitl4_out_B (MA)
TXT CLOS
$I_mitl4_loss_B (A)
TXT ALOS
$J_mitl4_loss_B (A/m2)

MITL         3.556         3.492e-02        0.245E-09          3.7                      0.05e-9

TXT VOUT SCAle 1.0e-06
$V_mitl5_out_B (MV)
TXT IOUT SCAle 1.0e-06
$I_mitl5_out_B (MA)
TXT CLOS
$I_mitl5_loss_B (A)
TXT ALOS
$J_mitl5_loss_B (A/m2)

MITL         3.094         3.039e-02        0.245E-09          3.7                      0.05e-9

TXT VOUT SCAle 1.0e-06
$V_mitl6_out_B (MV)
TXT IOUT SCAle 1.0e-06
$I_mitl6_out_B (MA)
TXT CLOS
$I_mitl6_loss_B (A)
TXT ALOS
$J_mitl6_loss_B (A/m2)

MITL         2.633         2.586e-02        0.245E-09          3.7                      0.05e-9

TXT VOUT SCAle 1.0e-06
$V_mitl7_out_B (MV)
TXT IOUT SCAle 1.0e-06
$I_mitl7_out_B (MA)
TXT CLOS
$I_mitl7_loss_B (A)
TXT ALOS
$J_mitl7_loss_B (A/m2)

MITL        2.171         2.133e-02        0.245E-09          3.7                      0.05e-9

TXT VOUT SCAle 1.0e-06
$V_mitl8_out_B (MV)
TXT IOUT SCAle 1.0e-06
$I_mitl8_out_B (MA)
TXT CLOS
$I_mitl8_loss_B (A)
TXT ALOS
$J_mitl8_loss_B (A/m2)

MITL         1.71         1.678e-02        0.245E-09          3.7                      0.05e-9

TXT VOUT SCAle 1.0e-06
$V_mitl9_out_B (MV)
TXT IOUT SCAle 1.0e-06
$I_mitl9_out_B (MA)
TXT CLOS
$I_mitl9_loss_B (A)
TXT ALOS
$J_mitl9_loss_B (A/m2)

MITL         1.248         1.226e-02        0.245E-09          3.7                      0.05e-9

TXT VOUT SCAle 1.0e-06
$V_mitl10_out_B (MV)
TXT IOUT SCAle 1.0e-06
$I_mitl10_out_B (MA)
TXT CLOS
$I_mitl10_loss_B (A)
TXT ALOS
$J_mitl10_loss_B (A/m2)
TXT POUT SCAle 1.0e-12
$P_mitl10_out_B (TW)
TXT EOUT SCAle 1.0e-03
$E_mitl10_out_B (kJ)

!
! Inductance of the disk MITL - disk plate, 16.2 cm to 15.2 cm (6")
!    Gap = 1 cm at this location, top and bottom 0.127 nH
!    Will need MITL calls here at some point.
!

!RLSeries 0.0       0.127E-9

!
!   *******************  Coax MITL  ********************
!  Cathode radius 15.2 cm, anode radius 16.2 cm, cath circ = 95.5 cm
!

!MITL      Circum            Gap            Length-s       Impedance       (Resolution)      (E-Turnon)
MITL         0.955            1.0e-02       0.25E-09          3.7                     0.05e-9

TXT VOUT SCAle 1.0e-6
$V_mitlc_out_B (MV)
TXT IOUT SCAle 1.0e-6
$I_mitlc_out_B (MA)
TXT CLOS
$I_mitlc_loss_B (A)
TXT ALOS
$J_mitlc_loss_B (A/m2)

!
! L in the diode gap volume
! Ro=16.2, Rin=15.2, h = diode gap (10mm-0.127 nH, 6.5mm-0.082 nH)
!

RLSeries  0.0      0.127E-9

!     
!    *********   Electron Beam Diode   ****************************
!

RCGround 1e6 0.0
VARiable R1 EDIode
!Diode_type Gap       Enhancement   Velocity     Router     (Rinner)
3                     0.8e-2      3.0                   1.0e4         15.2e-2    14.2e-2
!
TXT R1
$Z_diode (Ohm)
TXT IR1 SCAle 1.0e-6
$I_diode (MA)
TXT VR1 SCAle 1.0e-6
$V_diode (MV)
TXT PR1 SCAle 1.0e-12
$P_diode (TW)
TXT ER1 SCAle 1.0e-3
$E_diode (kJ)

!
! End Main Branch (Branch #1)
!