Adding COMSOL test example

doc/coupling_to_plasma_from_COMSOL.ipynb

@@ -0,0 +1,274 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Plasma Coupling Using COMSOL Results"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "In this example, we use a COMSOL front-face coupling calculation provided by ORNL, exported as a standard Touchstone file.\n",
+    "\n",
+    "The Touchstone file is first import as a scikit-rf Network, which is then modified to fit the WEST ICRH antenna electrical model requirements."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 25,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "import numpy as np\n",
+    "import skrf as rf\n",
+    "\n",
+    "# WEST ICRH Antenna package\n",
+    "import sys; sys.path.append('..')\n",
+    "from west_ic_antenna import WestIcrhAntenna"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 26,
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "4-Port Network: 'ORNL_front_face_conventional',  55000000.0-55000000.0 Hz, 1 pts, z0=[50.+0.j 50.+0.j 50.+0.j 50.+0.j]\n"
+     ]
+    }
+   ],
+   "source": [
+    "front_face_conventional = rf.Network(\n",
+    "    '../west_ic_antenna/data/Sparameters/front_faces/COMSOL/ORNL_front_face_conventional.s4p')\n",
+    "print(front_face_conventional)  # 50 Ohm S-param component at a single frequency of 55 MHz"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "The ports have been defined as:\n",
+    "<img src=\"COMSOL_WEST_port_index.png\" />\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "So before to use the S-parameters directly to feed the electrical model, we need to:\n",
+    "- deembed the ports by 0.3m.\n",
+    "- renomalize port reference impedance to the front-face coax characteristic impedances. \n",
+    "- reverse ports 2 and 3."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 27,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "# creating a 50 Ohm dummy coax line to be removed from the front face \n",
+    "media_coax = rf.DefinedGammaZ0(frequency=front_face_conventional.frequency) # 50 Ohm TEM media\n",
+    "extra_line = media_coax.line(d=0.3, unit='m')\n",
+    "# deembedding all the 4 pourts\n",
+    "for port_idx in range(4):\n",
+    "    front_face_conventional = rf.connect(front_face_conventional, port_idx, extra_line.inv, 0)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "We expect the port to have a characteristic impedance of about 46.64 ohm, so we renormalize the Network to fit this need:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 28,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "front_face_conventional.renormalize(46.64)  # done inplace"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "And finally, for historical reasons (may change in a near future ;), the S-matrix port ordering should be ajusted:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 29,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "front_face_conventional.renumber([1, 2], [2, 1]) # done inplace"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "OK, so now we can create the WEST antenna object:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 30,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "ant = WestIcrhAntenna(front_face=front_face_conventional,\n",
+    "                     frequency=front_face_conventional.frequency) # restrict to single frequ"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "Let's match the antenna for this coupling:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 31,
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Looking for individual solutions separately for 1st guess...\n",
+      "Wrong solution (out of range capacitor) ! Re-doing...\n",
+      "False solution #1: [150. 150.]\n",
+      "True solution #1: [52.57986227 45.88696785]\n",
+      "True solution #1: [52.30894839 46.0700872 ]\n",
+      "Searching for the active match point solution...\n",
+      "Reducing search range to +/- 5pF around individual solutions\n",
+      "True solution #1: [53.67807308 46.12207788 53.62800637 46.30935881]\n"
+     ]
+    }
+   ],
+   "source": [
+    "Cs = ant.match_both_sides(f_match=55e6)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "The coupling resistance of the antenna for this coupling in a nominal dipole excitation is:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 32,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "array([0.70081638, 0.6878438 ])"
+      ]
+     },
+     "execution_count": 32,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "power = [1, 1]\n",
+    "phase = [0, np.pi]\n",
+    "\n",
+    "# Coupling resistance\n",
+    "ant.Rc(power, phase)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "The voltage and currents are:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 44,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "array([[22.16126386, 23.75535708, 20.56902439, 25.21223565]])"
+      ]
+     },
+     "execution_count": 44,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "power = [1, 1]  # MW, to adjust to fit with experiment\n",
+    "phase = [0, np.pi]  # rad\n",
+    "\n",
+    "abs(ant.voltages(power, phase))  # results in kV"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 41,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "array([[0.70248687, 0.75556107, 0.65298786, 0.80405425]])"
+      ]
+     },
+     "execution_count": 41,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "abs(ant.currents(power, phase))  # results in kA"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": []
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3 (ipykernel)",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.11.7"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 4
+}

west_ic_antenna/data/Sparameters/front_faces/COMSOL/ORNL_front_face_conventional.s4p

@@ -0,0 +1,5 @@
+# Hz S MA R 50
+5.5E7 0.9833673750492276 80.96377443955839 0.008159649655058979 7.738772614443071 0.0145413437349296 16.766538738668693 0.0010505712330604862 -169.75560162791115
+      0.005398399959278055 22.968885177373394 0.9848074824065548 80.65809524512109 0.002317451028156058 3.2454593187084524 0.013899534074545427 14.553096258345233
+      0.015466057366109193 15.352573092351177 0.0017852444452037635 2.802734655640837 0.9830347719457835 80.74299676938419 0.00812386410086659 7.621156795969611
+      0.0010813303292888372 -61.44581050964589 0.014724345533904457 13.318047129975318 0.005359073489960678 22.934149123418244 0.9850374253641254 80.8905612330192

west_ic_antenna/data/Sparameters/front_faces/COMSOL/ORNL_front_face_plasma_inside.s4p

@@ -0,0 +1,5 @@
+# Hz S MA R 50
+5.5E7 0.9531014698199719 74.68128260423282 0.011727825824109023 22.140672391691247 0.0042213470494665405 11.518713731671811 0.002189631421892682 42.58156998869071
+      9.251508660246946E-4 -70.21624695384136 0.958437677141582 73.97406838963975 1.7232083904810094E-4 -60.95155708607013 0.005781121306569129 11.04470231400275
+      0.003550071050919271 -5.440992958402874 0.0031673180639685814 30.852889750516837 0.9523110682604861 74.3856493165878 0.011744626700427849 22.11148013138784
+      1.7657833450556378E-4 -67.23316376248191 0.005247609440270916 0.5440706526584136 9.356608093953542E-4 -69.87439488938504 0.9590992784229622 74.23536526952307