cleanup volume-to-mass refactor leftover

examples/PySDM_examples/Arabas_et_al_2023/fig_A2.ipynb

@@ -76,7 +76,7 @@
     "cases = tuple({\"dt\": dt, \"N\": mlt, \"seed\": seed} for dt, mlt, seed in itertools.product(DTS, MLT, SEEDS))\n",
     "\n",
     "# dummy (but must-be-set) values\n",
-    "vol = 44  # for sign flip (ice water has negative volumes), value does not matter\n",
+    "mass = 44  # for sign flip (ice water has negative mass), value does not matter\n",
     "d_v = 666  # products use conc., dividing there, multiplying here, value does not matter\n",
     "\n",
     "output = {}\n",
@@ -110,7 +110,7 @@
     "        attributes = {\n",
     "            \"multiplicity\": np.full(n_sd, int(case[\"N\"])),\n",
     "            \"immersed surface area\": np.full(n_sd, immersed_surface_area),\n",
-    "            \"volume\": np.full(n_sd, vol),\n",
+    "            \"water_mass\": np.full(n_sd, mass),\n",
     "        }\n",
     "        particulator = builder.build(attributes=attributes, products=products)\n",
     "        env[\"RH\"] = 1.0001\n",
@@ -123,7 +123,7 @@
     "\n",
     "            ice_mass_per_volume = particulator.products[\"qi\"].get()[cell_id]\n",
     "            ice_mass = ice_mass_per_volume * d_v\n",
-    "            ice_number = ice_mass / (const.rho_w * vol)\n",
+    "            ice_number = ice_mass / mass\n",
     "            unfrozen_fraction = 1 - ice_number / number_of_real_droplets\n",
     "            output[backend_key][key][\"unfrozen_fraction\"].append(unfrozen_fraction)\n",
     "        \n",