Merge remote-tracking branch 'ngsolve/main'

README.md

@@ -1,13 +1,35 @@
 # JupyterLite Demo
 
-[![lite-badge](https://jupyterlite.rtfd.io/en/latest/_static/badge.svg)](https://jupyterlite.github.io/demo)
+[![lite-badge](https://jupyterlite.rtfd.io/en/latest/_static/badge.svg)](https://ngsolve.github.io/jupyterlite_ngsolve/lab?path=poisson.ipynb)
 
 JupyterLite deployed as a static site to GitHub Pages, for demo purposes.
 
 ## ✨ Try it in your browser ✨
 
-➡️ **https://mhochsteger.github.io/jupyterlite_ngsolve**
+➡️ **https://ngsolve.github.io/jupyterlite_ngsolve/lab?path=poisson.ipynb**
 
-![github-pages](https://user-images.githubusercontent.com/591645/120649478-18258400-c47d-11eb-80e5-185e52ff2702.gif)
 
+## Setting up your own NGSolve - jupyterlite demos:
 
+1. Sign in to your github account
+
+2. Click on 'Use this template' to create your new, public repository
+
+3. Enable 'github-pages from actions':
+
+   Settings -> Pages -> Source: 'github actions'
+
+4. Click on 'Actions', and allow workflow actions (maybe not necessary ?)
+
+5. Fill the 'contents' folder with your notebooks
+
+6. Adjust links to your github pages website
+
+
+
+## Further Information and Updates
+
+For more info, keep an eye on the JupyterLite documentation:
+
+- How-to Guides: https://jupyterlite.readthedocs.io/en/latest/howto/index.html
+- Reference: https://jupyterlite.readthedocs.io/en/latest/reference/index.html

content/elasticity3D.ipynb

@@ -0,0 +1,261 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "id": "2f25f55f",
+   "metadata": {},
+   "source": [
+    "# 3D Solid Mechanics"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "2ad7a13b",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "from netgen.occ import *\n",
+    "from netgen.webgui import Draw as DrawGeo\n",
+    "import ngsolve"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "cf326b31",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "box = Box((0,0,0), (3,0.6,1))\n",
+    "box.faces.name=\"outer\"\n",
+    "cyl = sum( [Cylinder((0.5+i,0,0.5), Y, 0.25,0.8) for i in range(3)] )\n",
+    "cyl.faces.name=\"cyl\"\n",
+    "geo = box-cyl\n",
+    "\n",
+    "DrawGeo(geo);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "d54d7749",
+   "metadata": {},
+   "source": [
+    "find edges between box and cylinder, and build chamfers (requires OCC 7.4 or newer):"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "96197254",
+   "metadata": {
+    "tags": [
+     "raises-exception"
+    ]
+   },
+   "outputs": [],
+   "source": [
+    "cylboxedges = geo.faces[\"outer\"].edges * geo.faces[\"cyl\"].edges\n",
+    "cylboxedges.name = \"cylbox\"\n",
+    "geo = geo.MakeChamfer(cylboxedges, 0.03)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "8f356223",
+   "metadata": {},
+   "source": [
+    "name faces for boundary conditions:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "8701d6a2",
+   "metadata": {
+    "scrolled": false
+   },
+   "outputs": [],
+   "source": [
+    "geo.faces.Min(X).name = \"fix\"\n",
+    "geo.faces.Max(X).name = \"force\"\n",
+    "\n",
+    "DrawGeo(geo);"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "93554691",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "from ngsolve import *\n",
+    "from ngsolve.webgui import Draw\n",
+    "mesh = Mesh(OCCGeometry(geo).GenerateMesh(maxh=0.1)).Curve(3)\n",
+    "Draw (mesh);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "7d07fa0a",
+   "metadata": {},
+   "source": [
+    "## Linear elasticity\n",
+    "\n",
+    "Displacement: $u : \\Omega \\rightarrow R^3$\n",
+    "\n",
+    "Linear strain:\n",
+    "$$\n",
+    "\\varepsilon(u) := \\tfrac{1}{2} ( \\nabla u + (\\nabla u)^T )\n",
+    "$$\n",
+    "\n",
+    "Stress by Hooke's law:\n",
+    "$$\n",
+    "\\sigma = 2 \\mu \\varepsilon + \\lambda \\operatorname{tr} \\varepsilon I\n",
+    "$$\n",
+    "\n",
+    "Equilibrium of forces:\n",
+    "$$\n",
+    "\\operatorname{div} \\sigma = f\n",
+    "$$\n",
+    "\n",
+    "Displacement boundary conditions:\n",
+    "$$\n",
+    "u = u_D \\qquad \\text{on} \\, \\Gamma_D\n",
+    "$$\n",
+    "\n",
+    "Traction boundary conditions:\n",
+    "$$\n",
+    "\\sigma n = g \\qquad \\text{on} \\, \\Gamma_N\n",
+    "$$\n",
+    "\n",
+    "\n",
+    "Variational formulation:\n",
+    "--- \n",
+    "Find: $u \\in H^1(\\Omega)^3$ such that $u = u_D$ on $\\Gamma_D$\n",
+    "$$\n",
+    "\\int_\\Omega \\sigma(\\varepsilon(u)) : \\varepsilon(v) \\, dx = \\int_\\Omega f v dx + \\int_{\\Gamma_N} g v ds\n",
+    "$$\n",
+    "holds for all $v = 0$ on $\\Gamma_D$."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "957549ab",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "E, nu = 210, 0.2\n",
+    "mu  = E / 2 / (1+nu)\n",
+    "lam = E * nu / ((1+nu)*(1-2*nu))\n",
+    "\n",
+    "def Stress(strain):\n",
+    "    return 2*mu*strain + lam*Trace(strain)*Id(3)    "
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "00178f2a",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "fes = VectorH1(mesh, order=3, dirichlet=\"fix\")\n",
+    "u,v = fes.TnT()\n",
+    "gfu = GridFunction(fes)\n",
+    "\n",
+    "with TaskManager():\n",
+    "    a = BilinearForm(InnerProduct(Stress(Sym(Grad(u))), Sym(Grad(v))).Compile()*dx)\n",
+    "    pre = Preconditioner(a, \"bddc\")\n",
+    "    a.Assemble()"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "54b8ead2",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "force = CF( (1e-3,0,0) )\n",
+    "f = LinearForm(force*v*ds(\"force\")).Assemble()"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "4e0ec2a2",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "from ngsolve.krylovspace import CGSolver\n",
+    "inv = CGSolver(a.mat, pre, printrates='\\r', tol=1e-8)\n",
+    "gfu.vec.data = inv * f.vec"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "c0845659",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "with TaskManager():\n",
+    "    fesstress = MatrixValued(H1(mesh,order=3), symmetric=True)\n",
+    "    gfstress = GridFunction(fesstress)\n",
+    "    gfstress.Interpolate (Stress(Sym(Grad(gfu))))"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "c889b0da",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "Draw (5e4*gfu, mesh);"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "c49a4f27",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "Draw (Norm(gfstress), mesh, deformation=1e4*gfu, draw_vol=False, order=3);"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "876acb13",
+   "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": "3.11.5"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 5
+}