Add lidDrivenCavity2DCreepingFlow node.js example

nikoscham · nikoscham · commit 00da9385a3b7 · 2026-02-16T10:55:59.000+02:00
diff --git a/examples/creepingFlowScript/README.md b/examples/creepingFlowScript/README.md
@@ -0,0 +1,34 @@
+<img src="https://feascript.github.io/FEAScript-website/assets/feascript-creeping-flow.png" width="80" 
+alt="FEAScript creepingFlow Logo">
+
+# Creeping Flow Examples
+
+This directory contains Node.js examples demonstrating how to use the FEAScript library to solve steady creeping flow (Stokes) problems.
+
+## Examples
+
+#### 1. Lid-Driven Cavity (2D Creeping Flow) (`lidDrivenCavity2DCreepingFlow.js`)
+
+This example solves a 2D lid-driven cavity flow using the creeping flow solver with Taylor-Hood (Q2-Q1) elements. For detailed information on the model setup, refer to the corresponding [tutorial](https://feascript.com/tutorials/lid-driven-cavity-2d-creeping-flow.html) on the FEAScript website.
+
+## Running the Examples
+
+#### 1. Create package.json with ES module support:
+
+```bash
+echo '{"type":"module"}' > package.json
+```
+
+#### 2. Install dependencies:
+
+```bash
+npm install feascript mathjs
+```
+
+#### 3. Run the example:
+
+```bash
+node lidDrivenCavity2DCreepingFlow.js
+```
+
+(for the "Lid-Driven Cavity (2D Creeping Flow)" example)
diff --git a/examples/creepingFlowScript/lidDrivenCavity2DCreepingFlow/lidDrivenCavity2DCreepingFlow.js b/examples/creepingFlowScript/lidDrivenCavity2DCreepingFlow/lidDrivenCavity2DCreepingFlow.js
@@ -0,0 +1,50 @@
+/**
+ * ════════════════════════════════════════════════════════════════
+ *  FEAScript Core Library
+ *  Lightweight Finite Element Simulation in JavaScript
+ *  Version: 0.2.0 | https://feascript.com
+ *  MIT License © 2023–2026 FEAScript
+ * ════════════════════════════════════════════════════════════════
+ */
+
+// Import Math.js
+import * as math from "mathjs";
+global.math = math;
+
+// Import FEAScript library
+import { FEAScriptModel, printVersion } from "feascript";
+
+console.log("FEAScript Version:", printVersion);
+
+// Create a new FEAScript model
+const model = new FEAScriptModel();
+
+// Select physics/PDE
+model.setModelConfig("creepingFlowScript");
+
+// Define mesh configuration
+model.setMeshConfig({
+  meshDimension: "2D",
+  elementOrder: "quadratic",
+  numElementsX: 12,
+  numElementsY: 6,
+  maxX: 4,
+  maxY: 2,
+});
+
+// Define boundary conditions
+model.addBoundaryCondition("0", ["constantVelocity", 0, 0]); // Bottom boundary
+model.addBoundaryCondition("1", ["constantVelocity", 0, 0]); // Left boundary
+model.addBoundaryCondition("2", ["constantVelocity", 1, 0]); // Top boundary
+model.addBoundaryCondition("3", ["constantVelocity", 0, 0]); // Right boundary
+
+// Set solver method (optional)
+model.setSolverMethod("lusolve");
+
+// Solve the problem
+const { solutionVector, nodesCoordinates } = model.solve();
+
+// Print results
+console.log(`Number of nodes in mesh: ${nodesCoordinates.nodesXCoordinates.length}`);
+console.log("Node coordinates:", nodesCoordinates);
+console.log("Solution vector:", solutionVector);
diff --git a/examples/frontPropagationScript/README.md b/examples/frontPropagationScript/README.md
@@ -1,4 +1,4 @@
-<img src="https://feascript.github.io/FEAScript-website/assets/feascript-front-propagation.png" width="80" alt="FEAScript Logo">
+<img src="https://feascript.github.io/FEAScript-website/assets/feascript-front-propagation.png" width="80" alt="FEAScript frontPropagation Logo">
 
 # Front Propagation Examples
 
diff --git a/examples/frontPropagationScript/solidificationFront2D/solidificationFront2D.js b/examples/frontPropagationScript/solidificationFront2D/solidificationFront2D.js
@@ -33,10 +33,10 @@ model.setMeshConfig({
 });
 
 // Define boundary conditions
-model.addBoundaryCondition("0", ["constantValue", 0]); // Bottom
-model.addBoundaryCondition("1", ["constantValue", 0]); // Left
-model.addBoundaryCondition("2", ["zeroGradient"]); // Top
-model.addBoundaryCondition("3", ["constantValue", 0]); // Right
+model.addBoundaryCondition("0", ["constantValue", 0]); // Bottom boundary
+model.addBoundaryCondition("1", ["constantValue", 0]); // Left boundary
+model.addBoundaryCondition("2", ["zeroGradient"]); // Top boundary
+model.addBoundaryCondition("3", ["constantValue", 0]); // Right boundary
 
 // Set solver method (optional)
 model.setSolverMethod("lusolve");
diff --git a/examples/generalFormPDEScript/README.md b/examples/generalFormPDEScript/README.md
@@ -1,4 +1,4 @@
-<img src="https://feascript.github.io/FEAScript-website/assets/feascript-general-form-pde.png" width="80" alt="FEAScript Logo">
+<img src="https://feascript.github.io/FEAScript-website/assets/feascript-general-form-pde.png" width="80" alt="FEAScript generalFormPDE Logo">
 
 # General Form PDE Examples
 
diff --git a/examples/generalFormPDEScript/advectionDiffusion1D/advectionDiffusion1D.js b/examples/generalFormPDEScript/advectionDiffusion1D/advectionDiffusion1D.js
@@ -39,8 +39,8 @@ model.setMeshConfig({
 });
 
 // Define boundary conditions
-model.addBoundaryCondition("0", ["constantValue", 1]); // Left boundary, u(0) = 1
-model.addBoundaryCondition("1", "zeroGradient"); // Right boundary, zero gradient (du/dx = 0)
+model.addBoundaryCondition("0", ["constantValue", 1]); // Left boundary
+model.addBoundaryCondition("1", "zeroGradient"); // Right boundary
 
 // Set solver method
 model.setSolverMethod("lusolve");
diff --git a/examples/heatConductionScript/README.md b/examples/heatConductionScript/README.md
@@ -1,4 +1,4 @@
-<img src="https://feascript.github.io/FEAScript-website/assets/feascript-heat-transfer.png" width="80" alt="FEAScript Logo">
+<img src="https://feascript.github.io/FEAScript-website/assets/feascript-heat-transfer.png" width="80" alt="FEAScript heatConduction Logo">
 
 # Heat Conduction Examples
 
diff --git a/examples/heatConductionScript/heatConduction1DWall/heatConduction1DWall.js b/examples/heatConductionScript/heatConduction1DWall/heatConduction1DWall.js
@@ -31,8 +31,8 @@ model.setMeshConfig({
 });
 
 // Define boundary conditions
-model.addBoundaryCondition("0", ["convection", 1, 25]);
-model.addBoundaryCondition("1", ["constantTemp", 5]);
+model.addBoundaryCondition("0", ["convection", 1, 25]); // Left boundary
+model.addBoundaryCondition("1", ["constantTemp", 5]); // Right boundary
 
 // Set solver method (optional)
 model.setSolverMethod("lusolve");
diff --git a/examples/heatConductionScript/heatConduction2DFin/heatConduction2DFin.js b/examples/heatConductionScript/heatConduction2DFin/heatConduction2DFin.js
@@ -33,10 +33,10 @@ model.setMeshConfig({
 });
 
 // Define boundary conditions
-model.addBoundaryCondition("0", ["constantTemp", 200]);
-model.addBoundaryCondition("1", ["symmetry"]);
-model.addBoundaryCondition("2", ["convection", 1, 20]);
-model.addBoundaryCondition("3", ["constantTemp", 200]);
+model.addBoundaryCondition("0", ["constantTemp", 200]); // Bottom boundary
+model.addBoundaryCondition("1", ["symmetry"]); // Left boundary
+model.addBoundaryCondition("2", ["convection", 1, 20]); // Top boundary
+model.addBoundaryCondition("3", ["constantTemp", 200]); // Right boundary
 
 // Set solver method (optional)
 model.setSolverMethod("lusolve");
diff --git a/examples/heatConductionScript/heatConduction2DFin/heatConduction2DFinGmsh.js b/examples/heatConductionScript/heatConduction2DFin/heatConduction2DFinGmsh.js
@@ -52,10 +52,10 @@ async function main() {
   });
 
   // Define boundary conditions
-  model.addBoundaryCondition("0", ["constantTemp", 200]); // bottom boundary
-  model.addBoundaryCondition("1", ["constantTemp", 200]); // right boundary
-  model.addBoundaryCondition("2", ["convection", 1, 20]); // top boundary
-  model.addBoundaryCondition("3", ["symmetry"]); // left boundary
+  model.addBoundaryCondition("0", ["constantTemp", 200]); // Bottom boundary
+  model.addBoundaryCondition("1", ["constantTemp", 200]); // Right boundary
+  model.addBoundaryCondition("2", ["convection", 1, 20]); // Top boundary
+  model.addBoundaryCondition("3", ["symmetry"]); // Left boundary
 
   // Solve the problem
   const { solutionVector, nodesCoordinates } = model.solve();
diff --git a/examples/heatConductionScript/heatConduction2DFin/heatConduction2DRhomFinGmsh.js b/examples/heatConductionScript/heatConduction2DFin/heatConduction2DRhomFinGmsh.js
@@ -52,10 +52,10 @@ async function main() {
   });
 
   // Define boundary conditions
-  model.addBoundaryCondition("0", ["constantTemp", 200]); // bottom boundary
-  model.addBoundaryCondition("1", ["constantTemp", 200]); // right boundary
-  model.addBoundaryCondition("2", ["convection", 1, 20]); // top boundary
-  model.addBoundaryCondition("3", ["symmetry"]); // left boundary
+  model.addBoundaryCondition("0", ["constantTemp", 200]); // Bottom boundary
+  model.addBoundaryCondition("1", ["constantTemp", 200]); // Right boundary
+  model.addBoundaryCondition("2", ["convection", 1, 20]); // Top boundary
+  model.addBoundaryCondition("3", ["symmetry"]); // Left boundary
 
   // Solve the problem
   model.setSolverMethod("lusolve");
diff --git a/src/FEAScript.js b/src/FEAScript.js
@@ -15,7 +15,7 @@ import { prepareMesh } from "./mesh/meshUtilsScript.js";
 import { assembleFrontPropagationMat } from "./models/frontPropagationScript.js";
 import { assembleGeneralFormPDEMat, assembleGeneralFormPDEFront } from "./models/generalFormPDEScript.js";
 import { assembleHeatConductionMat, assembleHeatConductionFront } from "./models/heatConductionScript.js";
-import { assembleStokesMatrix } from "./models/stokesScript.js";
+import { assembleCreepingFlowMatrix } from "./models/creepingFlowScript.js";
 import { runFrontalSolver } from "./methods/frontalSolverScript.js";
 import { basicLog, debugLog, warnLog, errorLog } from "./utilities/loggingScript.js";
 
@@ -200,23 +200,23 @@ export class FEAScriptModel {
         });
         solutionVector = linearSystemResult.solutionVector;
       }
-    } else if (this.solverConfig === "stokesScript") {
-      // Use regular linear solver methods for steady Stokes flow
-      const stokesResult = assembleStokesMatrix(meshData, this.boundaryConditions);
-      jacobianMatrix = stokesResult.jacobianMatrix;
-      residualVector = stokesResult.residualVector;
+    } else if (this.solverConfig === "creepingFlowScript") {
+      // Use regular linear solver methods for steady creeping flow
+      const creepingFlowResult = assembleCreepingFlowMatrix(meshData, this.boundaryConditions);
+      jacobianMatrix = creepingFlowResult.jacobianMatrix;
+      residualVector = creepingFlowResult.residualVector;
 
       const linearSystemResult = solveLinearSystem(this.solverMethod, jacobianMatrix, residualVector, {
         maxIterations: options.maxIterations ?? this.maxIterations,
         tolerance: options.tolerance ?? this.tolerance,
       });
       solutionVector = linearSystemResult.solutionVector;
 
-      // Store Stokes-specific metadata for solution extraction
-      this._stokesMetadata = {
-        totalNodesVelocity: stokesResult.totalNodesVelocity,
-        totalNodesPressure: stokesResult.totalNodesPressure,
-        pressureNodeIndices: stokesResult.pressureNodeIndices,
+      // Store creeping-flow-specific metadata for solution extraction
+      this._creepingFlowMetadata = {
+        totalNodesVelocity: creepingFlowResult.totalNodesVelocity,
+        totalNodesPressure: creepingFlowResult.totalNodesPressure,
+        pressureNodeIndices: creepingFlowResult.pressureNodeIndices,
       };
     }
     console.timeEnd("totalSolvingTime");
diff --git a/src/models/creepingFlowScript.js b/src/models/creepingFlowScript.js
@@ -15,7 +15,7 @@ import { FlowBoundaryConditions } from "./flowBoundaryConditions.js";
 import { basicLog, debugLog, errorLog } from "../utilities/loggingScript.js";
 
 /**
- * Function to assemble the Jacobian matrix and residual vector for the steady Stokes flow model
+ * Function to assemble the Jacobian matrix and residual vector for the steady creeping flow (Stokes) model
  * using Taylor-Hood (Q2-Q1) mixed finite elements
  *
  * DOF ordering in the assembled system:
@@ -39,8 +39,8 @@ import { basicLog, debugLog, errorLog } from "../utilities/loggingScript.js";
  * classic stiffness/conductivity matrix and `residualVector`
  * corresponds to the traditional load (RHS) vector.
  */
-export function assembleStokesMatrix(meshData, boundaryConditions) {
-  basicLog("Starting Stokes flow matrix assembly...");
+export function assembleCreepingFlowMatrix(meshData, boundaryConditions) {
+  basicLog("Starting creeping flow matrix assembly...");
 
   // Extract mesh data
   const {
@@ -56,10 +56,10 @@ export function assembleStokesMatrix(meshData, boundaryConditions) {
 
   // Validate mesh configuration
   if (meshDimension !== "2D") {
-    errorLog("Stokes solver requires a 2D mesh");
+    errorLog("Creeping flow solver requires a 2D mesh");
   }
   if (elementOrder !== "quadratic") {
-    errorLog("Stokes solver requires quadratic elements for Taylor-Hood (Q2-Q1) formulation");
+    errorLog("Creeping flow solver requires quadratic elements for Taylor-Hood (Q2-Q1) formulation");
   }
 
   // Number of velocity nodes (Q2) is the total number of nodes in the quadratic mesh
@@ -96,7 +96,7 @@ export function assembleStokesMatrix(meshData, boundaryConditions) {
   const totalDOFs = 2 * totalNodesVelocity + totalNodesPressure;
 
   debugLog(
-    `Stokes DOFs: ${totalNodesVelocity} velocity nodes (Q2), ${totalNodesPressure} pressure nodes (Q1), ${totalDOFs} total DOFs`,
+    `Creeping flow DOFs: ${totalNodesVelocity} velocity nodes (Q2), ${totalNodesPressure} pressure nodes (Q1), ${totalDOFs} total DOFs`,
   );
 
   // Initialize Jacobian matrix and residual vector
@@ -245,7 +245,7 @@ export function assembleStokesMatrix(meshData, boundaryConditions) {
   );
 
   flowBoundaryConditions.imposeDirichletBoundaryConditions(residualVector, jacobianMatrix);
-  basicLog("Stokes flow matrix assembly completed");
+  basicLog("Creeping flow matrix assembly completed");
 
   return {
     jacobianMatrix,

Original file line number	Diff line number	Diff line change
`@@ -1,4 +1,4 @@`
`1`		`-<img src="https://feascript.github.io/FEAScript-website/assets/feascript-front-propagation.png" width="80" alt="FEAScript Logo">`
	`1`	`+<img src="https://feascript.github.io/FEAScript-website/assets/feascript-front-propagation.png" width="80" alt="FEAScript frontPropagation Logo">`
`2`	`2`
`3`	`3`	`# Front Propagation Examples`
`4`	`4`