Creeping flow in a 2D lid-driven cavity, multi-threaded.

The code below shows how to use FEAScript with a web worker. The velocity field is decomposed and plotted as contour plots.

<body>
  <!-- ...body region... -->
  <script type="module">
    import {
      FEAScriptWorker,
      plotSolution,
      printVersion,
    } from "https://core.feascript.com/src/index.js";

    window.addEventListener("DOMContentLoaded", async () => {
      console.log("FEAScript version:", printVersion);

      // 1. Create the model in a web worker and select the physics
      const model = new FEAScriptWorker();
      await model.ping(); // Wait until the worker is ready
      await model.setModelConfig("creepingFlowScript", {
        coefficientFunctions: {
          viscosity: 1, // μ
        },
      });

      // 2. Define the mesh (creeping flow needs quadratic elements)
      await model.setMeshConfig({
        meshDimension: "2D",
        elementOrder: "quadratic",
        numElementsX: 12,
        numElementsY: 6,
        maxX: 4,
        maxY: 2,
      });

      // 3. Apply the boundary conditions
      await model.addBoundaryCondition("0", ["constantVelocity", 0, 0]); // Bottom wall
      await model.addBoundaryCondition("1", ["constantVelocity", 0, 0]); // Left wall
      await model.addBoundaryCondition("2", ["constantVelocity", 1, 0]); // Moving lid
      await model.addBoundaryCondition("3", ["constantVelocity", 0, 0]); // Right wall

      // 4. Solve
      await model.setSolverMethod("lusolve");
      const result = await model.solve();

      // 5. Plot the results
      const modelInfo = await model.getModelInfo();
      plotSolution(modelInfo, result, "contour", "velocityMagnitudeCanvas");
      plotSolution(modelInfo, result, "contour", "uVelocityCanvas", { field: "u" });
      plotSolution(modelInfo, result, "contour", "vVelocityCanvas", { field: "v" });

      // 6. Terminate the worker
      model.terminate();
    });
  </script>
  <!-- ...rest of body region... -->
</body>

Below are the 2D contour plots of the computed velocity magnitude \(|\mathbf{u}| = \sqrt{u^2+v^2}\), horizontal velocity component \(u\), and vertical velocity component \(v\). These plots are generated in real time using FEAScript.