Set the viscosity in the creeping flow tutorials

Show the viscosity coefficient (μ = 1) in the creeping flow tutorials
(main thread and worker).

Author: nikoscham

tutorials/lid-driven-cavity-2d-creeping-flow-worker.html

@@ -225,7 +225,11 @@ <h1>
       // 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");
+      await model.setModelConfig("creepingFlowScript", {
+        coefficientFunctions: {
+          viscosity: 1, // μ
+        },
+      });
 
       // 2. Define the mesh (creeping flow needs quadratic elements)
       await model.setMeshConfig({
@@ -325,7 +329,11 @@ <h1>
                 await model.ping();
 
                 // Set solver configuration
-                await model.setModelConfig("creepingFlowScript");
+                await model.setModelConfig("creepingFlowScript", {
+                  coefficientFunctions: {
+                    viscosity: 1, // μ
+                  },
+                });
 
                 // Define mesh configuration
                 const numElementsX = 12;

tutorials/lid-driven-cavity-2d-creeping-flow.html

@@ -207,7 +207,8 @@ <h1>Creeping Flow in a <span class="accent">2D Lid-Driven Cavity Tutorial</span>
               \(\nabla \cdot \mathbf{u} = 0\) and \(-\mu \nabla^{2} \mathbf{u} + \nabla p = \mathbf{0}\),
               where \(\mathbf{u} = (u,v)\) is the velocity vector, \(p\) is the pressure and \(\mu\) is the
               dynamic viscosity. In the FEAScript implementation below, we set the viscosity coefficient to
-              \(\mu = 1.0\).
+              \(\mu = 1.0\) with the <code>viscosity</code> coefficient of the model (a number, or a function of
+              \(x\) and \(y\) for a varying viscosity).
             </p>
 
             <div class="center-image">
@@ -260,7 +261,11 @@ <h1>Creeping Flow in a <span class="accent">2D Lid-Driven Cavity Tutorial</span>
 
       // 1. Create the model and select the physics
       const model = new FEAScriptModel();
-      model.setModelConfig("creepingFlowScript");
+      model.setModelConfig("creepingFlowScript", {
+        coefficientFunctions: {
+          viscosity: 1, // μ
+        },
+      });
 
       // 2. Define the mesh (creeping flow needs quadratic elements)
       model.setMeshConfig({
@@ -368,7 +373,11 @@ <h1>Creeping Flow in a <span class="accent">2D Lid-Driven Cavity Tutorial</span>
                 const model = new FEAScriptModel();
 
                 // Set model configuration
-                model.setModelConfig("creepingFlowScript");
+                model.setModelConfig("creepingFlowScript", {
+                  coefficientFunctions: {
+                    viscosity: 1, // μ
+                  },
+                });
 
                 // Define mesh configuration
                 model.setMeshConfig({