The Line Mass Source node adds mass flow originating from a tube of infinitely small radius. In case of a point feature, the tube lies along the virtual layer edge perpendicular to the layer surface.

In the Shell Properties section you determine on which layer edge the Line Mass Source is defined. You can select individual layers within one layered material. To specify different settings for different layered materials or for different layers within one layered material, you have to add one boundary node for each layered material or for each layer, respectively. You can visualize the selected layers by clicking the Layer Cross Section Preview () and Layer 3D Preview () buttons.

Enter a value or expression for the source strength, N0 (SI unit: kg/(m·s)). A positive value results in mass injection from the line into the computational domain, and a negative value means that the mass is removed from the computational domain.