Building the Mesh

This section describes the step-by-step procedure for preparing the mesh for the tank filling model that contains tank, fuel line and nozzle. The mesh is used for creating the General Mesher.

Fuel line Mesh

Select General Mesher in the Mesh Panel.
Select CAD Surfaces Fuel_line_mgi_nozzle, Fuel_line_mgi_tank and Fuel_line_wall in the Geometric Entities Panel.
Enter Maximum Cell Size as 0.004, Minimum Cell Size as 0.0003 and Cell Size on Surfaces as 0.002 in the Properties Panel.
Click Create Mesh. A new mesh Fuel_line is created under Built Meshes in the Geometric Entities Panel.
The meshed volume Fuel_line is generated under Volumes.

Figure 11.105 - Fuel line mesh settings

Nozzle

Select General Mesher in the Mesh Panel.
Select CAD Surfaces Nozzle_air_out, Nozzle_fuel_in, Nozzle_mgi_fuel_line and Nozzle_wall in the Geometric Entities Panel.
Enter Maximum Cell Size as 0.004, Minimum Cell Size as 0.0003 and Cell Size on Surfaces as 0.002 in the Properties Panel.
Click Create Mesh. A new mesh Nozzle is created under Built Meshes in the Geometric Entities Panel.
The meshed volume Nozzle is generated under Volumes.

Figure 11.106 - Nozzle mesh settings

Tank Mesh

Select General Mesher in the Mesh Panel.
Select CAD Surfaces Tank_mgi_fuel_line, Tank_vent_out, and Tank_wall in the Geometric Entities Panel.
Select Advanced Mode from the Setup Options drop-down list.
Enter Maximum Cell Size as 0.008, Minimum Cell Size as 0.0003 and Cell Size on Surfaces as 0.004 in the Properties Panel.
Select Cylindrical Zone under Create a Refinement Zone drop-down list
Enter the parameter under the Refine Zone Options list as follows.

Cell Size: 0.004
Top Circle Center: 4.014, -2.615, 0.272 m
Bottom Circle Center: 3.614, -2.614, 0.158 m
Zone Radius: 0.03

Select Box Zone under Create a Refinement Zone drop-down list.

Enter the parameter under the Refine Zone 2 list as follows:

Cell Size: 0.004
First Corner: 3.616, -2.783, 0.158
Diagonal Corner: 4.013, -2.445, 0.201

Click Create Mesh. A new mesh Tank is created under Built Meshes in the Geometric Entities Panel.

The meshed volume Tank is generated under Volumes.

Figure 11.107 - Tank mesh settings

The mesh created for the fluid domain is shown below.

Figure 11.108 - Mesh

Figure 11.109 - Cross-sectional view

Create interfaces

In this section, the Mismatched Grid Interfaces (MGI) are generated between boundaries.

The steps to create the MGI is as follows:

Geometric Entities Panel > Volumes > Boundaries, select entities shown under boundaries (see, Table 11.4).
Click Connect Selected Boundaries via MGI icon to create the MGI entities (see, Figure 11.110).

A group display of entities can be viewed using the Group Entities by Volumes/Types icon at Geometric Entities Panel toolbar.

Connecting interfaces	Boundaries	Entity
Fuel line and Nozzle	Fuel_line_mgi_nozzle, Nozzle_mgi_fuel_line	MGI01
Fuel line and Tank	Fuel_line_mgi_tank, Tank_mgi_fuel_line	MGI02

Table 11.4 - Creating interfaces

The new entities are created under MGI in Volumes (see, Figure 11.111).

Figure 11.110 - Connecting fuel line and nozzle

Figure 11.111 - Created interfaces

Note: If MGIs are created by connecting the wrong boundaries, delete the created MGIs by clicking on Delete Selected Geometric Entity icon and then recreate the MGIs.