PFI Engine - Surface Preparation and Boundary Flagging

Aim:

Preparing the surface and flagging the respective boundaries on a given SI8 - PFI engine model.

Theory:

A spark ignited (SI) engine is a gasoline engine which creates combustion by igniting the air-fuel mixture by means of a spark plug. The fuel can be introduced by means of a carburetor or fuel injectors. The engine used for the experiment, however, is a port fuel injected gasoline engine. It is a single cylinder with two intake and exhaust valves. A simple geometry is provided to understand, make the surface corrections and flag the necessary boundaries correctly.

To flag the boundaries and define the regions, the \'Fence\' option is used. It splits the area into two regions by creating a boundary/fence around the selected part. If the fencing is correct, the selected part can be flagged and named accordingly.

Converge has many options under the \'Repair\' menu where you can fix irregularities in geometries of different shapes by using options such as\'Patch\',\'Stitch\',\'Align\', etc. Converge also has a neat feature of pointing out where and what type of irregularities are present by using the \'Diagnosis\' option. If no problems exist, all the options are highlighted by a green tick mark. Note that it is always easier to fix errors once boundary flagging is complete.

Fig 1: Intersection and Non-manifold errors

Fig 2: Normal orientation errors

Fig 3: Open edge errors

Fig 4: Different colors representing the boundaries

Fig 5: The flagged geometry without the edges

Fig 6: The colors grouped by regions

Fig 7: Inside the cylinder head with the valves and the spark plug

Fig 8: The exhaust and intake valves

Fig 9: Isometric view

Result:

The images above show the process of surface preparation, boundary flagging and grouping the colour by regions. All these steps are mandatory in order to run a proper simulation and to get the desired animation.