Week 2 Challenge : Surface meshing on a Pressure valve

OBJECTIVE:-

1. To perform surface mesh on given model using ANSA and also check geometrical errors and perform Topology cleanup accordingly.
2. To Set three different target lengths as 1mm, 3 mm and 5 mm and mesh the model for each case and element type must be Tria.
3. Report on meshing process and also mention which case is giving good results along with the reason.

Procedure:-

1. Import the Geometry.
2. Geometry Check Up (Hot Points,Overlapping Surfaces, etc)
3. Assigning the PID's
4. Assigning the Perimeter & Macros
5. Selection of Spot Mesh from Mesh Generation in mesh Module.

1. Import the Geometry:-

Import the geometry using open in file menu from the Specified Path.

2. Geometry Check Up

Geometry Checkup is done to make single cons to faces by creating new face or using fill hole. And remove extra Hot points and overlaping Surfaces to prevent irregularities in shape of our geometry.

This step is done to check if there are any errors in the model like unclosed faces, Superimposing faces,etc..

upper Toolbar→

Checks →geometry→Visible→execute→check for the green tick beside geometry→

close the window

Before Geometry Clean Up

WireFrame model:-

Shadowed View:-

In Geometry Single cons (red) needs to be converted to double cons (face) and the intersected parts needs to be cleaned.

After Geometry Clean Up:-

WireFrame model:-

Shadowed View:-

Checks Manager after Geometry clean Up

In geometry there are some warning as these are not errors we can neglect them,Or we resolve them one by one.

3. Assigning the PID's:-

Define a number of entities into PID's such as body, spring,column,outer,inner,valve head etc.

upper toolbar > PID > right click > New > enter nameof PID > Select No. of entities

4. Assigning the Perimeter & Macros

Upper toolbar > Mesh module >

Perimeters > Length >

Select Perimeters >select the whole entity(Same Mesh Size of every PID) or each PID to which we want Mesh>

Similarly In Macros.

Upper toolbar>Mesh module >

Perimeters >Length>

Select Macros >select the whole entity to which we want Mesh>

These Perimeter and Macro Length is also defined for each case(3mm,5mm)in the same way.

Here We have 3 cases of different Mesh Sizes (1mm, 3mm,5mm). So, Perimeter and Macro Should be defined accordingly.

5. Selection of Spot Mesh from Mesh Generation in mesh Module

Upper Toolbar > Mesh module > Mesh Generation > Spot Mesh > visible

CASE 1:- Element Length= 1mm

Mesh quality is good, precise to geometry.

Minimum Simulate errors

Maximum Simulation Time

CASE 2:- Element Length= 3mm

as compared 1mm mesh size

Mesh quality is poor, and not precise to geometry

More Simulate errors

Min Simulation Time

CASE 3:- Element Length= 5mm

as compared 1mm and 3mm mesh size

Mesh quality is poor, and not precise to geometry

More Simulate errors

Min Simulation Time

Result :- As 1 mm is perfectly aligned to geometry and is not having any distortion is 1mm is very good Mesh size as compared to 3 mm & 5 mm, In 3 mm the geometry distortion is visible in the above images Case-2, When Mesh size is 5 mm the Geometry became worst (poorer) as compared to 3mm and 1mm (case-3). Increasing Meshing size makes the geometry of Model distorted which leads to Simulation errors. Optimum mesh size should be selected (here it should be between 1mm and 3mm).

CONCLUSION:- Optimum mesh size should be selected, as minimum mesh size leads to slower simulation Rate but high accuracy,and larger mesh size leads to more simulation errors.