Page Comparison

Simulations on two different composite stack ups, figuring out the best material (unidirectional vs weave) for the catamaran.

Stackup 1

1. Unidirectional Prepreg (230 GPa) 0 degrees
2. Unidirectional Prepreg (230 GPa) 90 degrees
3. 5/8" Honeycomb Core
4. Unidirectional Prepreg (230 GPa) 90 degrees
5. Unidirectional Prepreg (230 GPa) 0 degrees

Stackup 2

1. Weave Prepreg (230 GPa) 0 degrees
2. Weave Prepreg (230 GPa) 45 degrees
3. 5/8" Honeycomb Core
4. Weave Prepreg (230 GPa) 45 degrees
5. Weave Prepreg (230 GPa) 0 degrees

Note: 0 degrees is the path from left to right on the catamaran

Workbench Setup

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Static Structural Setup

1. Fixed point at the center of the catamaran
2. 10000N of downwards force on the front driver side corner and the rear passenger side corner
3. 10000N of upwards force on rear driver side corner and the front passenger side corner

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Here are the results (The colors correspond to different values in stackup 1 vs stackup 2)

Stackup 1

1. Unidirectional Prepreg 0 degreesImage Removed
2. Unidirectional Prepreg 90 degreesImage Removed
3. 5/8" Honeycomb CoreImage Removed
4. Unidirectional Prepreg 90 degreesImage Removed
5. Unidirectional Prepreg 0 degreesImage Removed

Stackup 2

1. Weave Prepreg 0 degreesImage Removed
2. Weave Prepreg 45 degreesImage Removed
3. 5/8" Honeycomb CoreImage Removed
4. Weave Prepreg 45 degreesImage Removed
5. Weave Prepreg 0 degreesImage Removed

My initial analysis:

...

Good Torsional Rigidity = Good handling performance of a car.

It is basically defined how much force is required to twist the car by 1 degree, see picture below.

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ANSYS Setup:

1. Fix the back end of the car
2. Apply an upwards force of 10000N on a front corner of the car
3. Apply a downwards force of the same magnitude on the other front corner of the car
4. Look at Total Deformation, and see how much the front corners have moved
5. To see if the car has been twisted 1 degree, do the trigonometry, see picture below
   1. Image Added
   2. **Correction on photo** directional deformation should say total deformation instead
   3. To see how much directional deformation of a corner twists the car by 1 degree, use SOHCAHTOA and calculate:   total deformation = tan (1) x half the car width
6. Adjust the 10000N you applied on the corners of the car until you get the desired total deformation that twists the car by 1 degree

Read this article:

https://peer.asee.org/development-of-a-test-stand-for-determining-the-torsional-rigidity-of-a-formula-sae-space-frame.pdf