Roof challenge
ROOF
An automobile roof or car top is the portion of an automobile that sits above the passenger compartment, protecting the vehicle occupants from sun, wind, rain, and other external elements. Because the earliest automobiles were designed in an era of horse-drawn carriages, early automobile roofs used similar materials and designs.
The Automobile roof consists of the following parts:
- The outer panel
- Front roof Rail
- Bow Roof
- Centre Roof Rail
- Rear Roof Rail
Outer Panel:
Bow Roof
Center Roof Rail:
Front Roof Rail
Back Roof Rail:
Roof:
Draft Analysis:
Heat Distortion:
Heat distortion is the temperature at which metal softens and deforms under a specified load. From Heat distortion criteria, roof strength can be enhanced by appropriate positioning of bow roof rails. This study is done to check the ability of the roof to withstand high temperature with respect to positioning of reinforcements which contributes to increase strength.
| Heat Distortion | ||||||||||
| S.No | Description | Rx | Ry | R=2(Rx*Ry)/(Rx+Ry) | I | L | t | R^2/t | W | Results |
| 1 | FR & 1st | 949.89 | 1259.45 | 1082.983 | 1122.75 | 2033.7 | 0.75 | 1563803 | 2.102256 | OK |
| 2 | 1st & CTR | 919.15 | 6791.43 | 1619.163 | 1083.93 | 2033.7 | 0.75 | 3495585 | 2.095292 | OK |
| 3 | CTR & 2nd | 828.84 | 11797.97 | 1548.868 | 1064.08 | 2033.7 | 0.75 | 3198655 | 2.067964 | OK |
| 4 | 2nd & RR | 855.22 | 2004.3 | 1198.885 | 1048.62 | 2033.7 | 0.75 | 1916433 | 2.027237 | OK |
Snow Load Prediction
Snow load criteria study is done to check the withstand ability when the snow loads over the roof during winter in snow fall regions. This study will also analyze the roof that whether the permanent deformation occurs after removing the snow load. That it may bend but needs to be bounce back to its position.
| Snow Conditions | ||||||||||||
| S.No | Description | Iy | α | Lx | Ly | y | s | Rx | Ry | t | Qr | Results |
| 1 | FR & 1st | 2709.064 | 0.943881934 | 1165.519 | 2121.44 | 404.75 | 402.535 | 4116.37 | 3360.49 | 0.75 | 28.69736 | OK |
| 2 | 1st & CTR | 4905.6 | 0.873425349 | 1125.91 | 2121.44 | 400.32 | 442.09 | 3803.7 | 4470.65 | 0.75 | 41.75134 | OK |
| 3 | CTR & 2nd | 1134.65 | 0.964166451 | 1103.1 | 2121.44 | 483.86 | 390.21 | 4259.75 | 10872.78 | 0.75 | 2.963268 | NG |
| 4 | 2nd & RR | 0 | 2121.44 | 296.56 | 0.75 | |||||||
Moment of inertia:
Calculations:
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Conclusion:
The Roof has been designed and calculated the Heat distortion and snow condition.
ZIP File Attached