Torsion of a racing car aerofoil

Torsion of a racing car aerofoil.

An aerofoil is manufacturing from a carbon fibre reinforced polymer skin thickness 1.5mm  with the geometry, lengths and areas given in the accompanying assignment XL spread sheet containing a corresponding SET No. ranging from 1 to 14.

use SET No 6.

A schematic of the cross-section is shown in fig A1. Using this information complete the following tasks stated below and answer the questions at the end of the tasks.

 

Position Length (mm)
AB  
BC  
CD  
DE  
EF  
FG  
GH  
HA  
CG  

 

Area Size (mm2)
ABH  
BCGH  
CDFG  
DEF  

 

 

 

 

 

Table A1, for your actual lengths and areas see your set number in the spreadsheet at the appendix.

 

 

 

 

 

 

 

 

 

 

Assume for the skin the following properties, Mean E fibre = 350 GPa, volume fraction = 65%, design strain 0.5%, and effective length is 1.6m.

Task 1 (40%)

Assuming the car can achieve a maximum speed of 220 mph with a lift coefficient of 1.6 for the aerofoil and the centre of twist is approximately is 15% of the chord length AE;determine the maximum angle of twist and shear stress induced in the aerofoil for this case.

 

Task 2 (10%)

The actual aerofoil however has closed ends with a small plate of the same material. Estimate how this will change your predicted answer and indicate the positions along the length were this is most affected using a simple sketch.

Task 3 (25%)

If under race condition the section is subject to an impact at the mid-point between the end plates which damages section FG. Estimate the increase in angle of twist and the maximum induced shear stress due this impact.

Torsion of a racing car aerofoil Supplementary questions

  1. If the aerofoil was manufactured from aluminium comment on how the behaviour of the aerofoil would react to the conditions in tasks 1 to 3 inclusive (10%)
  2. Describe how the “centre of twist” affects the loading (5%)
  3. Describe briefly how the composite part would be joined and how you could estimate the stress in the adhesive. (10%)

 

 

LOs for this work are as follows:

Demonstrate a comprehensive understanding of the scientific principles of mechanical and related engineering disciplines (US1m

Demonstrate an awareness of developing technologies related to mechanical engineering. (US4m)

Submission method

 

On completion of your task you will need to upload your solution via the moodle link provided by your module tutors.

 

Appendix

 

Position Length(mm) DIMENSIONS
         
      Area Size (mm2)           Area Size (mm2)
AB 78   ABH 960     AB 75   ABH 945
BC 86   BCGH 2700     BC 83   BCGH 2685
CD 60   CDFG 2300     CD 57   CDFG 2285
DE 38   DEF 160     DE 35   DEF 145
EF 38           EF 35      
FG 64           FG 61      
GH 92   SET 1       GH 89   SET 5  
HA 80           HA 77      
CG 36           CG 33      
                       
AB 82   ABH 976     AB 72   ABH 930
BC 90   BCGH 2716     BC 80   BCGH 2670
CD 64   CDFG 2316     CD 54   CDFG 2270
DE 42   DEF 176     DE 32   DEF 130
EF 42           EF 32      
FG 68           FG 58      
GH 96           GH 86      
HA 84   SET 2       HA 74   SET 6  
CG 40           CG 30      
                       
AB 86   ABH 991     AB 68   ABH 918
BC 94   BCGH 2731     BC 76   BCGH 2658
CD 68   CDFG 2331     CD 50   CDFG 2258
DE 46   DEF 191     DE 28   DEF 118
EF 46           EF 28      
FG 72           FG 54      
GH 100   SET 3       GH 82      
HA 88           HA 70   SET 7  
CG 44           CG 26      

The grading system and assessment criteria are those as described in the module handbook in sections 11, 13 and 14.

 

 

Torsion of a racing car aerofoil

Last Updated on February 10, 2019 by EssayPro