Abstract
This chapter discusses ways of measuring the characteristics of a vehicle and that of some of its components. Emphasis has been placed on methods that are straightforward and economical. Wind tunnel testing of models is not economical unless the team can obtain the wind tunnel time as part of a sponsorship. Nevertheless, a section documenting the construction and test of a quarter-scale model of the Table Top concept has been included. It will be useful, should an opportunity to test in a wind tunnel arise.
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Notes
- 1.
The vehicle operates in an atmospheric boundary layer.
- 2.
A Volkswagen 1600 notchback, type 31.
- 3.
Note that all three oils are flammable.
- 4.
It is possible that the yarns, if too closely spaced or too large, could trip the flow to turbulence.
- 5.
The flow approaching the model will itself contain some turbulence, although a small amount, in well-made tunnels. It is probably impossible to eliminate it entirely.
- 6.
Buckley (1974) contributes non-low-budget ideas for other measurements.
- 7.
The spreadsheet program probably calls it “regression analysis” or something similar.
- 8.
If the speed is represented by the “Nth-order” polynomial a0 + a1t + a2t2 + … + aNtN, the deceleration would be a1 + 2a2t +…+ NaNtN−1
- 9.
Or else, note when the square of the correlation coefficient is closest to 1.0 as calculated by the spread sheet.
- 10.
It is possible that the widest and tallest parts of the car may not be at the same axial location. Select one or the other as the reference location and project into that plane.
- 11.
Be sure not to exceed the rated voltage of the lamp; they are quite easily burned out by this. Have some replacements in hand.
References
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Thacher, E. (2015). Testing. In: A Solar Car Primer. Springer, Cham. https://doi.org/10.1007/978-3-319-17494-5_12
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