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
Buckley, B. S. (1974). Road test aerodynamic instrumentation. Proceedings of Automobile Engineering Meeting, Toronto, Canada, October 21–25, 1974, SAE paper 741030.
Cogotti, A. (1983). Aerodynamics of car wheels. Technological advances in vehicle design series, SP3. In M. A. Dorgham (Ed.), Impact of Aerodynamics on Vehicle Design, (pp. 173–196). Interscience Enterprises Ltd: La Motte Chambers. (Int. J. of Vehicle Design).
Dominy, R. G. (1991). A technique for the investigation of transient aerodynamic forces on road vehicles in cross winds. Journal of Automobile Engineering, 205, 245–250. (Proceedings of the Institution of Mechanical Engineers vol 205, Part D).
Dyke, M. (1960). Flow visualization. Library Bib’y. No. 222. Royal Aircraft Establishment, Ministry of Aviation, London.
Hoerner, S. F. (1950). Determining drag of an automobile under actual road conditions. Automotive Industries, Sept 15, pp. 43, 96, 100.
Hucho, W.-H. (1987). Wind Tunnels for Automobile Aerodynamics. In W.-H. Hucho (Ed.), Aerodynamics of Road Vehicles (pp. 398–435). Boston: Butterworths.
Hurst, D. W., Allan, J. W., & Burgin, K. (1983). Pressure measurements on a full-scale tractor-trailer combination and comparison with data from wind-tunnel model tests. International Journal of Vehicle Design. Technological advances in vehicle design series, SP3. In M. A. Dorgham (Ed.), Impact of Aerodynamics on Vehicle Design (pp. 471–479).
Lucas, G. G., & Britton, J. D. (1970). Drag Data from deceleration tests and speed measurement during vehicle testing. In A. J. Scibor-Rylski (Ed.), Proceedings of First Symposium on Road Vehicle Aerodynamics, The City University, 6 & 7 November, 1969. London.
Korst, H. H., & Funfsinn, M. A. (1977). Determination of Effective Rolling Resistance by Coastdown Experiments on Smooth and Rough Roads. In R. H. Snyder, (Ed.), Tire Rolling Losses and Fuel Economy, SAE Conference Proceedings. P-74, (pp. 133–141). Society of Automotive Engineers, Warrendale.
Kurtz, D. W. (1980). Aerodynamic design of electric and hybrid vehicles: A guidebook. Jet Propulsion Laboratory: JPL Publication. (80–69 (NASA-CR-163744 and NTIS N81-12943).
Maltby, R. L. & Keating, R. F. A. (1960). Flow visualization in low-speed wind tunnels: Current British practice. Tech. Note Aero.2715, Royal Aircraft Establishment, Ministry of Aviation, London.
Merzkirch, W. (1987). Flow visualization. Orlando: Academic Press.
Morelli, A., Nuccio, P., & Visconti, A. (1981). Automobile aerodynamic drag on the road compared with wind tunnel tests. SAE 810186, SAE International Congress and Exposition, Cobo Hall. 23–27 Feb 1981.
Passmore, M. A., & Jenkins, E. G. (1988). A comparison of the coastdown and steady state torque methods of estimating vehicle drag forces. International Congress and Exposition, Detroit. 29 Feb–4 March 1988, SAE 880475.
Pershing, B., & Masaki, M. (1976). Estimation of vehicle aerodynamic drag. EPA-460/3-76-025 (NTIS PB 275 948). Washington, DC: National Technical Information Service.
SAE. (1996). Road load measurements and dynamometer simulation using coastdown techniques. (SAE J1263 Feb 1996) Society of Automotive Engineers Handbook, 2, 26.531–26.550.
Seal, M. R. (1991). Design for the ultimate Viking car 1972–1991. Proceedings S/EV 91 Solar and Electric Vehicle Symposium and Trade Show 26–27 Oct, Boxborough Massachusetts (pp. 26–44). Northeast Sustainable Energy Association, Greenfield.
Swift, A. (1991). Calculation of vehicle aerodynamic drag coefficients from velocity fitting of coastdown data. Journal of Wind Engineering and Industrial Aerodynamics, 37, 167–185.
Stanbrook, A. (1960). The surface oil flow technique as used in high speed wind tunnels in the United Kingdom. Tech. Note Aero.2712, Royal Aircraft Establishment, Ministry of Aviation, London.
Van Valkenburgh, P. G., Klein, R. H., & Kanianthra, J. (1982). Three-Wheel Passenger Vehicle Stability and Handling. (SAE 820140). SAE Transactions, vol. 90.
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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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