1. Truckin’ Trailers
by: Walker Preston

2. Question
What areas on a semi truck trailer produce drag?

3. Back Ground
I’m really into trucks and hauling and I know that MPG(Miles Per Gallon) is important because of gas prices.So, I wanted to test if sideskirts and truck cone reduce drag.

4. Hypothesis
If adding aerodynamic accessories to a semi truck trailer it will reduce drag.

5. variables independent: Aerodynamic accessories
dependent: Aerodynamic drag, Fuel economy
constants: the wind tunnel, wind speed,trailer

6. procedure gather materials Place truck and trailer in wind tunnel
Base line test without aerodynamics
Place smoke in front of the fan
record data
Test with aerodynamic accories

7. data

9. Data

13. conclusion Do semi truck trailer accessories reduce drag?
My experiment went as planned, the wind tunnel work really well and the accessories worked like in real life. I did this experiment with and without the accessories. With the accessories the smoke flowed smoothly over the trailer and couldn’t see any wind spin up.
My data proved my hypothesis because the back of the truck had the most drag and with the truck cone it reduced drag. I learned that rounded surfaces lets air flow over it easier.

14. Changes
If I could change anything it would be the wind speed. I would use an anemometer to gage the wind speed accurately.
I would have improved the lighting inside the wind tunnel.