Inspection of the downforce I made the model of the rear spoiler, and we tested the downforce which raised one of the most important elements, a grip by modern car and racing car which terminated of the state-of-the-art.
I write the report here. In addition, the experiment used the chemical laboratory of the school.
Summary
This contents which went are following two
1． Confirmation 2 of the flow of the air when I exposed the model of the rear spoiler to wind using an incense stick from the front. Confirmation of the real numerical value (g) of the downforce with this model
The tool which I used
・Dryer
・Model (as for the alar part 302m X 199m/ slant 22 degrees) of the rear spoiler
・Dozens of incense sticks
・Chair (to prevent wind from the side)
・Electronic scales (I display it to a lower three figure)
A method and result
1． I bundle it up and set fire to a fixed incense stick and am fixed by hand in the position close to a model. And I attach a dryer in velocity of the wind "weak", "cold water".
⇒I understand that the smoke of the incense stick moves along the slant of the model in this way. It is hard to understand it a little.
2． The setting of the dryer is 1. As well as と. I guessed wind right for approximately 20 seconds and measured a change of the electronic figure numerical value and examined the maximum and the minimum and took the average and examined a value of generous downforce (g).
※It was difficult to measure the numerical value that was definite because the wind was very unstable.
⇒ clogging
(Maximum + minimum value) ÷ 2
If you assign to this it means that,
The maximum value is 17.026 (g)
The minimum value is 14.776 (g)
So average is
15.901 (g)
It becomes.
Since such thing lift that is working about 15.901g it means that is down force that is working 15.901g.
consideration(I will include aside)
You can be calculated by the following formula lift (downforce).
Lift (kg) = 1/2 × × air density airspeed ^ × coefficient of lift × wing area
Air density (you will be omitted unit is complex) 0.125 at sea level on
The lift coefficient when the 22 degrees angle will be (m ^) 0.060098 1.58, if you calculate the area of the wing part of this model.
I think part of unknown reason is it is more, but you go a little more (laughs)
It is possible to calculate the theoretical value of downforce if you ran it with the car actually this model In the light of the above.
In some examples,
It follows that about ※ 4.6kg When we assign to an expression that I do not know the reason of this just because it becomes to 27.8m per second when I calculated when the 100km per hour speed.
And say what it means, it's such a weight that has become heavier 4.6kg when running at a speed 100km.
※ I was calculated at 2 digit significant digits.
Down force will be 18kg when I calculated so 55.6m per second at the time of 200km per hour as well.
It was a very small value and about 15g in this experiment, but downforce are you acting properly be less so for example, including the value of the theory.
Such a down force is very interesting have been applied to such as DRS of F1 and road cars currently.
It has become very complex, but this time Thank you for reading.
Written by S
