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By incorporating inverted compared to an aircraft airfoil sections into the sidepods of their car, the era of ground effects in Formula 1 was started.
A side skirt was connected to the edge of the sidepods and extended down to the road surface. This skirt helped maintain 2D flow characteristics that provide increased downforce and reduced drag compared to a typical 3D wing. The side skirts also hid the new device from the prying eyes of competitors.
Even so-called "flat bottomed" racing cars, such as those in F1, can create significant downforce from a well-shaped small diffuser. Cars without scope for a diffuser can still generate downforce from a slanted lower surface at the rear of the car in combination with a rear wing.
Undertray or underbody picture above Nico Rosberg's Mercedes AMG F1 W03, click on it for bigger picture is aerodynamically the strongest contributor to the lap time.
Very low drag to downforce ratio is important to take into consideration during design. Underbody is working in very close relationship with front wing and splitter in the front of the car feeding the air to underbody and diffuser on the back extracting the air from under the car. A Formula 1 car produces much of its downforce from its underside, and you can think of each component of it as a link in a long chain.
Change one without altering the rest and everything is then out of alignment—the car's aerodynamics simply won't work as intended. F1 rules prohibit under-car shaping or venturis, and mandate a minimum ride height enforced by a relatively low-tech wear plank attached underneath the car. Underbody must be, by the rules, completely flat, except for plank and Reference plane.
However, there is still scope to shape the diffuser area directly under and behind the rear axle line. As part of the package of aero changes designed to reduce downforce for and then againthe diffuser has undergone quite complex modifications. Moves to create a more standardised shape have removed the difference in height between the central and two outer sections and all three channels are now taller - mm rather than mm.
In addition, the diffuser has been moved rearwards, with its trailing edge now mm behind the rear axle - previously, it was level with the rear axle. Teams still use different trickery to increase efficiency of underbody and diffuser. For example, the forward barge board you can see on the picture of Mercedes F1 car up, acts solely as a vortex generator.
They're cambered like a wing. The rotational direction of that vortex will be counterclockwise, and because the vortex is traveling downward, it sends down-wash approaching the underbody, feeding it with additional air and acting as the curtain, which is very favorable.
It essentially generates more downforce. The car's keel split the column of incoming air underneath the monocoque sideways and out of the way. It's shaped very carefully and designed with the barge boards in mind to generate higher airspeed and thus low pressure. The sculpted sidepod turning vanes play a vital role in routing the dirty, turbulent wake of air coming off the front tires.
They delay how long it takes before that front-wheel dirty wake starts entering under the floor and taking downforce away. The leading edge of the floor will generat vortices that will then spin down underneath the floor, along the edge of the reference plane, and all of that vortical action reduces the total pressure under the floor and gives you more downforce.
The complication on the perfect diffuser and floor performance comes form the shape of the underbody of the Formula 1 car.
Meet the seven people who hold the keys to worldwide internet security
The area under the car is regulated to form basically two flat bottoms. All we normally see of the underbody is the splitter, sides and exit of the diffuser and sometimes, if seen from a low angle, the step under the cars floor. The stepped underbody was introduced to reduce the effectiveness of the diffuser, and the plank was introduced to prevent the teams running the very low ground clearances to enhance the effect of the diffuser. You can also find all relative data of underbody precisely described in FIA rules, but they are so complicated and hard to understand to anybody except F1 engineers, but you can try!!!
I will try to describe parts of the Formula 1 underbody, beginning from one closest to the ground - up. But first, a small explanation: Just as with any bodywork in the rules, these parts are not allowed to move or flex more that specified in regulations.
For the floor in comparison to the wings, there are few deflection tests commonly carried out during crash testthe main one being the splitter deflection test and fuel tank penetration test carried from below the floor. And here we go!! Plank There is an article in my F1 dictionary dedicated to plank or skid block as is called in f1 circles, so you can check there, but I will describe it here again in shorter version. Beneath the reference plane lies the skid block or 'plank' and running all the way along the reference plane.
It must run from the frontmost point of the reference plane at mm behind the front wheels centerline to the rear wheels centerline. It is not considered part of the floor for measurement purposes, and is there only to enforce a minimum ride height. It must be made out of a material with a specific gravity of between 1.
Typically the plank is wood based, either jabroc, a laminate of beechwood, although more exotic blends of woods and resins not unlike MDF have been used.
Must measure mm in width, with a tolerance of 2mm.
Although it decreases in thickness towards the edges to allow a smooth design, the plank most importantly, when measured through six pre-cut 5cm diameter holes, has a tolerance of just one 1mm on its 10mm thickness.
Holes in the plank allow measurement of the thickness and the cars reference plane to sit directly and exactly on right place on the FIA scrutineering platformfor legality checks over the course of a GP weekend. It is his first time, and his eyes regularly flick to the script.
To start with, things go according to plan. All but one of the 21 keyholders has been with the organisation since the very first ceremony. The initial selection process was surprisingly low-key: Since then, only one keyholder has resigned: Vint Cerfone of the fathers of the internet, now in his 70s and employed as "chief internet evangelist" by Google.
At the very first key ceremony, in Culpeper, Virginia, Cerf told the room that the principle of one master key lying at the core of networks was a major milestone. The ceremony administrator and the keyholders are all locked in an 8ft square cage.
Six minutes of quiet panic go by before they hit on a solution: Sirens blare and everyone piles out to mill around in the corridor until we can get back to the point script. Every deviation has to be noted on an official recordwhich everyone present must read and sign off at a later point.
Meanwhile, we use the downtime to snack: A security controller slams the safe door shut, triggering a seismic sensor, which in turn triggers door locks. The keyholders are locked in an 8ft square cage. In the wake of the ongoing revelations of NSA spying, and of undermined internet security, this does not sit well with many of Icann's overseas partners.
The question of who put Icann in charge is hotly contested.
Undertray or underbody
Lamb argues that "it's the online community; it's the people who've put Icann in charge". The European Commission wants changes to this system, though it still expresses its faith in Icann; the EU recently called for a "clear timeline for the globalisation of Icann". I have to admit I love the internet. It's a piece of engineering art you have to admire. And to be able to contribute to make this a safer place makes me feel good.
She admits she has two copies, in case she loses one; one of them never leaves a bank deposit box. The other, which she uses twice a year in the ceremonies on the east coast, is attached to a long metal chain. Most of the time it sits in a wooden puzzle box, with a hidden lock, created by her furniture designer son.
If dropped, or even knocked too hard, the machine will self-destruct. Now that everything has been removed from the safes, we move to act two of the ceremony: The first step would be familiar to anyone — getting the laptop plugged in and booting it up — but some witnesses watch like hawks, logging and initialising each step.
Others are beginning to flag, checking their watches or having whispered conversations with their neighbours.
The output of the previous ceremony is checked, to make sure people are working off the same key — a process that requires Arias to read aloud a character code. Everyone nods as they verify it against their sheets. Laurence Mathieu for the Guardian At Each keyholder hands over his individual smartcard. Alejandro Bolivar, an American expert from Verisign, the security company that administers the "root zone" of the domain name system, steps forward to read out a nonsense sequence of words generated by the previous key.
A short line of code is typed into the laptop at After a minute sequence of disconnecting secure machines and powering down the laptop, a USB stick is handed to Tomofumi Okubo, another Icann staffer. Deliberately or otherwise, Okubo makes a slight bow as he is passed the stick holding the "signed" digital key.
Undertray or Underbody
Later Okubo will transmit the key on a secure channel to Verisign and this signed key will be made live across the internet. It will take effect for three months, from 1 April yes, really.
After that, the key will expire and error messages will start to appear across the internet. Given how high the stakes are, and the number of possible targets, does Okubo think the system is trustworthy? Does this often slightly bizarre ceremony work? Are the security precautions integral, or just for show? Bruce Schneieran American cryptologist and security expert who worked with Glenn Greenwald and the Guardian to analyse some of the files leaked by Edward Snowdensuggests it's a little of both.
Not everyone present is entirely gripped. Lamb checks in to see how many people have been following the ceremony. The system admin calls back: The original said El Segundo was in northern Los Angeles, rather than the south-west of the city.