There's a fair chance you haven't heard about Elemental. A new kid on the track day block, Elemental is yet another small British manufacturer that wants to make it big with its cleverly engineered but emaciated and not conventionally handsome, Time Attack weapon. Except this one is a bit different. As Mark Fowler puts it, "Most of the people in our company are either ex-F1 designers or major manufacturer designers, so we're all highly skilled, and I don't think any of our competitors has that sort of pedigree."
The best proof for these words is Mark himself. Having worked as an aerodynamicist in Formula 1 for 15 years, he decided to leave the motorsport industry in 2012 and team up with another British chap named John Begley to create a car design that both had been thinking of for a long time. That's how the Elemental brand was born, which quickly gave birth to its first car, the Rp1. While not exactly a looker, it quickly gained attention thanks to its superior driving dynamics, achieved mostly by its atypical powertrain layout. The Rp1's engine and gearbox mounted longitudinally F1-style, as opposed to most cars in this class that rely on the transverse powertrain of a FWD car, relocated to back end. This allows for the use of a bigger diffuser and tapering of the body behind the cockpit, for superior aerodynamics. In the fall of 2016, the company delivered the first car to its client, but Mark's job was far from finished. The company has just released an aero package for Rp1, which upgrades the stock downforce level of 882 pounds to the headline-grabbing 1,000 kg (2,204 pounds) at 150 mph. As its creators hope, Rp1's new body will enable it to set the Nurburgring Nordschleife production car lap record. This would mean throwing down the gauntlet to such track celebrities as Porsche 918, Dodge Viper SRT-10 ACR, and the current record holder, Radical SR8 LM.
While still some way off the unthinkable aerodynamic levels achieved in Formula 1, Elemental's 2,204 pounds of downforce is poles apart from anything else wearing a license plate. To put it into context, one of the most aerodynamically advanced cars in recent history, the McLaren P1, manages 1,323 pounds of downforce at 161 mph. The radical Viper SRT-10 ACR, with its wings, spoilers, and a horribly compromised drag coefficient of 0.54, creates around 1,700 pounds at its very peak. And the best part is that this rather spectacular feat by Elemental happened by accident.
In a very cliched British manner, it came to life in a local pub over a pint of beer. This is where guys from Elemental met with Mark Taylor, another ex-F1 aerodynamicist, who left McLaren Racing early 2016 to open his own computational fluid dynamics consultancy studio called London Computational Solutions. As Mark T. reveals, "I was just starting my new company and the guys asked me to look at the Rp1 and tell them what I thought about its aerodynamics. After a week, I came back with an answer that there's a huge potential in the car and I'd love the opportunity to deliver that. They replied, 'Yes, please!' and the result is the aero upgrade you see now."
While still of limited use even in the performance car segment, CFD simulations that are the spiritus movens of the F1 game turn out to be a perfect suit for a specialized company like Elemental: "At McLaren Racing, we were trying to develop aerodynamic ideas quicker than any of our competitors, and soon we advanced to a point where in many cases we didn't need to go through the expensive and time-consuming process of building wind tunnel models," Mark says, pointing out that "it's a perfect solution for a company like Elemental, which wants to evaluate various scenarios and progress quickly." Mark is talking about his company, not CFD in general: "It's crucial that the technology that we're using is accurate so you can trust the numbers that it gives you. We're using a novel technology that I'd worked with Imperial College in London to develop over the last decade and that resolves turbulence rather than models turbulence [see sidebar]. This gives us a much more accurate picture, and when we build the car, we can be confident it'll have this kind of downforce that we predicted." Before the competitors get too excited, Elemental's Mark Fowler is quick to point out that this level of aero performance was possible only because Rp1 was like that from the beginning, "We always wanted it to be an aero car, and with the core model done this way, we could develop it in the way Mark Taylor resolved it."
But isn't a ton (literally) of downforce too much of a good thing? There are a few reasons for which not many cars reach this kind of downforce, other than engineering limits, and virtually all of Rp1's direct competitors prefer to base their performance on the mechanical grip. Highly advanced aerodynamics often don't work the way they're supposed to in varying weather conditions and on uneven surfaces, and even if they do, most of the drivers aren't skilled enough to fully exploit them, as the car would need to go really fast to get the aero package actually working. Not so with the Rp1, Mark Taylor claims, "It being a road car, or a track car that any person can drive, we were very careful to get the downforce stable and perform at a wide range of speeds. What happens typically is that the stability of the flow features of the car changes with speed. This can make a car quite difficult to drive. In the case of Elemental, though, when you're going on a track, you're typically driving at lower ride heights (you can adjust the height of the front suspension by a flick of a button), you get stronger aerodynamics, and when you're on the road, you're going at more sensible speeds, which lets the car have a higher ride height and makes for well-behaved aerodynamics. At corner entry, you get a stable rear; mid-corner, you get good rotation and then strong rear again to give you traction exiting. We're not trying to create a car that only a professional can drive; it's a car for people to really enjoy."
After all, Mark Fowler, the creator of the primary design, is adamant that the new aero package has not changed the characteristics of the car, but, let's say, turned it up to 11: "The base car had a considerable amount of downforce already, so it's a major step up, but it's pretty much a similarly behaving car. Obviously, we had to look at the mechanicals of the car because we've got this extra loading on the four corners now. It wasn't really a big deal, though; these were things we would do anyway. You need to remember how light the car is; mechanically, it is only about 1,200 pounds, so even if we put 1,000 kilos of downforce, it's still lighter than a Volkswagen Golf. It's not like we're doing anything outrageous. The package won't even affect top speed much, as the car was perceived around the ground effect, which gives you more downforce for less drag (compared to wings or spoilers)."
Being a simple man, I admit that the sight of such a huge rear wing would quickly make me think of throwing an even more powerful engine into the mix than the Ford Focus ST-sourced 2.0L Ecoboost I4, here tuned to produce a still relatively modest 320 hp. To fuel our imaginations, Mark Fowler admits that an engine swap is a simple operation in this case: "From the mechanical layout standpoint, there's enough scope to put other engines in. We're not looking at it just yet, but we have the will to think about that in the future. The current 2.0L engine could be tweaked a little bit more. We've got no issues with the power as it is now; it's pretty fast and powerful as it is." Taking into consideration that it's already expected to set a new record at the Nordschleife, it surely is. As in a Hitchcock movie, the guys at Elemental started from an earthquake and from there, the tension only rises. It'll be interesting to watch their act.
The feature mentions "resolving" instead of "modeling" turbulence. Turbulent flow is defined as flow in which the fluid undergoes irregular fluctuations or mixing. This is opposed to what is called laminar flow, which moves either uniformly or in layers. Even with today's easily accessible computing power, we have to make some assumptions about what is happening in flow simulations. We look at flow on a larger scale, more in terms of space divided into individual cells looking at conditions within individual cells rather than the actual path of the fluid. In most Computational Fluid Dynamics models, we wouldn't simulate individual eddies or vortices, instead, we would look at the pressure in the cross section where we know turbulent flow would exist. This leads to inaccuracies in some instances as well as whole gaps in knowledge if any of the conditions of the simulation are changed, i.e. velocity, crosswind, even ambient temperature or change in ride height. If we take the time to resolve the turbulence, we are calculating the eddy currents and velocities, so that one model can be applied to varied conditions. —Febbo