Optimising Ganna: CFD, CdA, CORE & Bigham

The bike is only one part of the equation, we look at Ganna's CFD optimised aero position and some of the preparation work in breaking an Hour Record.

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Filippo Ganna is the new World Hour Record holder with a distance of 56.792 km. While much was made of the new Pinarello Bolide F HR 3D printed frame and fork that Ganna, and Dan Bigham before him, used for their successful Hour Record attempts, the rider is still the critical part of any bike ride. The rider is both the engine and the brains driving the bike, while the body is said to account for roughly 80% of total aerodynamic drag. As such, it’ll come as no surprise that Ineos Grenadiers spent considerable time and energy optimising Ganna himself for the attempt.

Understandably, the team will want to keep most of its competitive advantages under wraps. But there’s still a fair amount to be gleaned from careful inspection. Here is some of the new Hour Record tech we unearthed.

For even more, listen to our interview with the man who broke two hour records this year, Dan Bigham, on your favourite podcast app or right here:

CFD optimised aero position

Again, regardless of the latest and greatest bike tech, the rider will still account for roughly 80% of the aerodynamic drag on the bike and rider system. As such, optimising the aero position and kit can make or break any record attempt. Aero positions are hugely complex, though, and the fastest position or shape for one rider might be the slowest for another. As we have already seen, the helmet and handlebars that work best for Ganna do not suit Dan Bigham as well.

Wind tunnel and velodrome aero testing are highly valuable, but even then, it is difficult to know what positional tweaks to make and when. For example, a change in shoulder width or head height, as part of a bike fit, can change which helmet works best for that rider and undo any testing you have already done on helmets. As Dan Bigham explained in the second instalment of the Nerd Alert Podcast discussing the Hour Record, it’s difficult to know if an aerodynamic intervention is truly the optimal setup for that rider or just the locally optimised version of a sub-optimal setup.

It’s a minefield, and where to start seems as daunting as aero testing in general. That’s where Luca Oggiano of Nablaflow.io, 3D body scanning, and the Aerocloud computational fluid dynamic analysis software comes in for Ganna’s Hour Record. You might recognise Nablaflow and the Aerocloud software from our article on the new Pinarello Bolide F HR 3D bike Ganna used in his Hour Record. Pinarello used the software in developing the aerodynamic aspects of the new bike.

Luca Oggiano is the CEO and founder of Nablaflow and also the Principal Aerodynamicist with the Ineos Grenadiers. Using just a 3D scan of Filippo Ganna’s body, Oggiano could run countless aerodynamic simulations using Nablaflow’s Aerocloud CFD analysis, assessing a range of body positions, helmets, clothing options and how they interact with rider and bike. The learnings here fed into the actual bike design, and presumably vice versa, perhaps most notably on the flow control elbow/kinked risers we have seen on Ganna’s time trial bike throughout this season.

We often hear of CFD analysis and optimisation with new product launches, but this is a first for us when it comes to rider positions. Nablaflow’s website describes how Aerocloud “enables data-driven decisions” and “unlocks the true power of CFD by studying the flow fields and surface fields to gain deeper insight into the aerodynamic performance.”

Kinked risers on Ganna’s bars.

Simulations completed, the Ineos Grenadiers then validated the results with wind tunnel and velodrome testing to finally find the optimal position for Ganna. The CFD tools didn’t spit out a single exact position Ganna had to adopt, and even if it did Ineos staff had to factor in the human element of rider comfort and maintaining power production. But it did analyse an otherwise impossible number of positions. Of course, the position Aerocloud spits out has to be replicated on an actual bike with limited adjustability and defined shapes. That’s where 3D printing presumably comes into the equation, as we found out on a recent visit to Metron Additive Engineering.

Oggiano recently posted a video on the Time Trial Positions Facebook group demonstrating some of the analysis that went into Ganna’s position and explaining a similar service is available to anyone with access to a 3D scanner. We will have more detail on CFD-optimised time trial positions in an upcoming feature with Oggiano on the Aerocloud system, its capabilities and how it might influence bike position, design, and, ultimately, performance in the future.

Kask Aero Pro Visor

All that aero optimisation led to some focus on Ganna’s helmet. Kask has partnered with the Ineos Grenadiers since its inception as Team Sky over a decade ago, and the partners once again combined knowledge and new technology to develop a new helmet and visor for Ganna this season.

Most notable for its sharply angled edges, we first caught glimpses of the new visor at the Tour de France. At the time, the Ineos Grenadiers remained tight-lipped on the exact benefits of the new visor design, with many speculating it helped in directing the airflow off the helmet. CyclingTips spoke with Marco Galli, Cycling Marketing Manager with Kask, about the new visor immediately after Filippo Ganna’s successful Hour Record on Saturday evening.

Galli explained the new visor project began back in January, with Kask engineers developing the new visor in partnership with the Ineos Grenadiers and through a series of wind tunnel and CFD tests to find the ideal aero shape. As suspected, the visor is designed to deflect the airflow off the helmet and around the rider’s shoulders and is seemingly another example of the holistic approach to aerodynamics evident across Ganna’s bike, made possible by Nablaflow’s AErocloud CFD analysis mentioned above. Such increased understanding and analysis capabilities mean teams and manufacturers can now understand and develop new designs which, when tested in isolation, seemingly increase aero drag, but when added to the rider and bike as a complete system, can help to reduce total aero drag.

The designers faced challenges in integrating the polycarbonate aero sides into a lens while retaining the optical clarity and safety standards Kask targets, Galli went on to explain. “There’s just one objective: to reduce the cyclist’s aerodynamic drag, and for the new Aero Pro visor, following six months of hard work, we’re able to offer a product that we believe will be a fantastic ally for any athlete,” said Luca Viano, Product Director at Kask.

Kask claims the visor is “guaranteed to enhance aerodynamic performance” of the helmet by as much as 6%, although, as already mentioned, aerodynamics are quite individual, and what works for one rider, might not for another. 

While Ganna set a new Hour Record wearing the Bambino Pro Evo helmet, the new visor is also compatible with the Bambino Pro, Mistral, and Mistral LW. The Aero Pro visor is available now priced at €140 for the clear and €160 with a mirror finish.

3D scanned head and matching helmet

The Kask Bambino Pro Evo helmet itself is also designed specifically for Filippo Ganna. Not in terms of aero-optimised shapes or prototype designs as we might expect, but internally the helmet is sculpted to perfectly fit Ganna’s head. 3D scanning played a part once again, as Kask scanned Ganna’s head.

Externally, Ganna was treated to an Italian Tricolore custom colourway, which is surely worth more than a few moral boosting watts.

Body temperature is crucial

When we exercise, we get hot. When someone attempts an Hour Record in a stifling hot velodrome, getting hot can very quickly turn into getting cooked from the inside out. Increasing core body temperature will inevitably result in decreasing performance and the Ineos Grenadiers, like almost every athlete in the World Tour, identified understanding and managing core body temperature as key to a successful Hour Record attempt.

The little white sensor attached to Ganna’s heart rate strap has become a common sight beneath the jerseys of World Tour athletes up and down the peloton over the last 18 months or so. We delved into the metric and the sensor in much more detail in an article published ahead of last year’s Olympic Games, so won’t do so here again. Instead, we will look specifically at what the Ineos Grenadiers learned from the CORE data in preparation for the event. Ineos had both Ganna and Bigham wear the CORE sensor in both training and during the attempts, but in speaking to CORE, we understand it is most valuable in training.

Ineos identified a 1°C increase in core temperature results in a 1% drop in gross efficiency, the ratio of thermal energy to mechanical energy. A 1% drop in gross efficiency could be as much as 15-18 watts during an Hour Record, or in other words, the difference between a successful attempt and a failed attempt. Core body temperatures could easily hit 40°C or higher during an Hour Record in a heated velodrome with intense efforts and a long sleeve skinsuit.

Ineos used the CORE sensor to understand both rider’s thermal physiology and implement pre-cooling and environmental strategies to mitigate the increase in core body temperature during the Hour. These strategies were as simple as drinking ice slushies pre-ride, to slightly stranger interventions such as indoor training in two painter’s suits. Bigham also confirmed on this week’s Nerd Alert that the Grenadiers had, in fact, planned to roll out some industrial-sized dehumidifiers to decrease the humidity within the velodrome had the weather not played ball for Ganna’s attempt.

The CORE sensor was also used to develop effective pre-cooling strategies, including the aforementioned ice slushies, the commonly used ice vests pro riders now warm up in and even ice cubes of their preferred pre-ride drinks intended to literally cool their core. They also had helmets stored in the freezer.

The Ineos Grenadiers and CORE published this Instagram video in the lead-up to Ganna’s Hour record detailing some of the insight the CORE sensor provided. That video has also proved quite useful in identifying some other interventions Ineos made for the Hour Record attempts.

As seen during the recent Time Trial World Championships, the video also shows Ganna testing out an aero base layer with “trip strip” ribs on the sleeves designed to interact with the thin fabrics on the skinsuit sleeves to improve the aerodynamic efficiency of the arms. While on the ground we noticed Ganna wearing these rather warm-looking aero overshoes.

Dan Bigham estimated his aero-optimised Nimbl shoes could have given him as much as 100m in his successful Hour Record ride. CyclingTips understands Ganna had prototype shoes available to him but instead opted to stick with his tried and tested Northwave Extreme Pro II shoes he has used throughout the season.

While we didn’t see for ourselves as the shoes remained hidden beneath these Bioracer overshoes, the visible outline of the shoes certainly matches the shape of the Extreme Pro II shoes. Those overshoes are also familiar to Ganna, and, at least to our eyes, appear identical to those which Ganna has used on the road throughout the season and those which Bigham used for his Hour Record. That said, the aero overshoes do not yet appear on the Bioracer website, suggesting they could still be a prototype in development with the Ineos Grenadiers.

Bioracer provided the skinsuit, which was notably different from the Bioracer suit Dan Bigham used for his successful Hour Record attempt. Ganna’s version had an altered neck collar and a front zipper versus a rear zipper.

Speaking with CyclingTips during the Hour Record attempt, Sacha Sochacki of Bioracer explained some of the classic designs Ganna wanted to incorporate into his custom skinsuit. Looking more closely at the performance aspects of the suit, Bioracer explained the development of this third-generation suit started right at the outset of the brand’s partnership with the Ineos Grenadiers.

The suit is tailor-made to fit Ganna perfectly in his time trial position, and together with compression incorporated into the suit helps Ganna maintain that position throughout the Hour. Four-way stretch fabrics are used throughout the suit to improve comfortable and aero fit, which also helps reduce drag-inducing wrinkles.

The suit also features taped seams, said to significantly reduce drag and improve fit compared to more traditional seams. Lastly, Bioracer says it tested a range of fabrics to find the fastest option for each part of the body, with some fabrics said to increase aero drag by up to 70% compared to the optimal fabric when wind tunnel tested on cylinders.

Aero sensors

Last, but by no means least, the video published by the Ineos Grenadiers also appears to show some aero-testing technology many of us are excited to hear more about. First up is the Forma body position sensor from Streamlines Aero. The Forma mounts to the stem and uses range-sensing technology to measure and record the rider’s chest, head, and waist positions throughout a ride. Presumably, the Ineos Grenadiers used the Forma to assess how well Ganna could maintain the aero position in pre-Hour test rides.

Next up is what appears to be the long-awaited aero sensor from SwissSide. The Aeropod has been in development since it was initially used for collecting real-world data on the Kona triathlon course. Little is known about the Swiss Side aero meter, but presumably, it served as part of the validation testing following the Aerocloud CFD simulations, and it is exciting to see it in use at the highest level again.

Some images of Swiss Side’s Aeropod on its website show a twin probe device mounted between the aero bars. Ganna can be seen using a similar device in the video published last week. We have contacted Swiss Side for more information on the Aeropod, hopefully, we will see it available to the public soon.

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