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Red Bull RB18
Paul Monaghan, chief engineer of the RB18
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The familiar sight to spectators of F1 in 2022, a Red Bull Racing RB18 taking the chequered fl ag
Of the 2022 F1 contenders, Red Bull Racing appeared to have the best overall package. Racecar talks to the team about the RB18’s development, and the effect of its recent budget cap penalty
By STEWART MITCHELL AND DIETER RENCKEN
The Red Bull RB18, Red Bull Racing’s response to a set of radically new technical regulations for 2022, proved insuperable in the first season of F1’s new era. The team sealed the 2022 Formula 1 Constructors’ Championship as Max Verstappen won the United States Grand Prix in Austin, the 19th round of the 24-round season.
The Constructors’ title, paired with Verstappen’s second successive Drivers’ Championship, is Red Bull’s first since 2013 and ends an eight-year streak of domination by German manufacturer, Mercedes.
The RB18 finished the 2022 season as one of the most successful cars to date in F1, taking the chequered flag at 17 races in total – 15 for Verstappen and two for Sergio Perez.
The RB18’s concept stood out from the outset at Barcelona testing in February 2022, featuring some unique design elements, including the extended lower lip of the sidepod intake openings and the swept back rear leg on the front suspension. However, it was the car’s well-behaved driving manner that caused the most interest when it seemed to suffer significantly less from so-called porpoising than many of its rivals. This smooth introduction to F1’s new era saw it at the sharp end of the grid from there on out.
Development path
Despite Red Bull’s 2022 success, the realisation of the RB18 could certainly have been smoother sailing for the Milton Keynes, UK-based outfit. The team was forced to pull resources from the 2022 project in the latter stages of 2021 as the season came down to a shootout with Mercedes in the later races. Therefore, the personnel, wind tunnel, CFD and design resources that would have otherwise been directed toward the 2022 car remained on the 2021 RB16B, right up until the very last lap of that season.
‘The 2021 campaign dramatically affected our 2022 car development,’ Paul Monaghan, chief engineer of the RB18, freely admits. ‘With much of our capacity staying on the RB16B for longer than we had readily planned, the severe regulation changes for 2022 and finite resources we had remaining, we were worried we had damaged the development of the 2022 car going into the start of the season.
‘That said, the RB18 proved to be the ‘least-worst’ car on the 2022 grid, the result of hard work, research, design, manufacturing, and realisation of our business with our available resources. We were at least as efficient as anybody else, and we had a great car from the outset.’
As for the RB18’s overall concept, Monaghan explains: ‘During our development of the 2022 car, we looked at the results from our initial CFD tests and made a judgement on how best to operate a ground-effect car at all the circuits. We took our design route early in the development process and stuck with it to exploit the potential of the road we chose.
‘The main thing was getting our heads around the car’s aerodynamic demands. In terms of how you operate it relative to the ground, it is quite different to the 2021 and preceding cars. We knew we would run lower rear ride heights compared to the last regulation set, so the travel at the rear axle compared to the front would be significantly less. But that reduced rear travel has compliance benefits.
‘As such, in the 2022 regime, if you’re making high aerodynamic loads on the straight, the heave stiffness must be higher than it would otherwise have been for a 2021 car. This forces your hand in some elements and forces you to carefully design for the desired compliance.’
The Newey effect
One of the few people in F1 with significant experience with ground-effect aerodynamics is Red Bull Racing’s chief technical officer, Adrian Newey. In fact, Newey wrote his university thesis on just that subject, and his first job was chief aerodynamicist at Fittipaldi Automotive, working on the 1980 F8, itself a ground-effect car.
He would go on to design the March 82G GTP, which featured a significant hole between the front fenders that fed air to massive underbody tunnels to generate ground effect. The March 82G won two IMSA GTP titles and saw two further evolutions, namely 83G and 84G trim. This experience with ground-effect cars from early on in his career made him aware of some of the possible hazards lying in wait with F1 2022’s car with its ground-effect underbody.
Despite Newey’s extensive experience in the field, he only fed into the Red Bull technical group that created the RB18, and his design input was limited to the suspension. Nevertheless, the suspension is a critical part of the car’s platform control, and arguably the most significant contributor to a groundeffect car’s performance.
Monaghan explains: ‘Suspension proved to be the most sensitive area of the 2022 car, given that the FIA had simplified its technology with the introduction of the latest regulations and ride height control.
The RB18’s front wing features a separate lower element to control the flow field entering the car’s ground-effect floor. Understanding this complex interaction helped to control any porpoising
The larger brake package for 2022 was a significant contributor to the initially high overall weight of the RB18
This coincides with developing the suspension stiffnesses, which is paramount in this new regime.’
To put that statement into context, for 2022 the FIA changed the suspension system regulations, banning any inerters, mass dampers or acceleration-sensitive valves in the dampers, thereby prohibiting any systems or configurations that change the response of the suspension elements to body accelerations and / or angular acceleration of the rockers.
Suspension systems
‘If you want to run the car lower to the ground, you must raise the suspension stiffnesses, which can have severe compliance side effects,’ Monaghan continues. ‘Ride height was the element of the set-up that received the most attention in 2022, but it does not come in isolation. As such, one part of the ride height vs suspension stiffness set-up wasn’t dominant over another. These cars are sensitive, so you cannot change one aspect without manipulating another.
‘The aerodynamic operation is the most critical to the fastest lap time. Still, if you get the complementary functions wrong, you will be punished by things like porpoising and driveability issues.’
The RB18 features a pull rod front suspension which allows for a lower installation for the suspension mechanisms, aiding a more dynamic, lower c of g, frontend capability. It also allows the rearward- moving flow field path to the ground effect venturi throat to be kept cleaner, free of any disturbance that might induce unwanted turbulent flow into the floor’s venturi.
Moreover, because the pull rod concept is a second-class lever system, its characteristics are softer than the pushrod’s first-class lever system, aiding compliance between the unsprung and sprung masses when there is a significant displacement between them.
However, when the front lowers at speed, the characteristics of the second-class lever system stiffen as it is a rising spring rate, which supports the platform as aerodynamic loads are introduced to the car’s inputs. This design is likely part of why Red Bull has suffered significantly less from porpoising than its rivals throughout the 2022 season. The multi-link arrangement of the front suspension sees the trailing wishbone swept back and intersecting with the chassis significantly further down than the front one. This design was implemented as an anti-dive measure. Anti-dive geometry diverts the forces transmitted under high aerodynamic and braking loads away from the springs and dampers and through the suspension links to minimise disruption to ride height, limiting the rear ride height increase and the downforce loss it entails during braking.
This multi-link system sees the mechanical elements of the suspension needing to be made stiffer, and therefore heavier, than a more conventional wishbone suspension design. As proven, the benefit of platform control and compliance outweighed the weight deficit.
At the rear, the pushrod arrangement was perceived to provide stiffer and lighter mechanical installation to preserve the platform control needed to support the ground-effect aerodynamic regime. Additionally, the pushrod concept allowed tighter packaging of the suspension, keeping it free from encroaching on the diffuser exit, which aids the efficiency of the ground-effect floor and the rear beam wing interaction.
The RB18’s long rear suspension travel accommodates a variety of ride heights, allowing it to ride low at high speed, reducing drag. Despite it having a greater static ride height than much of the grid, the long rear travel, combined with a relatively soft spring rate, meant the car could settle low in such a way as to enable high straight-line speed compared to the competition.
Red Bull Racing’s chief engineer, Paul Monaghan, and chief technical officer, Adrian Newey (in cap), inspect the RB18’s floor
Floor design
Red Bull Racing took a different approach to the design of the RB18’s floor. Most of the cars on the 2022 grid feature a teardropshaped central section between the tunnels, providing a smooth, continuous surface on
Red Bull’s pull rod front suspension is a second-class lever system, its characteristics softer than the pushrod’s first-class lever system, aiding compliance between the unsprung and sprung masses
the inside of each tunnel from the intake to the diffuser exit. This coincides with a consistent throat and diffuser ceiling angle into and out of the venturi point, respectively.
In contrast, the centre section of the RB18’s floor features a number of stepped elements on its outer wall (inside wall of the tunnels) and the roof of the tunnels also appear deeper, narrower and more sculpted in some sections along its length. The step changes of the central section, along with the varying profile to the height of the tunnels, is likely an effort to keep the tunnel volume consistent along its length to provide a steady mass flow from intake to diffuser.
‘There are multiple aspects of the floor that are weighted differently, depending on how you want to extract performance,’ explains Pierre Waché, technical director of Red Bull Racing. ‘You can be aggressive with the floor design, but you then narrow the window within which it works most effectively. Where you put the main load on the floor, which is around the centre of pressure of the venturi section, affects the overall concept of the car in terms of load distribution and aero balance.
‘The main aspect of this year’s car was the development of this, and the rest of the components were associated with that.’
The RB18’s floor design seemingly provides higher resistance to stalling the underfloor flow, compared to a floor with a consistent throat and diffuser ceiling angle into and out of the venturi point. In theory, Red Bull’s design should enable softer suspension to work to maintain grip and compliance between the tyre and the track, with the ability to engineering the set-up to manage weight transfer where necessary.
With a stable underfloor aerodynamic regime, Red Bull could potentially decouple some of the influence of the floor on the suspension, combining the wheel travel frequency, damping ratio and weight transfer for the best spring and damper set-up for the track, which can then be optimised for the conditions more readily than its competitors.
Red Bull went on to use a variety of inlet vane and floor edge arrangements to tune the car to individual circuits throughout the season. Changing these elements alters the aerodynamic centre of pressure acting upon the front and rear axles, adjusting the aerodynamic balance of the car. This suggests the team had a very high-fidelity control of its underfloor airflow.
The result was the RB18 struggling far less with porpoising than many others in the field, and the combination of floor and suspension design is likely the largest contributing factor.
Weight loss
Perhaps the most significant development of the RB18, though, has been its ongoing weight reduction programme. The car began the year 20kg over the minimum weight limit of 798kg, and a number of significant elements contributed to that.
‘The cost cap influenced everything on the RB18, but it was most influential when it came to the weight,’ notes Waché. ‘Compared to what we used in the past, plenty of parts are compromised compared to what you might do if there was no financial constraint. The resulting component is not necessarily compromised in terms of performance, but questioned in much more detail than they were before the cost cap was implemented.
‘With the cost cap in place, you must extend the life of parts, which typically sees them designed to be more robust and heavier, to make it economically effective and last longer. Sometimes we choose a material that is cheaper, which is typically heavier as well. Sometimes you don’t do development because the performance gain is not there at the cost it requires, and this balance is a big part of Formula 1 now.’
The aerodynamic loads generated by the powerful floors mean they must be stiffer, and consequently heavier, than the previous generation of cars to remain rigid. The newfor-2022 18in tyres and bigger brakes are also much heavier than the previous generation.
Unlike the previous generation of cars that relied primarily on the outer surfaces of the car for aerodynamic gains, the floor is now the primary aerodynamic load generating part. As such, the tight Coke bottle shapes of the previous generation cars is less prominent now
A lot of the car’s excess weight was originally toward the front, which gave the early version more understeer and made it prone to front brake locking. The weight came off via a series of upgrades throughout the season, including a new floor at Imola, re-designed brakes and the hollowing out of some components that had originally been manufactured as solid because of time constraints in the design phase. Gradually, the weight distribution moved towards the rear. This coincided with an accompanying rearward shift in the aero balance, giving greater rear stability on corner entry without affecting the initial direction change.
‘In terms of making the weight savings, there are only so many areas of the car that can be addressed to bring the weight down to the level that would make us competitive,’ Waché notes. ‘There were some ancillary components that were designed conservatively and heavier and they were easy to work on to save weight. However, this was not the goal for the start of the season.
‘Our strategy was to replace parts for mileage and put lighter ones on when we could. This was the best way to control the costs. There are some parts of the car, especially the floor, that we deliberately made heavier for reliability reasons. We knew it needed to be robust to prevent destroying it on the kerbs and so on.
‘When we saw the car in operation for the first time, it gave us the data we needed to start developing a new, lighter version. That was an easy opportunity to reduce weight.’
Blown budget
It is not all roses in the Red Bull Racing camp, though, as it has been found to have breached the cost cap regulations for the 2021 season, the first year of its implementation. Over the 2022 Mexican GP weekend, Formula 1 finally confirmed the team’s penalty, hitting it with a $7 million fine and a 10 per cent reduction of its aerodynamic testing allowance for the next 12 months. The FIA adjusted the strength of the penalty after its initial £1.8m overspend was amended to just over £400,000 after a tax credit had been correctly applied.
Despite this, many of its competitors are of the opinion that Red Bull has got away lightly, and the integrity of Formula 1’s budget cap has been in jeopardy throughout this process. There are many critics of the result of Red Bull’s breaching the cost cap regulations, especially as a $7 million fine is small beer for a company of Red Bull’s size. Moreover, it does not come out of its present or future cost cap, it must be settled separately.
Reducing Red Bull’s budget cap in the future somehow wasn’t an option available to the FIA under the terms of an accepted breach agreement.
The more significant damage to the team is the reduced aerodynamic testing element of the penalty, which impacts its CFD and wind tunnel programmes. This penalty is the equivalent of 1.5 finishing positions in the Constructors’ Championship, associated with the diminishing testing scale as a function of the team’s place in the championship when wind tunnel allocations are determined.
Formula 1’s new handicap system means successful teams already have less aero testing allowance than those finishing lower down. The team finishing last is given a 115 per cent baseline allowance, dropping by five per cent for each position until the winning constructor is given 70 per cent of the nominal amount within its aerodynamic testing period, of which there are six per year, each lasting around eight weeks.
Because Red Bull won the 2022 Constructors’ Championship, the development allowance would see it entitled to 70 per cent of the baseline limit for 2023. This amounts to 224 wind tunnel runs and 1400 CFD items per period. That is 16 fewer wind tunnel runs than the next highestplaced team, and 32 fewer than the third.
In CFD terms, it represents 100 fewer components than the second-place team, and 200 fewer than the third. However, because Red Bull’s penalty for breaking the budget reduces this by a further 10 per cent, it now has a reduction of 22 wind tunnel runs and 140 CFD items per period, equating to 38 fewer wind tunnel runs, and 240 fewer CFD runs during each period compared to the second-place team.
Red Bull’s testing limitation lasts for 12 months from the execution of the accepted breach agreement, October 26 2022. The penalty will impact whatever development work the team completes in the final part of 2022 and 2023 car development until the same date in October next year, which will affect both the in-season development of the 2023 car, and the 2024 one that follows.
Red Bull indicates the effect of the penalties could be worth anywhere between 0.25 and 0.5 seconds of lap time.
‘With the limited testing allocation that we must work to from the penalty, we don’t want to burn resources on the wrong things,’ says Monaghan. ‘The car for next year will be similar because the regulations are similar, but we are using the resources we have now to develop the car in the most efficient way.
‘The wind tunnel and CFD testing deficit are connected. These are our main tools of development. The rules are set up to somewhat balance the performance of the teams across the grid as a function of the handicap associated with aerodynamic development. This system is very effective and will have a significant impact on us for next year, and the grid over the years.
‘It is very difficult to offset this handicap. We have some of the best F1 engineers in the world, but the other teams also have very effective members of their teams. We can work harder, but the others will be, too.
‘What is true is we will have to be more efficient with the resources if we are going to make up for the deficit.’
