F1’S RULES SHOULD STRIVE FOR CLARITY
It’s not often that technical arguments are so long-lived in Formula 1, but this year two subjects have had a longevity beyond the norm. In the past disputes have been settled quickly or, at worst, brought before the FIA International Court of Appeal by way of a challenge to a decision of the stewards. The latter action involves a route that might take a little longer, but provides an authoritative finality to the matter.
The first of the two disputes concerned suspension. Before this season started, the FIA had decided to clamp down on the ever-growing complexities of suspension systems that were supposed to be passive. The genesis of this goes all the way back to 1993 when the FIA declared that the active suspension systems then in use were being designed with the primary purpose of augmenting the cars’ aerodynamic performance rather than providing insulation from the undulations of the track surface. As such, they could be considered moving aerodynamic devices, a concept embodied in the regulations and specifically disallowed.
The problem is that in any walk of life knowledge cannot be ‘un-learned’ and, very often, if the simple and logical route to a solution is removed for whatever reason, protagonists of the art will find an alternative that will undoubtedly be more complex. And so it was with these suspension systems. Initially the concentration was on complex hydraulic damper valving and relatively simple non-linear stiffness features that gave some additional platform control over and above that which had been employed by the teams in earlier years.
Later came a couple of interesting developments. The first was the tuned mass damper employed by Renault in 2005 and subsequently banned. This was a re-engineering of a very old concept. Around the same time, Malcolm Smith at Cambridge University conceived and developed a concept known as an inerter. This was an amazing piece of original thinking: a conventional damper provides a damping force that is proportional to the velocity of the suspension deflection, while in contrast the inerter provides an additional force that is proportional to the acceleration seen across the suspension. This may sound trivial, but it allowed control that had previously only been available with active suspensions.
The inerter is still commonplace in F1, but it had been supplemented with everincreasing complexities of hydraulic logic applied to the systems. The essence of these was to use the movement of the suspension to displace fluid through a series of orifices. The way these work is complex, but can be thought of as the conjoined double syringes you might use to dispense epoxy adhesives. If you squeeze these gently, equal volumes of hardener and resin are dispensed. Try to displace the plunger more rapidly and the more viscous resin will restrict the flow.
This is analogous to an actuator full of oil connected to the suspension with two flow paths out of it, one through a small orifice and one through a large one. If we displace the suspension slowly, as may happen when aerodynamic load compresses the suspension of an accelerating vehicle, then the flow out of the two orifices will be equal. Compress it more quickly, for example in a braking event, and the flow will favour the large orifice. If we now feed these two flows into a control valve we have countless possibilities to use this differential flow. An example might be to pilot an additional valve that might alter roll stiffness at one end of the car. It’s not an easy concept to explain, and nor does it lead to an easy system to implement, but if done successfully it can be pretty powerful in improving the performance of the vehicle.
These developments have led to four separate technical directives being issued this year by the FIA to restrict potential in this area and promote more simple
THE REAL TEST FOR FUTURE REGULATION IS FOR TECHNICAL EXCELLENCE TO BE UNDERSTANDABLE AND AVAILABLE RATHER THAN COMPLEX AND IRRELEVANT
and conventional suspensions. The introduction of these clarifications are thought to be part of the reason for the equalisation of performance between Ferrari and Mercedes in 2017.
The second long-running saga is that of oil burning. The modern Formula 1 engine is unusual in that its performance is limited by the amount of fuel introduced to it. For many years the limitation of race engine performance has been the breathing of the engine and hence the amount of air that can be introduced.
Now engine oil as we know it is not the ideal fuel for any engine, but formulating an oil that has certain volatile additives that either add chemical energy to the combustion process, or, more likely, limit the propensity for uncontrolled combustion, allows more power to be extracted.
Introducing this oil into the combustion chamber is a difficult process and it’s unlikely it is done by flow past the piston rings. Far more likely is that it is done by allowing oil-laden crankcase gases to enter the engine air inlet via the crankcase breather, or by allowing the controlled leakage of oil through the compressor side of the turbocharger bearing into the inlet tract. Either way, in a sport in which incremental improvement is the key to success, such small enhancements make all the difference.
Again, the FIA has taken a dim view of this line of development. It goes against the grain of putting a fuel-flow limit in place. Further technical directives have been issued to rein in the practice by limiting the oil that can be burned to an amount that may be considered reasonable for a racing engine. They further define what constitutes an oil, the primary purposes of which should be for lubrication and cooling.
The technicalities of these two disputed areas are unlikely to be of much interest to the majority of the sport’s fans. So it’s here that F1 must define its objectives. F1 sets itself apart from the plethora of controlled single-supply formulae by insisting that entrants be constructors and allowing technical excellence to be a performance differentiator. The real test for future regulation is to let this remain the case, but for technical excellence to be understandable and available rather than overly complex, irrelevant and in the custody of the secret society that F1 engineers are so keen to promote.
Mercedes and Ferrari have found complex solutions to the clampdown on supposedly passive suspension