When you are in the horror traffic of Mexico City, the last thing you think of is that you are at the same altitude, above sea level, as the Passo Sella in the Dolomites. And yet it is so: and this weekend’s Grand Prix has always been accompanied by learned disquisitions on the rarefaction of the air and on the problems that this entails. It is not only the aerodynamic appendages that are short of breath at high altitude: even the turbocharger blades, having to grind less dense air than usual, blend like crazy. And how do you slow them down, to stay within the regulatory limits of 125,000 rpm and to avoid breaking everything? A good method is to use it MGU-H, that is the motor-generator unit integral with the turbo shaft, to produce current and therefore – a bit like eddy-current banks – to contain the excesses of the compressor. Even on the straight, if necessary.
This – which platoons of engineers are certainly preparing to comment on – is one of the uses of the infamous ‘Acca’: as well as one of the rare occasions in which this component of modern Power Units is mentioned to the general public: thus remembering that it exists. Just yesterday I was having lunch with a little-known but very authoritative engineer, both in the F1 and supercar field, who commented on how the MGU-H was, in his opinion, a useless technical exercise: it weighs like a boulder, produces relatively little energy and comes with a lot of complications. Yet even now that its future in F1 is in question, there are those among the manufacturers of four-wheeled toys for bored billionaires who would like to incorporate it into those dream road car projects that cost as much as the GDP of ‘ Honduras and will allow the lucky buyer to travel at over four hundred kilometers per hour. We do not know where, and above all why.
To be honest, the heat engine was in danger of disappearing shortly after birth. In the early days of his presidency, Sergio Marchionne had left in a hurry to demolish the plant wanted by Jean Todt (with the approval of the great manufacturers, including Ferrari) and bring F1 back to a slightly less spatial dimension. In the corridors of the Geneva meetings there was talk of aspirated or single-turbo motors, the return of supplies during the race and other amenities. All ideas that would have turned back the technological clock, but also forced the designers to do it all over again, with the costs that this entails and decreeing in advance the end of the ‘green’ project of the FIA president. What then, to evaluate the quality – and not the quantity – of emissions, it is green so to speak, but patience.
In fact, in the face of the interest shown by new realities, an alternative formula has been evaluated for some time. And it will almost certainly be our friend H. whose main function, one might say, has always been that of technological showcase: the efficiency – truly incredible – of modern F1 cars, which with a hundred kilos of fuel or a little more travel over 300 km of a Grand Prix, could not benefit only from the recovery of kinetic energy under braking like any Prius. We needed a gadget capable of transforming even the heat of the exhaust gases into energy. Which, in its own way, also makes a simple turbo, known for over a century in the mechanical industry (although many people believe that Renault invented it in the mid-1970s).
The way, already indicated, is to strengthen the other generator, the one that recovers energy during braking and converts it into electricity to be sent, when needed, directly to the transmission. That is the famous MGU-K, born as Kers as early as 2009 as a mechanism of dubious utility, with its sixty Kilowatts that can be expressed for a few seconds, and then doubled in power with the advent of Power Units. Much more can be done with relatively little effort, thus helping to keep the weight / power ratio of these increasingly “plus size” F1 cars within interesting limits. To be honest, even more could have been done with the MGU-H, potentially able – rules permitting – to “drive” a car all along the circuit. But this, of course, would have triggered a spiral of costs and developments that would soon spiral out of control.
Now there Porsche knocks again on the doors of F1 and it is a sincere and planned interest. After a fleeting appearance in the 1960s and a marketing masterpiece to the contrary twenty years later, when it became “the Tag engine” for everyone, the Germans had reappeared, thirty years ago, with an unnecessarily bulky and complicated V12, destined to the equally incongruous Footwork of Alboreto and Caffi. Now, they tell me, there is an articulated plan. No one can say now whether Weissach’s power unit will be competitive this time. However, in terms of speed, for now the project has beaten the regulations for which it is intended.
#understood #FormulaPassionit