The drivers will use that full spread of the power at various times. While problems were anticipated with making this additional level of complexity work, in reality it turned out to be pretty straightforward. The bigger challenge was wear on the faces of the finger followers. Running higher revs called for a higher pressure in the pneumatic valve return system, producing high cam follower contact loads at low speeds, and it took several iterations in pre-season testing to overcome this problem.
Despite the higher return pressures, clearances are so tight that the valves will often mark the pistons during normal use, calling for a quarter degree or so adjustment in the timing to keep things safe. Since titanium aluminide was banned, Cosworth has resorted to a more common titanium alloy for the valves, with solid-stemmed inlets and hollow, sodium-filled exhausts for extra cooling.
The rods are titanium and, unlike some other manufacturers, still have separate shell bearings. Initially, the rev limit was reduced to ensure the life of the engines while the problem was tackled at the factory. The problem is ensuring the big end adopts the correct shape under load to achieve an even surface pressure across the bearing face with an uninterrupted film of oil.
Extensive work on the rod design, bearing specification and choice of engine oil allowed the full 20,rpm to be built up to again as the season progressed and confidence grew. This is indeed an impressive feat, when you consider that the piston has an equivalent mass of about 2. With peak gas loads greater than 65kN, and peak inertia loads verging on 60kN, there is little wonder the connecting rods can stretch as much as 0.
The location of the rod is entirely determined by the little end and the piston. To keep it in balance at 20,rpm the crank has balance weights made from Densamet, a tungsten alloy that is normally found on the end of missiles. Throughout the season, a large number of engine specifications had to be handled and extreme care was needed to ensure it was tackled efficiently. Without accurate tracking of parts and assembly procedures, reliability quickly deteriorates.
This is an area Cosworth has invested in heavily, developing bespoke software to help manage specification control and produce extensive build manuals for the engines. A big change between the TJ and CA engine projects was the knowledge the company had of the newer motor before it ran. A new engine project always brings its own set of unknowns as everything is being pushed so close to its limit. Then, with ever-increasing engine life mandated in the rules, further demands were placed on life critical components.
Even so, the TJ improved from to bhp per litre during its three-year life, while engine life increased from km to km. In contrast to the TJ, the CA passed its endurance test on its first outing, which pleased but did not altogether surprise the staff at Northampton because of the tools they had used to design it.
In the three years since the TJ was penned, Cosworth had done a great deal of work developing its simulation capacity. That it was achieved with a fraction of the resources and cost to the customer of the manufacturer engines in F1 is remarkable. Subscribe Newsletter. Your special offer X. Subscribe now. Home Articles Inside an F1 Engine. A peak output of around hp was typical, although the engines were restricted in their technology, rpm and lifespan.
As part of a reboot of F1 technology they were replaced with a totally new breed of engine. The current engine formula is in service until at least until While this might be a recipe for a return to the eighties high boost hp engines, the engine is instead capped by a fuel flow meter and the giddy heights of the mids 20,rpm V8s is kept at bay by the fuel flow limit and a max rev limit of just 15,rpm.
Allied to the combustion engine are two hybrid systems, one recovered kinetic energy of the car under braking ERS-K and another recovers the kinetic energy of the turbo charger, although in typical confusing F1 parlance, this is a heat recovery and the moniker applied is H for eat, so this is termed ERS-H.
In terms of power, the ERS system is capped at hp kw , so the V6 engine then produces nearly hp despite its lean fuel supply. The obvious way to make power with a race engine is to rev as high as possible, if not then run lots of boost. However, the PU rules were written to prevent just these sorts of techniques, by applying a fuel flow regulation.
For the manufacturers had to work out how to make the engine produce power with a paucity of fuel. Running lean means the engine is on the verge of knock, running too lean will eventually break the engine.
Most manufacturers played with legal additives to reduce this effect, one of which being Ferrocene, an iron-based compound that literally made the insides of the exhaust pipe look rust red. Mercedes, meanwhile, had found a little silver bullet: pre-chamber ignition. This is fine when there is enough fuel to mix in the right ratio throughout the combustion chamber. With this pre-chamber set up, the plug ignites the rich mix. With this pre-chamber technology Mercedes had the jump on the opposition in , it took time for their rivals to catch up and they have held the upper hand all the way to In terms of packaging the combustion engine, turbo and hybrid systems, there are two basic layouts.
Restricted by the basic architecture of the engine, only the freedom of the packaging of a single turbo above the engine and along its centreline was available. Although this did give some headaches for routing the cooling pipes from the compressor to the intercooler in the sidepod.
Wanting a compact intercooler installation of a front mounted turbo and the reduced thermal impact of a rear mounted turbo, they used both. The conventional turbo assembly is split, the hot exhaust driven turbine at the back of the engine and the cooler compressor at the front near the sidepods. This shaft would be the key reason for not taking this approach, the difference in speeding up and down of the two separate units, creates huge torsional loads in the connecting shaft.
This meant either the shaft was very stiff and heavy to transfer the loads. The route Mercedes took was to run a flexible shaft, the twist along its axis taking up the difference in the inertia of the two impellers.
Renault and Ferrari started and retained conventional rear mounted turbos, while Honda joined with a solution more like Mercedes, later developing into something much closer to the initial Mercedes split turbo design. Along with turbo placement, charge air cooling is split between the teams. As the turbo compressor pressurises the air, the air heats up. Teams will want cooler denser air going into the combustion chamber, so the air will need to pass through a heat exchanger to cool it.
For this an intercooler is used, two types are employed in F1. These peaked at around bhp. So for hybrid power units — PUs — to be surpassing those figures despite having internal combustion engines of only 1. At the heart of the matter is a 1. This is what most would still regard as a conventional racing engine: fuel in; mixed with air via a turbocharger spinning at up to ,rpm and ignited with a high-performance spark plug.
Revving to a capped 15, rpm way lower than the 20,rpm peaks of the 2. The remaining or-so bhp is produced by two electric motors attached to the ICE and working in harmony with it. The first of these is the so-called MGU-K — the kinetic energy recovery unit. Under braking, the motor-generator acts via a flywheel to generate electricity, which is then stored in a 20kg lithium-ion battery housed within the PU. The MGU-H is located between the turbine and compressor of the turbocharger, on top of the V6 engine.
This produces electricity, also stored in the battery. Under acceleration, the electricity is used in part to help eliminate turbo lag, by spinning the compressor in addition to the flow of exhaust gases over its blades.
Comparably powerful 3. Now, thanks to complex but deftly integrated hybrid technology and further gains in internal combustion efficiency, even greater outputs are being achieved from little more than half that fuel flow. Having joined the More importantly for the Sargeant only narrowly missed out on claiming the Formula
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