F1 2016: Rules and Trends

With the 2016 car launches just days away, let’s look at some of the likely changes and trends to keep an eye out for as launches and testing continue

RULES

Cockpit padding and impact test

cockpitpadding

A small nod to increased safety is the change in the side padding for the cockpit. The area now has a load test to pass and the padding has a minimum surface area rule to be applied. Visually this should make little difference, but the area to the side of the padding is often used as a cooling outlet, so teams may need to reconsider their cooling set up if the tub needs more structure and width in this area.

FIA HSS camera

FIA-HSS-Cam

A rear facing high speed camera will now face the driver, in front of the front roll hoop fin. This camera has its own logger and constantly records with a high frame rate. In the event of a crash the images are kept and the FIA can review the effects on the driver and especially their head during the accident. In order to better under the mechanisms involved in crashes

Mickey Mouse Exhausts

Merc_rear

The only real technical rule change is the switch in the exhausts. Now the turbo wastegates must exit into one or two tailpipes separate from the main tail pipe. This should increase the loudness by unto 25% as the muffling effect of the closed pipes from the wastegates joining the main tailpipe, used to muffle the noise from the turbo. F1 wastegates rarely open, as this is inefficient, the MGU-H does the same task and recovers energy whilst doing so. We should not expect any change in the pop and bangs emerging from the car, nor any streaks of flame when the wastegates do open.
This leaves the team with the packaging issue of the tailpipe. They can run one or two pipes and they have to exit in the same area as the main tail pipe, no rerouting for clever blown effects and as previously detailed no scope for operating fluidic switches.

Merc_rear-LOWER2

I’m told a common route is the mickey mouse set up, where the two smaller wastegate pipes exit above\below the main central tail pipe, creating the mouse eared shape.

Merc_rear_STACKED

I expect the teams would prefer a single pipe for less blockage and easier rear wing packaging, with this set up the wastegate would exit above\below the tailpipe, having little impact on other packaging and the horseshoe wing pillar wrapping around them. With a mickey mouse set up wrapping a Y-lon horseshoe mounting around the three pipes will be bulky. STR had a good solution last year and passed the pylon straight through the exhaust tailpipe, this would work especially well in keeping the bodywork aerodynamically slim at the back of the car.

Picture from Mercedes AMG Petronas Youtube Channel

Mercedes W07 Fire-Up video, shows a inverted Mickey Mouse set up (two wastegate pipes below the main tailpipe.  This may be seen in testing, but its not a problem for the team to alter the tail pipe design through testing for another solution.

TRENDS

‘Squarch’ Front Wing

AS_Merc_FW

Mercedes took the lead with their square arched (hence my term Squ-arch) front wing, the arched section forming part of the outswept design. Last season nearly every team with any budget followed the same concept of outswept shape and arched outboard wing profile. The next step is merely more exaggerated shapes and complexity in this area.

Nose shape

This will be the first season of stability in the nose regulations for several years. There’s a consensus that a short nose is best, to free up airflow to the rear of the car and also to reduce the interaction with the top part of the front wing centre section. From there though opinion differs from the wide wedge shaped of Williams and the less copied Mercedes narrow shape. Both solutions are likely to be popular and both are likely to see the teams growing in confidence in the amount (or lack of) of crash structure required to meet the rules.

Nose_Slimmed
Once you have a short nose, you can only make it thinner to improve its aero, by making the nose narrower or shallower in cross section from the mandatory frontal cross sections. Both reductions in section make it harder to pass the crash test, including the twist test to the nose\front wing assembly. However, recalling the very narrow nose of the Caterham in 2014 (ignoring the wedge shaped vanity panel) it could be possible to go very narrow, having a tube-like structure trailing from the front wing only flaring out before the front bulkhead. With such a narrow nose comes the issue of front wing mounting. The narrow spacing of the front wing mounts on the Caterham made it impossible to use the mounting pylons as turning vanes, while the regs make it hard to extend the pylons sideways from the nose to mount the front wing, due to the single cross section rule.
One team employing just such a conical inner nose structure last year was Toro Rosso, whose nose when viewed from the inside tapered down into the protruding nose tip, the outer wedge shape of the nose and the wing mounting pylons were bonded on, albeit still part of the nose’s structure. This makes it easier for them to slim the nose in this way.

Nose_Vented
Force India’s vented nose is also a curious development, for FIF1 in 2015 it was a pragmatic one, not investing huge amounts into a very short hard-to-crash-test nose, meant that venting a longer nose gave the aero gains of a shorter nose, without the crash test issues. Its likely FIF1’s nose’s inner structure was similar to STR, with conical inner structure flanked by bonded on outer sections.
Even with a short nose, if the structure allows, a vented set up could be used to further increase air flow under the car. The resulting flow structure may be more complex in order route the air through the nose, so it’s a compromise, but if it can be made to work it’s a possible route. So with either the conical inner structure construction for the nose (ala FIF1 STR), Or Williams with the bulk of its material in the side faces of the nose, a short vented nose could be realised.

S-Duct

Nose_SDuct

One way of cleaning up the airflow from a shallower nose is the S-Duct, described to me as “a small gain, but well worth it” last year when McLaren switched over to an S-Duct. In side elevation its clear to see how a shallower nose’s transition into the front bulkhead is eased by the aero effect of the inlet and outlet. Otherwise a noticeable step in the transition twixt the nose and monocoque is a more difficult aero problem.

Mercedes may have testing elemens of an S-Duct late last year, with the dummy nose panel run on the cars in the last few races.

Chassis height

Picture Via @Lotus F1 – Now @RenaultSportF1

Most teams have maxed out the available height for the front portion of the monocoque. A few teams still leave some sections of the area just behind the front bulkhead lower than permitted, so we can expect to see a very car with a pronounced hooked front footwell area.

Blown Wheel Nut

These initially looked to have gains some favour early last year. However, improvement to the front wing’s outwash effect and the need to reduce drag for higher EOS speeds, meant that the system was often switched to conventional closed axles for some teams. This year I’m expecting it to be an option for more teams. With teams running it as a set up option at certain races and running pointed-closed axles at others.

Picture via @ToroRossoSpy

Toro Rosso have been practising pitstops with oversized open front axles, suggesting they be going down this route.

Front Turning Vane designs

An area of near standardization last year. Most teams switched from simple arrays of individual vanes, to a 3-4 vane set up joined by a common footplate. This is likely to be standard across the grid, with Ferrari copying the Mercedes Batwing, it will be interesting if other teams place similar inverted wing vortex generators behind the usual FTVs

Suspension design

The Mercedes conjoined front lower wishbone idea from 2014, gained favour in 2015 with Ferrari and Force India following a similar path. This isn’t a must have solution, depending on your wing and turning vane set up, but is more likely to adopted by others in 2015. There are weight issues to keep the wishbone and the monocoque stiff enough with the reduced span and area for the inner mountings.
Although Mercedes also caught a lot of attention with the change in the front inboard suspension layout late year. The car always sported hydraulic set up (they called it a gas spring). It merely sat below the coil heave spring and was largely unnoticed, despite the hydraulic unions being evident on the front of the bulkhead all year. Most teams employ hydraulic set up and increasingly is it replacing the front mounted mechanical spring, with remote mounted hydraulic elements achieving the same role as the front heave spring.

Sidepod layout

Sidepod shape and volume is largely dictated by the power unit’s cooling demands. With Ferrari and Mercedes being the lighter of the PU’s on heat rejection and Renault being the heaviest, especially on charge air cooling. However, the winter 2014-2015 saw both Renault teams admirably reduce their sidepod volume, through careful aero design. While Ferrari’s louvered radiator faces allow a particularly compact sidepod design erring towards the old Sauber narrow sidepod, a trait I expect to be more dramatic this year and copied by many teams.
At the rear the cooling outlet area is largely standardized to wide coke bottle exits, the canon style tail exit losing favour for bodywork wrapped tightly to the exhaust and rear wing pillar.

Radiator position

Along with the external aero aspect of the sidepods, the choice between sidepod or overhead mounting of the coolers is split across the grid. Most teams have the IC engine water\oil coolers in the sidepods and those with air-to-air intercooler place then in the opposing sidepod. The overhead inlet mounting is largely for an ERS cooler along with the gearbox and hydraulic oil coolers. Both Manor and STR fitted the oil cooler between the engine and roll hoop, an interesting solution, greatly reducing sidepod volume, but costing some wheelbase as the fuel tank has to be lower and thus longer to package a gap to place the cooler and its ducting. With STR having a longer Ferrari powertrain this year, it’s possible they may have to discard this option, to preserve a reasonable wheelbase if development time allowed them that luxury, such was the short notice of the Renault to Ferrari engine switch.
Ferrari are also likely to move their water to air charge cooler, from within the engine’s V to the sidepod or possible Mercedes in front of the engine in a recess in the fuel tank area. The Mercedes solution is a neat package for their front mounted turbo compressor but does compromise wheel base due the fuel tank length increasing to offset the intrusion of the intercooler (plus oil tank, airbox and compressor). It was largely unnoticed that Lotus ran a floor mounted W2A charge air cooler in 2014, so James Allison may find this is a better route for the rear mounted Ferrari turbo compressor.

Gearbox

Gearbox_comparison

An increasing trend since the 2014 regs were brought in is to raise the gearbox case clear of the floor beneath, aided by the higher mandatory crankshaft position up to 90mm from 58mm, this means the casing can shrink inwards around the rear inboard suspension and the gear cluster mounted towards the centre of the case. Doing this allows the stepped floor to merge into the lower central step to direct more airflow across the full width of the diffuser. Shrinking in the sidepods and the undercut under the gearbox will be more noticeable this year, looking like the rear of the car is cantilevered over the floor. Ferrari are rumored to have repositioned the MGU-K s on its PU specifically to allow this narrowing.

Diffuser
After years of overt difference in diffuser shape, the grid has converged in this area too. Every team have added one, two or three layers of flap over the diffuser trailing edge to lower pressure behind the diffuser. With that avenue exploited its largely the outswept shape of the diffuser in plan view that remains a development route. Often the diffuser will partly exit sideways through the 1000mm maximum width. Working the centre section along with the exposed floor under the gearbox means that the taller allowance for flaps\gurneys cascading up through the monkey seat and top rear wing.

Rake
With the diffusers height limited, the other route to exploiting underbody downforce is the rake angle of the car. Teams are increasing rear ride height and lower at the front to make the entire underfloor raked against the track. Rear ride heights are well over 100mm possibly nearer 150mm, this near doubles the diffuser’s effective height, while the front wing being lower works more in ground effect. Issues surrounding this are keeping the diffuser from stalling at the increased ride height, preventing in-wash from around the floor and tyre squirt off the rear tyres upsetting diffuser performance. With FRIC banned teams are still using complex hydraulic set ups, now unlinked, but still able to manage the ride height far better than simple springs, dampers and rubbers.
At the front aggressive rake causes issues with the lower leading edge of the front wing endplates, which can often be chamfered to clear the track when pitching under braking. Of course the key limit is grounding the splitter, a change to Titanium skid blocks prevented teams running harder metals and grinding the splitter in to the track to allow it to bend and allow a lower front ride height without undue wear, a legality issue. Many teams run a complex carbon fibre splitter mount, looking like a fat tube with an axe head, the splitter supports meet the FIA test and still allow enough flexibility to run the car angled steeply against the track. Teams with simpler metal slitter supports will no doubt move towards more exotic ones as they start to get more extreme with rake.

Rear Tyre squirt slots
Airflow coming off the rear tyres enters the diffuser and upsets it performance, an effect known as tyre squirt. The slots in the rear part of the floor are increasingly more aggressive to direct a jet of airflow to offset the tyre squirt. Ferrari and McLaren went to over ten slots in the floor in order to work this area harder, as testing continued we can expect other teams to fit equally manifold and complex slots in the edge of the floor. Look for large removable sections molded into the floor when they cars are launched for a clue to who is looking at this area.