The Formula 1 World Championship lands in Singapore this week for the 14th race of the 2012 season.In contrast to the previous two events on the calendar, the Singapore Grand Prix places an emphasis on low speed driveability and engine response. The 5.073km circuit has a huge 23 turns — more than any other track on the calendar, bar Valencia — as cars pass in and out of the office blocks, luxury hotels and state buildings. The average speed is therefore correspondingly low, with cars circulating at just 170kph over the lap. Top speed is just over 305kph between turns five and seven with DRS and KERS activated and under 50% of the track is spent at full throttle; two thirds of the figure from Monza.
Singapore Grand Prix engine facts and figures:
Twenty two of the 23 corners are taken in first to third gear, so for the vast majority of the lap the engine is working at between 8,000rpm and 13,000rpm on the corner exits. The engine maps need to deliver good driveability through the low speed and low rev range as accurate torque response and stability are key. Getting the correct gear ratios in the lower level can also improve grip, and ultimately lap time, in this respect.
The engine is only given a chance to breathe on two short straights, the pit straight and then the curved straight between turns five and seven. In fact seventh gear will only be engaged three times per lap; only Monaco has a lower usage.
The stop-start nature of the track and the short bursts of acceleration between the turns make Singapore one of the least fuel efficient of the season and consumption per kilometre is extremely high compared to the last event at Monza. Getting the fuel load for the start is one of the major challenges of the race as engineers will also have to consider the likelihood of weather changes and safety cars.
While temperatures during the night are typically lower than during the day (between 5 and 6°C cooler), the enclosed nature of the track between the buildings keeps ambient temperature high. Cooling systems are therefore carefully monitored, particularly since the cars are going relatively slowly and often circulating closely to each other, raising the operating temperatures further.
Singapore’s equatorial location gives it a very tropical climate and humidity is often over 90%. The high water content in the air displaces the air being ingested into the engine via the air filter, reducing the amount of oxygen that can be combusted with the fuel. This makes the engine output less powerful so different engine modes will be used to negate the power loss.
Racing at Night
The challenge of racing at night and negotiating the tricky 23-turn street track, poses unique difficulties. With the vast majority of turns taken at low speed, a neutral set-up is critical to the perfect lap and the perfect race. As Renault Sport F1 engine engineer for Red Bull Racing David Mart explains, the role of the engine engineer is a crucial piece of a larger puzzle that sees everyone aiming to maximise their own areas to give the driver exactly the set-up he wants from his car.
The work between engine supplier and team begins even before arriving at the track. In the days leading up to the race, simulations and dyno tests carried out at Viry Châtillon produce huge volumes of data that is collated and sent to the individual teams to help them take an initial decision on set-up.
“The initial information that we collate at the factory goes into a brief report, which outlines operation for the event. It is sent the week before the race and includes data from the simulations we run at the factory,” David divulges. “It takes input from laps we did the previous year and from data for the current car at the other circuits this year. This allows us to predict fuel consumption and the effect of engine performance for the track layout.
“You will also predict engine temperatures from data you’ve collected and thus what cooling levels you think the car needs to start on. There are different blanking options on different panels of the car and that allows you various options going into the sessions to cool the engine and gearbox. Also the gear ratios will be predicted. All these baseline settings are then tested during the practice sessions at the track.”
From these practice sessions onward, there are numerous briefing and de-briefing sessions over the weekend, during which any alterations are discussed and any planned changes proposed.
“The actual briefings are broken up between everyone involved. It will start with the driver and then their engineers and performance engineers will relate their findings, and the relevant engineers will discuss aerodynamics and then we’ll look at the engine, gearbox and KERS. We’ll decide if the cooling levels are adequate and if we need to make a change, and obviously we’ll get a better idea on fuel consumption and be able to amend our predictions.”
With the ban on in-season testing, the quality of simulation work has reached such a high level that teams arrive at tracks with a pretty clear idea of what needs to be done and what set-ups need to be tried. As David explains, there are rarely many calls for any major amendments.
“It is very rare that you will deviate from what has been established in simulations as being the optimum for the track. It is usually just fine tuning.
This is where the relationship between the chassis engineers and engine engineers needs to be seamless as each relies on the other to feed information to get the maximum from their own specific area. As David explains, this is key to getting the most from the weekend.
“Some of the jobs that the chassis engineers do and that we as engine engineers do, interlink. We both react to driver feedback as to how the weekend and the direction of set-up has developed. On the engine side we’ll work on pedal maps, improving response in the provision of power.
“We also react to changes to the set-up such as a shift in aerodynamics. We have to be constantly aware of set-up changes, because that will affect how the power needs to be delivered. For instance, if a big change is made in terms of downforce levels, and the guys are looking for longer at full throttle or higher top speeds, then we might need to look at ratios, how the engine behaves in cruise at the end of the straight and then throttle maps to ensure that we are taking advantage of the increased window we’ve been afforded by a set-up change from an engine perspective. It is an iterative process until we arrive at the perfect set-up for the driver that allows him to put together his perfect lap.”
Renault Sport F1’s Rémi Taffin
“After the high speed races at Spa and Monza we go to Singapore and one of the slowest tracks of the year. Power sensitivity is amongst the lowest of the season as only 46% of the lap is spent at full throttle. This means top speed is not so important here; instead we focus on a smooth power curve in the lower rev ranges and good response out of the high number of corners.
Fuel consumption is one of the highest of the year due to the start-stop nature of the track so the starting fuel load is one of the heaviest we see in a season. To avoid finishing with too much fuel on board — and therefore a time penalty per lap — or too little fuel, drivers constantly play with the engine modes, adjusting to have more or less rich fuel mixtures. However, due to the low power sensitivity, we can use leaner engine modes to try to reduce the fuel at the start of the race, which effectively acts as ballast.Tyre wear is always quite high due to the abrasive tarmac of the everyday roads, manhole covers and lack of rubber at the start of the weekend. We can reduce some tyre wear with engine maps that increase rear stability and grip, enabling our partners to be more creative with the pit stop strategy.
We are pretty confident that we can deliver round the streets of Singapore; the RS27 has so far performed well on street tracks this year and circuits with low average speeds so we are looking forward to helping our partners achieve some good results”.
