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Marina Bay
Circuit: three corners in detail
Turn 3
The Marina Bay circuit has 23 corners, of which 10 are taken in second or
first, 7 in third and only 1 in fourth gear. Corner 3 is a good example of a
‘typical’ Singapore corner. The driver brakes down from around 290kph at the
end of the pit straight, shifting down the gears before a quick blip of the
throttle for turn 2. He then brakes even further, shifting down to second
gear for turn 3. The speed at this point will be under 100kph and the engine
will be working at around 13,000rpm, the lower end of the rev range.
Engineers will work on the overrun settings to give increased rear stability
under braking. They will also look at using shorter gear ratios to maximise
acceleration for the short bursts of power between the corners.
Turns 5 - 7
Singapore has just two short straights: the pit straight and then the curved
straight between turns five and seven, which shoots down Raffles Boulevard
with its luxury hotels and boutiques. This short straight – only 700m – will
see the driver engage seventh gear and touch the 300kph mark, giving the
engine a chance to breathe. With the ambient temperatures generally over
30°C, even at night, it’s a welcome opportunity, particularly as after turn
7 the track goes into a series of low speed, low rev right angled corners
for the remainder of the lap.
Turn 15 – 17
This sequence starts in Raffles Avenue, one of the city’s busiest urban
thoroughfares. As a result the surface is quite bumpy and the car may become
unstable, particularly under braking for turn 16, a sharp right-hander.
Similar to Monaco, the drivers will try to avoid the biggest bumps, which
cause the cars to lift momentarily. With no load running through the engine,
the engine suddenly accelerates and hits the rev limiter, causing a loss of
time and potential damage to the engine. Engineers will therefore pay
particular attention to the shift light pattern and even encourage the
driver to shift early to avoid hitting the rev limit too often.
Rémi Taffin, Renault Sport F1 head of track operations:
Singapore is a very different challenge to the high power tracks of Spa and
Monza. Most obviously, it is a street track, winding its way round some of
the city’s most famous landmarks in a series of low speed, low rev turns. In
sharp contrast to Belgium and Italy, power sensitivity is amongst the lowest
of the season as less than 45% of the lap is spent at full throttle and the
average speed is around 170kph. The new T10, now a straight left hander
instead of the sling corner, slightly increases the percentage of wide open
throttle time and fuel consumption, but the nature of the Singapore track
remains unchanged. 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.
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 year
so we try and be as careful as we can with the engine settings to avoid a
weight penalty. 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. Getting the correct fuel load for the start is
one of the major challenges of the weekend as engineers will also have to
consider the likelihood of weather changes and safety cars.
Unusually, given the local climate, we have not had a wet race in Singapore,
but even without rain humidity can be well over 80%. This also plays a role
in the configuration of the engine as the higher the water content in the
air, the less oxygen there is available to burn so power output drops
slightly. This is offset by the race taking place at close to sea level and
the circuit’s relatively low power requirements, but it is nevertheless an
important consideration when we look at engine maps and operating
parameters.
Temperatures are also something to watch carefully – particularly as the
race is the longest in duration of the year. 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. For these reasons we tend to use an engine at the end of its life. |