Take a look at the track layout in the chart inset, it’s like I said. This ethos is a clear focus within the rules which reward high performance, minimal drag and low fuel/energy consumption – all of which can be achieved through the use of aerodynamics. The difference between downforce & drag 30 August 2018 by Leopold Nick Chester - Chassis Technical Director at Renault explains downforce and drag on F1 cars. Downforce vs. Downforce is most useful in fast corners and while braking. Drag is the tendency for air to slow the car down. In other words if you shaped the cooling fins etc corectly in the radiators could you generate downforce? Downforce is necessary for maintaining speed through the corners. Also, as was pointed out earlier, drag reduction for race car airfoils is less important than the downforce. I took my ZR1 RM, set the gearing to maximum, set the downforce to maximum (35 and 60, front and rear, respectively), and went flat out on SS7. Downforce vs. Cd .48, Cl -.53. spoilers are accurate for all the cars I can think of. To really simplify things I think what the article you're read is trying to say is that "downforce" (even though ground effects don't really use downforce) in today's F1 cars is made from the top of cars by using wings, vents, and winglets. Most provided wing data is free stream tested, meaning, they aren’t the exact numbers you’ll see on your car. View image | gettyimages.com. Or conversely, how much downforce for a given level of drag. ( Log Out /  Aerodynamic downforce and drag increase with air speed squared. Miatas are all about cornering anyway, and we’re used to getting passed on the straights! Another elevating aspect of Downforce is the special power cards. I have two Miatas, and even my faster one is slow. Nick Chester - Le directeur technique des châssis chez Renault explique les forces d'appui et les freins des voitures F1. In conceiving their W10 this year, Mercedes opted for a more even spread of performance on all of the circuits of the season, feeling that the previous two cars were super-strong through high-speed corners but less adept through slower ones. In other circumstances, it can do quite a bit of damage, due to its extremely high temperature, severely damage the car mechanically (such as melting the wings). 5(b)). Downforce vs Drag. There are six special power cards in each game, one for each car, and they break the rules of the game in interesting ways. Typically, that means the car is slower on the straight than one with less magnetic downforce. As we will see later on, more downforce means that the car will have the ability to negotiate corners faster, with its effects getting more and more relevant as car’s speed (relative to the air) grows (which means, corners radii gets bigger). The wings of birds were the original inspiration for the design of aerofoils however it was not until 1799 that engineer George Cayley carried out the first methodical study of the performance of aerofoils. Aerodynamic downforce on the other hand, increases vertical load on tyres without much penalties, except for the commonly added drag that comes with it. But they produce big forces at high speeds, which are mostly on the straights where you don’t want downforce or drag. Drag reduction is more critical on the speedway than on other circuits. Drag reduction matters most when accelerating on a straight, but pretty much everywhere else downforce is preferable to drag reduction. When Matt Kenseth took the win on Sunday, it ended another 400-mile test session that NASCAR implemented a different rules package than what was used to start the season. Another consideration is rules. You can read more about that in Downforce vs Drag. This relationship has a huge consequence. ... Basically, any force that acts in the opposite direction the car is going is called drag. Downforce uses nature to help the car by directing airflow to push the car into the track, enabling far better grip and stability. However, compared to a high-mounted rear wing, a diffuser is a more efficient means of producing downforce, where efficiency is measured as the lift[downforce]-to-drag ratio. diandra says: 2015-07-26 at 12:05 pm. olpro wrote: Since it seems to come down to drag vs downforce,why isn't it more effective to properly size a wing above the car's rear? If the spoiler were horizontal, you’d get all downforce. Downforce is a downwards lift force created by the aerodynamic characteristics of a vehicle. Perhaps most importantly in a racing application (particularly road racing), aerodynamics can also be applied to produce downward lift, or “downforce”. But, with corner speeds of approximately 15-20mph, it could be argued that adding downforce in the corners is not as effective as first thought, making these extravagant wings essentially ‘dead weight’. Calculate downforce for a wing; Calculate drag for a wing; Calculate ratio of downforce to drag; Enter your wing angle, wing area, and vehicle speed. Once you know how much rear downforce you want to make, look at the wing’s downforce vs. speed data. Drag Like all great road racing cars we had to get started with the rear wing...bigger is better...or is it? In the future most of the downforce will be created underneath the car much like today's Indycar. In fact, the downforce and drag vs. height curves resume an almost linear behaviour after the initial ‘plateau’ at the beginning of the region b (Fig. That part creates drag while decreasing downforce. Aren’t those two things basically the same? Still, it makes me wonder if we should chase all the downforce we can and not worry about drag reduction at all. Drag is an aerodynamic force that opposes forward motion, thereby limiting top speed and acceleration. Putting the same wing on the back of a slippery Toyota Prius will see different downforce and drag numbers compared to being mounted on a convertible Mazda Miata. I just read that in 2022 the cars will have “less downforce and rely more on ground effects.” I am confused. Polar curve showing glide angle for the best glide speed (best L/D). It also creates ‘drag’ on straights – the motor needs to work hard to overcome the magnetic ‘pull’. Dustin Parks August 18, 2015 NASCAR, Sprint Cup Leave a comment 1,898 Views. Items under the car are out of site and out of mind. Downforce vs. As those of you familiar with the Noble M12 GTO will remember, the Noble has a huge rear wing which Noble persisted aids with handling characteristics. Using the expertise of industry professionals, we look in detail at racecar design and innovation, whilst also keeping you up to date with news and developments from all the major race series across the globe. In other words if you shaped the cooling fins etc corectly in the radiators could you generate downforce? It’s all about the ratio of downforce vs. the amount of drag. It is pretty straightforward to understand drag’s effect: drag is a force that acts against car’s forward movement and that try to decelerate the vehicle. If the spoiler were perfectly upright (vertical), all the force would be drag. What is the downforce pressure on MKII GT40 and what is the downforce difference between MKI and MKII? A Formula Student car is a different beast to any other category of Motorsport. Drag vs Speed. Magnetic downforce gives the car more speed and stability through corners. For the most part, increases in downforce produce increased drag--sort of like having a parachute attached. Generally, generating downforce in turn makes drag (induced drag) so if you crank up your wing's angle-of-attack to make more downforce and be quicker through a corner, the extra drag will cost you top speed in the straights. These are a nice addition to the game. Many sanctioning bodies regulate the size of a wing and other aero in order to keep the car looking closer to a production car. Fundamentally, Formula Student is an engineering competition, and any engineer will always seek to improve the efficiency of his or her design. Drag Like all great road racing cars we had to get started with the rear wing...bigger is better...or is it? Before we deal about how downforce and drag are generated, let’s try to understand in a bit more detail why and how they affect car performance. Page 1 of 4 - Drag Vs. Downforce - posted in The Technical Forum Archive: In Autocar magazines 4th May issue Chris Harris joined Noble Automotive in testing their new Noble M400 to find out its top speed. Tech Explained: Formula Student Aerodynamics, ASI Connect digital 2021 + Autosport International 2022, News: Ferrari to enter Hypercar LMH in 2023, Mecachrome and Alpine Racing Formula 1 continue technical partnership, Developing a Disadvantage: MV Agusta Moto2, ARA and DirtFish partner to support the growth of US rallying. Terms & Conditions | ‘During the lower cornering speeds, the downforce values tend to be less than half of this. Privacy Policy | But that actually sets the worst lap time, some 6 seconds off the pace. Air flows around, under and through your race car, and you can take advantage of it with cheap and simple modifications that have a big performance payoff. Downforce vs Drag. © 2021 Chelsea Magazine Company | Therefore, due to these relatively low speeds and the high power of Formula Student cars, drag is not such a big factor in our design, so we are always pushing for downforce.’. Find the lift coefficient (downforce coefficient) , drag coefficient, maximum lift amount (downforce amount), minimum drag amount, and lift to drag ratio (downforce to drag ratio). The Formula Student team from the University of Sussex investigated this idea and found that downforce was definitely noticeable above 30mph. which is particularly important at the upcoming Italian GP at Monza . Formula E's inaugural driver's champion, Nelson Piquet Jr, provides a quick no-nonsense explanation of the principles of aerodynamics. Miata aerodynamics, endurance racing, and DIY. 1. The freedom of the regulations allows these young engineers to experiment with all types of wings, flaps and aerofoils and with the narrow and twisty circuits demanding downforce; Formula Student has become famous for its enormous wings. Inlet velocity is set at 20 m/s (72 km/h) which is quite reasonableconsidering th… I may have underestimated both the amount of drag and downforce a spoiler can produce. There's no doubt that a diffuser will produce drag. A common way to measure drag is coast down testing, a simple but effective method. ( Log Out /  IndyCar's silly downforce levels in road and street course trim--reaching upwards of 5500 pounds at many tracks--is produced with the same kind of huge topside aero found in F1. Low Downforce vs. High Drag: There is No Comparison. Drag vs Downforce A few years ago TU Munich had a rear wing big enough to sit four people! ( Log Out /  In contrast to ordinary vehicle aerodynamics, race car aerodynamics focus mainly on downforce magnitude and distribution, whereas drag force is of secondary importance. Gemma has a BEng in Mech Eng from Bath University and an MSc in Advanced Motorsport Eng from Cranfield University. Downforce comes with six special power cards that break the rules of the game in some way. This is a calculation, albeit a very sophisticated one, and it’s based on a race car with a lot of power that can overcome drag. Or you might think to optimize for the highest L/D ratio, and with that you’d at least be within the same second as the fastest cars. Privacy Settings. The final mesh has close to 8 million cells with a porous zone for the radiator and a MRF (multiple reference frame) zone for the wheels. Page 1 of 4 - Drag Vs. Downforce - posted in The Technical Forum Archive: In Autocar magazines 4th May issue Chris Harris joined Noble Automotive in testing their new Noble M400 to find out its top speed. In contrast to ordinary vehicle aerodynamics, race car aerodynamics focus mainly on downforce magnitude and distribution, whereas drag force is of secondary importance. Parasite plus Induced) Coefficients of Drag and Lift vs Angle of Attack. Drag is the resisting force the vehicle experiences from air pushing against it and the additional weight that downforce creates. A Formula Student car is a different beast to any other category of Motorsport. Unwanted drag which accompanies downforce will slow the car. Here are our CFD links and discussions about aerodynamics, suspension, driver safety and tyres. The balancing act is this: If there is a shortage of grip in the corners (too much sliding or a loss of control) then downforce will increase grip and increase speed POTENTIAL in mid corner. Ground Effects 09-05-2020, 08:58 AM. Downforce and Drag increases at the square of speed, divided by a constant. Change ). Lift and drag vary according to the angle an airfoil makes with its direction of travel through a fluid. D. David Morton. The downforce helps the car negotiate the turns at a faster speed, and the drag slows the car and reduces the top speed down the straights. A F1 car can produce enough downforce to drive upside down (three times the car's weight in certain configurations). Every issue provides unrivalled technical analysis of everything from World Championship series including Formula 1, to grass roots racing. Consistently, throughout the lap, hit a terminal speed of 372 km/h. The wings of birds were the original inspiration for the design of aerofoils however it was not until 1799 that engineer George Cayley carried out the first methodical study of the performance of aerofoils. The difference between downforce & drag 30 August 2018 by Leopold Nick Chester - Chassis Technical Director at Renault explains downforce and drag on F1 cars. But somewhere in the neighborhood of maximum downforce, that’s where the fastest lap time was. At a first principles, the balance is between amount of downforce vs drag. ­Balancing downforce and drag within the confines of the NASCAR-sanctioned car body is a trick the teams simply have to deal with in the best way they can. I got into a conversation about drift cars and wings (I know, I know.. The CFD simulation is RANS based with the well-known k-omega SST turbulence model. What a … Pirelli is expecting F1 teams to "quickly recover" the downforce that will be lost by the tweaked aerodynamic regulations for 2021. If we look a front wing for example, which produces say 10lbs (4.53kg) of down force at 40mph (64.3km/h).If the same wing increased speed to 80mph (128.74km/h), the amount of down force generated would be 40lbs (18.14kg). That comes from a two-headed, but singular, conundrum that every serious sports car faces – balancing downforce vs drag perfectly. It was thought by many that a team cannot have both. Rad drag vs downforce - posted in The Technical Forum Archive: Hi - This was inspired by an earlier thread and Xmas spirits so please ignore it if its a totally stupid idea ;) There is a lot of talk about how much drag is generated by radiators. I did a motorcycle track day at Portland International Raceway, and I’ll describe it like this: it has a really long and boring front straight, a couple corners, another long and slightly less boring back straight, and a couple corners. Reply. The last thing you want to do to an underpowered car is add more weight and drag, right? Do we put a massive wing on this car to make it corner at low speeds...but generate so much drag that we sacrifice top speed? With some designs achieving power to weight ratios of 1hp/kg, these cars extract phenomenal performance out of their Motorbike engines, or electric motors. Aerodynamic Lift and Drag and the Theory of Flight . Lift may also act as downforce in some aerobatic manoeuvres, or on the wing on a racing car. For the most part, increases in downforce produce increased drag--sort of like having a parachute attached. So let’s examine downforce vs drag on a very fast racetrack that is dominated by long straights and top speed. His publication "On Aerial Navigation" in 1810, marked the beginning of the science of Aerodynamics. Downforce is created by the air moving over the top of the car and pushing it down toward the track surface. Do we put a massive wing on this car to make it corner at low speeds...but generate so much drag that we sacrifice top speed? And so I’ve verified, somewhat, that it in GT5, there is a downforce vs. drag change. Having an over abundance of rear downforce will make the car understeer at high speed (safer), which means you can tune the car for oversteer at low speed (funner). Low Downforce vs. High Drag: There is No Comparison. Change ), You are commenting using your Facebook account. Furthermore, designing clever aerodynamic devices can also reduce drag which in turn improves fuel consumption and this can equate to many marks in some of the dynamic events. Please stick to F1 on this forum. She has worked trackside in BTCC, GT and F1 as a Tyre Engineer for Pirelli and then Manor F1. The efficient design of a chassis is based on a downforce/drag compromise. ‘Compared to Formula 1 we are almost unlimited in terms of Aerodynamic regulations because we have no standardised parts, no restrictions on the number of aerofoils and large design spaces,’ explains Niklas Pfeiffer, Head of Aerodynamics and CFD at the Cologne Formula Student Team. Stability and handling of a race car strongly depend on tire performance, which is directly linked to the balance between front and rear downforce. Proper shaping of the vehicle can help to reduce this drag. ce qui est particulièrement important lors du prochain GP d'Italie It contrasts with the drag force, which is the component of the force parallel to the flow direction. The relationship between drag and downforce is especially important. We all know that additional downforce improves the car’s performance and thus reduces lap times. Advertisement. Aerodynamic improvements in wings are directed at generating downforce on the race car with a minimum of drag. Four of the most effective modifications for […] So let’s examine downforce vs drag on a very fast racetrack that is dominated by long straights and top speed. ‘The circuits we race at don’t have long straights, so the maximum speeds we reach are around 120kph, which is roughly what a Formula 1 car achieves at the apex of a second or third gear corner. Change ), You are commenting using your Google account. It can produce more downforce than the weight of the racecar and this force is the square of the object velocity (double the speed and you get quadruple downforce and drag levels). Using Drag and Downforce to Tailor Stock Cars to Different Tracks. But isnt aero downforce just controled drag? As those of you familiar with the Noble M12 GTO will remember, the Noble has a huge rear wing which Noble persisted aids with handling characteristics. Comparing the two versions, the spoiler has .03 more drag, and .09 less downforce. You should start by learning the difference between spoiler and wing. Most teams spend a lot of time and money deciding how much downforce to use verses how much time is lost to drag. Racecar Engineering is the world’s leading publication for motorsport technology and engineering. Oil flow observation also indicates the limited extent of the separation (Fig. Change ), You are commenting using your Twitter account. It also creates ‘drag’ on straights – the motor needs to work hard to overcome the magnetic ‘pull’. Lift and Drag Coefficients. However, any amount of downforce is worth chasing because it increases the handling, tyre grip and confidence in the corners, which is particularly beneficial for amateur drivers.’. Downforce uses nature to help the car by directing airflow to push the car into the track, enabling far better grip and stability. Stability and handling of a race car strongly depend on tire performance, which is directly linked to the balance between front and rear downforce. Bruno Massel has more in #TechTalkTuesday presented by Evans Waterless Engine Coolants USA. 2). Or so you’d think. One way teams make the most of these on-track forces is by bringing the third D into the mix -- drafting. It has been appeared that, for higher angle of attack the drag coefficients are higher. L/DMAX occurs at minimum Total Drag (e.g. Downforce and Drag increases at the square of speed, divided by a constant. DIY Modifications to a Cheap eBay Wing, Part Deux, Calculating Drag and Lift From Body Shape, Lemons Aero Study: Star Wars Ecotec Miata, NACA Wing Shapes and Airfoil Tools – Occam's Racer. Why a Different Package for Indy vs. Kentucky? Rad drag vs downforce - posted in The Technical Forum Archive: Hi - This was inspired by an earlier thread and Xmas spirits so please ignore it if its a totally stupid idea ;) There is a lot of talk about how much drag is generated by radiators. However, at these lower speeds, does having extra downforce really matter? The major downforce is found in the shape of the body and underbody. It was thought by many that a team cannot have both. The magnitude of the coefficient of lift depends on the shape of the body and its angle of attack [8]. What is revealing is the sudden increase in … Cookie Policy | Typically, that means the car is slower on the straight than one with less magnetic downforce. Drag is the tendency for air to slow the car down. Diandra Leslie-Pelecky. Divo and Deep Blue dont have a spoiler. (The driver must utilize some of all of this potential speed.) Coefficient of drag is a unit less number, which indicates a body's ability to generate fluid resistance [7]. High spoilers, wicker bills, bigger roll pan, all of … ‘After many hours of software and experimental testing our 2017 aerodynamic package produced 246N of downforce and 126N of drag force at 30mph,’ highlights Oladapo Oyelami, Head of Vehicle Integration at the Mobil 1 Sussex Racing Formula Student Team. As for why the cars are getting loose while in traffic, that has yet to be seen. ( Log Out /  Adding an airdam, splitter, side skirts, wing, and all the other aero bits add weight, and some of them increase drag as well. With some designs achieving power to weight ratios of 1hp/kg, these cars extract phenomenal performance out of their Motorbike engines, or electric motors. Most hypercars opt for active aero that give more control over drag vs downforce. Question about spoilers and downforce/drag/exc. Stall speed corresponds to the Angle of Attack at the Maximum Coefficient of Lift. In evaluating an airfoil it is common to perform an alpha sweep that records the lift and drag … The downforce helps the car negotiate the turns at a faster speed, and the drag slows the car and reduces the top speed down the straights. Lifetime Supporter. This angle is known as angle of attack, angle of incidence, or alpha. It is the flattest possible glide angle through calm air, which will maximize the distance flown. Now, in the 70s there were the “fan cars,” which I guess were the epitome of ground effects, but I don’t think F1 is going in that direction! But isnt aero downforce just controled drag? Maximum Downforce. I should probably re-run the data using a Cd of around .50 and a Cl of -.40. Up next, we'll take a closer look at drafting. Dustin Parks August 18, 2015 NASCAR, Sprint Cup Leave a comment 1,898 Views. Of course, highly skilled drivers may feel this change but for smaller teams with lower budgets, pursuing complex carbon fibre wings can be expensive and difficult to manufacture. But like most things aerodynamic, what seems obvious could be completely wrong. At this track, you might think that you should set your aero for the least possible drag, thereby attaining the highest top speed. She has been writing for Racecar since 2010, using her engineering experience to unravel modern motorsport technology. The balancing act is this: If there is a shortage of grip in the corners (too much sliding or a loss of control) then downforce will increase grip and increase speed POTENTIAL in mid corner. Later version with a wing. Mar 12, 2009 #2 Who knows? Downforce increases drag. Even still, there are times when drag reduction is more important, such as in an endurance racing strategy where you want to do one less pit stop. IndyCar's silly downforce levels in road and street course trim--reaching upwards of 5500 pounds at many tracks--is produced with the same kind of huge topside aero found in F1. More downforce, at the expense of more drag, is almost always faster. Aero devices don’t do much in slow corners, just when you need them the most. Maybe. I’ve talked to one engineer who claims the downforce is a little lower (Kyle Busch also said this) and one who says its a little higher. If ever there was a track where you’d want to reduce downforce and optimize for less drag, this is probably it. It also seems logical that at a high-speed track you’d want to skew your aero package towards top speed and reduced drag, especially in an underpowered car. Increasing downforce will (normally) increase drag, without adding more HP to overcome the drag the decision needs to be made where best to use the available HP (straight line speed or downforce). This exhaust gas can, in certain circumstances, be used to reduce drag or increase downforce. The full results are in SAE Paper 920349, but this is what I make of it. In Kentucky, NASCAR went with a shorter spoiler to reduce the downforce. In Race Car Aerodynamics, the author Joseph Katz calculated lap times for a generic prototype race car at Portland International Raceway factoring in grip and drag. Since the drag force is proportional to the square of the speed, minimizing drag is a primary concern in the speedway setup. In aerodynamics, the lift-to-drag ratio (or L/D ratio) is the amount of lift generated by a wing or vehicle, divided by the aerodynamic drag it creates by moving through air. With the increase of attack angle, CD is increasing for all cases expect for the case when angle close to 14.5 degree. His publication "On Aerial Navigation" in 1810, marked the beginning of the science of Aerodynamics. Most teams spend a lot of time and money deciding how much downforce to use verses how much time is lost to drag. Four graphs of Drag & Lift coefficient vs angle are plotted for the specified velocity range from 60 km/h to 120 km/h. Lift may also be largely horizontal, for instance on a sailing ship. which is particularly important at the upcoming Italian GP at Monza . Aerodynamic Lift and Drag and the Theory of Flight . If we look a front wing for example, which produces say 10lbs (4.53kg) of down force at 40mph (64.3km/h).If the same wing increased speed to 80mph (128.74km/h), the amount of down force generated would be 40lbs (18.14kg). When Matt Kenseth took the win on Sunday, it ended another 400-mile test session that NASCAR implemented a different rules package than what was used to start the season. That comes from a two-headed, but singular, conundrum that every serious sports car faces – balancing downforce vs drag perfectly. Enter your email address to follow this blog and receive notifications of new posts by email. This leads me to the following thoughts: On any other track I’d guess that maximizing downforce is the right thing to do, but I’ve raced down the front straight on this track (which is nearly a mile long), and the results are surprising. The CAD geometry is freely available at SimScale as well as the set of instructionsthat will get you through all the steps of setting up a case, from the mesh generation to the post-processing of results. The factors with the greatest lap-time influence are grip, power-to-weight ratio, downforce-to-weight ratio, and drag-to-power ratio, so aerodynamic performance really matters. Fill in your details below or click an icon to log in: You are commenting using your WordPress.com account. The main design objective, in terms of aerodynamics, is to maximize downforce and to minimize drag. Magnetic downforce gives the car more speed and stability through corners. View image | gettyimages.com.