– There’s no doubt that aerodynamics have played a huge part in the improved lap times that we’ve seen here in the cars at World Time Attack. There’s a misconception though that developing a proper aero package requires an F1 budget. We’re here with Andrew Brilliant from AMB Aero, and we’ll find out how developing an effective aero package isn’t outside the realms of the average club level competitor. So Andrew this is something that we’ve seen becoming more and more prominent with World Time Attack cars as well as motorsport obviously all around the world. Can we start though by going into your background a little bit, how did you get involved in aerodynamics? – I kind of fell into it. I’m not actually trained as an aerodynamicist, but as a mechanical engineer and then I was in motorsports and then we started just finding lap timing, these little things and I’d always loved fluids and you know had a reasonable aptitude with computers. So I just started experimenting and learning a lot and then it became my profession slowly. It turned from a hobby to working with other professionals and then just became a full time business actually. – So if you want to get into aerodynamics these days, are there specific courses that people can take at university level to train or do you have to sort of self train if you wanna look at motorsport aerodynamics? – Yeah no so there’s a couple of respected aerodynamicists around here that run courses. We had one in Australia but we haven’t had a venue for it for a little while but there’s a guy named Scott Beeton who has an online one, you can search him out, AeroDesign. And then also Sammy Diasinis, I think I pronounced that right. He’s a lecturer at I think University of New South Wales. He’s a designer at Porsche and they’re both solid guys and so those seminars are definitely out there. There’s plenty of books on the subject although they’re not as in depth as you know the knowledge that’s on the high end, they’re good introductory courses. – So as essentially you got into aerodynamics, and found speed in the cars obviously you’ve developed that angle and I think this is something that maybe is overlooked when it comes to getting speed and lap times out of cars, there’s a few areas we can go into, obviously engine performance is generally an easy one, there’s also working on suspension and mechanical grip from the car, and then of course we’ve got aerodynamics, obviously if we want the perfect result, we need all of those working together. But in terms of like factoring the importance of aerodynamics from your view. How does that sort of rate with the other two areas in terms of what’s most beneficial? Like if you had to choose one of those three, what’s gonna give you the best improvement from your car? – Yeah that’ll vary a lot car to car and team to team because how good do they have each of those categories? But they do enhance each other. You know like the suspension vehicle dynamics is a magnifying lens for the aero and you can change how the aero works so much with the vehicle dynamics. So understanding those interactions is really important. At this level I mean as you saw in Time Attack, if you look back in 2009, 2010, nobody was under one minute 30 here. And the basic specifications on the cars have not changed a lot in terms of their, maybe some of them got lighter, some have got heavier because they added aero where they didn’t use to. Suzuki for example is more than 50 kilo heavier than he used to be with aero but much faster. But the whole field’s moved into the low 20s from the low 30s and I think aero is one of, if not the major factor behind that. The tires have been the same, actually they started making more power too recently, Billet engines have made a difference. I mean that’s not adding up to nine seconds or whatever. – I think there’s probably a general belief out there in the market that if you want to develop real aerodynamics packages for your cars, you’re looking at spending huge amounts of money, and this may be off-putting I think. Obviously aerodynamics when we think of it from a layman’s perspective, we’re looking at the F1 teams and the sort of budgets these guys have. But it’s possible to actually achieve a really effective aerodynamic package, even at a club level, would that be fair financially? – Yeah I mean I don’t think that’s the case at all and I think when we first started doing aero for Time Attack it had that misconception and people were like oh this has all gone too far. And I completely disagree with that because compared to what teams spend on engines I think aerodynmics certainly can be inexpensive and I can give a few concrete examples of that. You know like the first Time Attack car that I ever did was this NSX in the States that ended up becoming the champion and taking this year’s serial lap record. And that car had an aero build budget of I think $350 of sheet alloy in a shed and we ended up going 3.5 seconds quicker like that. There was no CFD it was just like what the team knew and what I knew and our fabricator didn’t sleep very much and that’s what we came up with. So I think you first have to wipe it out of your head, that there are shapes that have to be perfect, like a wing is a really fine tuned shape, and then there’s some things that are like taking a sledge hammer to the car and making a really big impact just because people don’t understand how it works, and bringing that knowledge level up, training the teams about how to use that aero will make a big difference as well. So I think another example would be like Nick Ashwin, or Under Suzuki, or even Andy Forrest where they’ve built their own aero. So they’ve taken so much of the cost, like the raw material cost is not that much. And the design cost is not that much, it’s getting it built that’s expensive. And if you take on that attitude, I think composites are new to this group. Everyone’s been fabricating for a long time. Like Andy Forrest and their team, they got on YouTube, and they got videos about how to make carbon fibre. I got a long list of teams that learn how to make their bodies on YouTube. – So I think the point here is AMB Aero, you offer a consultation service. So it’s not a full house, or it doesn’t have to be a full house service where a team drop off a car, come back, write out a massive check, and pick up the car finished with a full aero package attached, you can work in a multiple different ways including just providing some consultation, telling the teams what they need to do, and then allowing the teams to actually implement those changes themselves and that can be quite a cost effective option? – Yeah I mean we have an entry level package designed for those teams, that was the point of what I wanted to do when we founded this business with my partner was that we wanted grass level people to be able to do aero, and for it not to be this thing where they’ve built a bunch of stuff that didn’t do anything. But to give them a proper aero build of some kind. And we wanted to do that for every budget. So we start at you know $2000, we have packages for $2000. There’s a customer that had made a video that’s out there on the internet as well. If you search about that, you can find a lot of stuff. But then we’ve also got mid range stuff, you know $7500, $15000. If you wanna be in the Under Suzuki, MCA, Andy Forrest level stuff, yes that’s a significant design cost. But still pales in comparison to production. – I think straight away those numbers you’re talking about, starting at USD$2000 for some consultation is probably a lot cheaper than most people are thinking. I mean that probably is comparable to what a team is spending on a set of tires and you’re getting a real world advantage from an aero package that then they can go and implement themselves. Let’s talk a little bit about your actual design process when you’re faced with a fresh car, one that you haven’t working with before. So what’s the first step if you’ve got a team that has a reasonable budget, and they want you to develop something that’s actually gonna be really effective at maybe the pointy end of the pro class here at World Time Attack. – Yeah so I think the fundamental principle of the design will all be catered around the team firstly. Who’s building it, who’s driving it, who’s managing the program, and it’s quite custom to each of those factors. Like we could do two of the same platform in a row and the car will be very different because we think very much about what’s realistic for this team to build. And if we go and design something that an F1 team can manufacture, and it’s some guy in a shed with his mates, that’s not gonna happen. So you have to be I think really diligent about catering it that way and that’s why you see such a big diversity of our packages, like you’ll see us go from nemo to scorch and they’re so different. You basically really customise it to those factors. And we can even tune the aero to be more or less sensitive so it’s got more peak downforce but harder to drive because a pro might be able to do that but an amateur cannot. We have some many things we think about that way. – In terms of dealing with developing that package and giving the team a model to work with or the shapes to work with and sizes et cetera, you’re starting by actually digitising the car, correct? – Yeah, yeah so with you know, the entry level package is more just what we call best practice, is where we look at the car, we help them figure out how to make sure it cools and works better aerodynamically. And then from the middle package on up, which we call our Time Attack Pro Racer package, obviously we have packages outside of Time Attack, so those are where we start scanning the car. So usually I’ll fly in myself ’cause I wanna spend time with the team and teach them about aero. And at the same time we do that, we 3D scan the car and then take that back to the office where we process that and turn it into the 3D model that we use for CFD or wind tunnel, or whichever thing they’re gonna do. So talk to us a little bit about CFD because that’s something that’s obviously become more prominent as computing power has increased. Obviously reduce the cost and development time of aero so how does that process work? – Yeah that’s actually, I mean I might be going off topic a little bit, but that’s been so fascinating to watch because the way computer power has changed over the last 10 years is what’s made that now accessible. So that’s really changed the landscape of CFD now, because now these small companies can spring up that are able to do this high end development, that used to be totally impossible, ’cause you had to have a data centre sized super computer to do, to even dream of it. And do that’s what’s possible now and we’ve become half an IT company in a way because we’re just constantly building machines and maintaining them. But CFD’s very powerful, it has its weaknesses, but it has its strengths that the cost is there, and if you can dream up a shape, you can draw it and you can test it, you don’t have the physically build this thing in real life like you do in a wind tunnel. – So massively reducing the development cost because when you finally go through the process of making a physical part, you can be pretty confident from the CFD results that that part is going to give you the results you’re expecting? – Oh yeah and the quantity of tests you can do. So I mean there are some things that are faster to do in a wind tunnel like adjusting a wing angle for example, you know CFD that’s another run. But we could test so many parts in a week in CFD that you could never dream to do in a wind tunnel. Just stuff that’s out, you think of something out there and you learn from it and that’s still impossible in a wind tunnel without a team of 50 model builders. If you tried to match I think how many crazy things we could test in a day, you’d need a hell of a model team in a wind tunnel. – In terms of validating the results that you’re getting from CFD, when you do have the opportunity to work with a team that has a budget for wind tunnel testing, I mean typically how well do the results from the CFD analysis line up with real world downforce results? – I would say that our CFD is lining up probably with one exception that we’re still getting to the bottom of, but with the exception of that one car, historically we’ve been closer than the wind tunnels were to reality. So far, most wind tunnels. Now there are very good wind tunnels out there, you know $20000 a day wind tunnels, but there’s a lot of wind tunnels that are so so. But those things are actually not important and we don’t worry so much about that unless we find a hole in what that wind tunnel sees, we look at relative accuracy, not absolute accuracy. Absolute figures, I believe should only be derived from a measurement on the real car. We look at a CFD gain value and we’ve learned to trust that and there are some things we’ve learned about CFD we know yeah that’s kind of the boundary of CFD. But the wind tunnel’s the same way, there are certain things the wind tunnel will tell you wrong. And there are times when they’ll contradict each other even. And having that depth of knowledge, that experience, you can just stay away from that kind of a design and that doesn’t mean you’re giving up something because you just spend your time developing other things you know are accurate. – I wanna delve a little bit further into the wind tunnel, but first of all if you aren’t using the wind tunnel to validate your designs, how do you validate those in the real world, how are you getting the results off the car at a racetrack? – Yeah well we do do wind tunnel validation if the customer budget allows. But most time attack teams, we’ve only had a few exceptions to this, did not have the budget for CFD to wind tunnel to on track and we were the first to do all three together but that’s quite rare. So we do rely a little bit on the data we’ve gathered from one car that’s managed to do that sort of correlation project and we have to sort of apply it everywhere because the budget just doesn’t allow for that. But we do push really hard for all of our teams to instrument the car at least in some way so that we can validate the data. – So we’re talking here load cells in the suspension system? Yeah load cells, shock pods, ride height sensors. And there’s ways, like I mean there are really primitive ways that you can do this if you’ve really not got a budget, I mean when I started out racing my own car and Bonneville stuff, you know we’d go out on the dry lake and we stuck zip ties on the shock shaft and did a coast down test. It’s rough, it’s rough data, but data’s data. We were able to make a car that was unstable stable that way. So that’s a win and so I don’t think, I would never tell a team to not test because you don’t have the ultimate way to test, you’ve gotta validate any way you can afford to do. But it’s not really that expensive in the picture of building a car to put four shock pods on there. But the really important thing is the process. I cannot stress enough how difficult it is to do that process properly. Even if you have the sensors, we get customers come back with data, and they’re like oh the downforce isn’t there and then this happened really recently with a customer, and we’ve just forced them to put it on the scales and then load up the car incrementally and then see what the actual curve laid out as, and it was drastically different, it actually lined right up to CFD where for a year they’d thought they were missing downforce. – So essentially if you don’t know how to analyse the data that you’ve got then you’re just guessing. – So that’s a big part of what we try to do is to get teams to measure as good as we can. It’s ideal when you can sit with them through the testing but that’s not always realistic so we try to train ’em and we give documentation to them about how to do that the best they can. – OK let’s just move back to the wind tunnel testing because obviously that’s another area where we’ve grown up seeing that being sort of related to F1, that sort of level. But you were talking to me earlier about model, part scale testing that can be affordable for the teams who are at the pointy end of a semi professional motorsport such as World Time Attack. Can you talk us through how that works? – Yeah so there’s a technology that we kind of, I hope we pioneered it, I dunno who else is doing this. I mean Suzuka, my partner slash mentor, had this idea that most of motorsport was using too big of a scale for what they were doing. And I think that this was all based on what markets they’re selling to. Like if you’ve got, OK 50% scale wind tunnel, 60% let’s say, that’s a standard kind of scale wind tunnel. – Just to step back there, so for those who aren’t aware, what we’re talking here is a scale of the size of the car, so a 1:1 obviously we’re taking the actual car, running it in the wind tunnel, but that gets very costly, the wind tunnel needs to move a huge amount of air, hence the wind tunnel becomes more expensive, so it becomes cheaper if you’re using a scaled down tunnel with a scale model of the car, so that’s what we’re talking about. – Yeah exactly and it’s the cost of building the models and the parts to test. If you went to a full scale wind tunnel 1:1 You have to physically build in full scale, every single part you’re going to test. How many parts can you test in a day? That’s really hard, and you have to plan out ahead to build all the parts you’re gonna test. You can’t be guided by testing, you can’t get feedback from the testing. And so that becomes very very difficult to do. Now if you move to smaller scales, you start getting new technologies coming in, such as 3D printing. You can 3D print parts, they take less time to construct for various means. They don’t have to be as rigid, because they’re taking less load in the smaller scale. So the cost of wind tunnel goes up at the cube of the scale. So it’s really a high, you know it gets really nasty at the high end. – And when it comes to that small scale testing though, the accuracy of the model becomes more and more important. You were talking to me earlier, one of the issues, one of the important issues with aero is the ride height, and of course when you scale down the model, those ride height changes become more and more precise, so can you tell us how that works? – Yeah I mean every single dimension on the thing becomes more and more high precision as you get to the smaller scale. So that part’s difficult. And that is part of what you accept as your plus/minus, allowable plus/minus and how true you think this model shape is to the real car. Well you know we integrate 3D scanning back in, so we have like a smaller scale, really high accuracy scanner, we scan the models back in so we get a better feel for how far off these things are. But you still struggle with those kind of things at small scale. You know what the problems are, what the shortcomings and the difficulties are, and then you use it for what it’s good at, and when it’s not good anymore you move onto the next thing, and that is a much more efficient process if you do it that way. – Now you mentioned that some of the large 1:1 scale professional tunnels, you’re sort of talking $20000 a day or more, if we’re looking at some of these cheaper scale wind tunnels, can you give some indication of what a day testing on that wind tunnel might look like? – You mean like cost wise. Oh there’s a bunch, like I dunno in Australia, but I know like in North Carolina they have some of these ones like the NASCAR guys use, and they’re really inexpensive. You know you could go there for like two or four grand. But there’s no moving belt in them. So there are some things you can trust and some things you can’t. I mean you don’t have a moving belt. If your team is looking at trying to make this figure out the cooling system or the rear wing you know you might make major imporvements in a tunnel like that so you never rule it out and say oh that testing’s bad testing, forget it. But you gotta know what it’s good at. – OK I wanna move on and talk a little bit about the aero balance of the car. So I mean again from a layman’s perspective it seems like it’d be a relatively easy task to go and put a big wing on the back of a car and make a tonne of downforce at the rear of the car, but of course that’s going to affect the balance of the car because we’ve only looked at the rear. So obviously in order to make the car work correctly, it’s important to balance the downforce from the front to the rear. So how do you go about doing that and obviously, CFD you’ve got some ideas there, what can you do to allow that to be adjusted in the real world to suit the car and the driver? -Yeah I mean there’s so many strategies for how you do this and we cater it a lot to the car and the team but the basic concept in Time Attack is we give them an adjustable rear ring, and then we have a CFD value that we found that most drivers are happy with and we sort of float around that percentage. And it’s based around the weight distribution of the car. So there’s a percentage variance from that which is a driver preference or a team preference. There’s a lot of complex factors going on like how the car is actually changing its attitude dynamically. Like what it’s doing in yaw, roll, pitch, and there’s so much complexity to that and we’re learning, we learn every day about this, today especially. We’re still learning right. And that’s the point why we come out here is to try to find out those kind of things. But we get that percentage smaller and smaller every time. And the tighter we’re able to make that adjustment window as we learn more, then the more we size the wing appropriately and then they end up being more efficient. That’s one of the ways we can make the wing drag less because we don’t have to make it able to have an extra 20% rear we go no no this is fine tuned right for this number. – OK the other thing we see with the high downforce cars is it adds a complexity to the suspension design because you’ve got a car that has obviously zero downforce when it’s sitting stationary, as the speed increases the downforce also increases which tends to compress the suspension so particularly when we’re getting cars here that are getting sort of 280 kilometres an hour at the end of the front straight going into turn one, this compresses the suspension down. So how are the teams best to deal with this? Do we run higher spring rates and compromise the suspension system, run it on the bump rubbers, or third spring and damper set ups, what’s your preference? – Well to me I mean obviously a third spring is a much better situation because you have a heave control system. And that’s really what you’d want, I mean short of an active suspension or something like what Andy Forrest has got where he’s got an actual, you know he’s affecting the length of the push rod dynamically on the third. – Yeah no we looked at Andy’s car. He’s got a little air canister, I don’t believe that he’s actually using it yet, but ultimately it will be able to change the ride height at speed essentially. But yeah in most instances the third spring or heave spring is the best arrangement. If we don’t have that, what’s your second best? – The second best is gonna be, you’re gonna have to use some combination of bump stop and spring right. Because what you’ve got is if you make the car rigid enough to endure turn one without using any bump stop whatsoever. Then with the kind of air load’s we’ve got now, you’re gonna wind up with this spring rate that’s way more than the tire spring rate. Which means that all the energy being fed into this car around the racetrack is going into the tire. And you see the teams now are working on trying, some of the teams that have more downforce, are working on trying to ride this limit of tire versus failure. And either one of those things will contribute to it. Because they both feed energy into this tire, and cause it to overheat or to damage the side wall and come apart. So with the third spring set up like Andy’s, that’s just letting you control that so you’re able to make a car that’s softer for a greater percentage of the lap and the time when the car is really rigid is less. And that’s the basic concept. With bump stops, you can do that, but not as well, because inherently, let’s say you tuned it, you said OK I wanna use the bump stops only on the straight away, then you can, you have to have a ramp rate, like you can’t make it just instantly go to one or the other, the car’s difficult to handle. So you now like high end of motorsport, you’ll sit in a room full of engineers, and this is all you do all day, is looking at an air map, and looking at the suspension and going, how do we get more aero out of this car and not blow up tires, and not make it difficult to handle, and that’s how prioritised aero is at the top level. And this is becoming that way. So there’s no solid answer about this, it’s gonna be, you’ve gotta get somebody good that knows when they’re doing with that stuff, and they’re gonna be constantly tweaking that and changing it track to track. – So essentially, long story short there, we’re always going to be focusing on a compromise if you wanna get that aero and make the suspension and the aero work together? – Yeah, yeah and then you’ve gotta have good aero too, like if you have no idea what the aero’s doing, what are you doing with the suspension? So it’s important to make that work as a package. That’s what the top end of the field will be doing moving forward and you see that, you see that happening now. – Another common myth, or I dunno if it’s a myth, I wanted to get some answers on this, another common thing I hear is that aero doesn’t really produce any downforce until the car’s perhaps up around 100 mile an hour, sort of 160 kilometres an hour. Is there truth in that? Obviously the aero downforce does increase with speed, but what sort of speeds can we start getting really useful increases in downforce? – That depends on how much downforce you’ve got. Right if you’ve got a car that’s got mega, mega downforce in the slowest corner on this track, so like our highest downforce track out here today in the slowest corner here, has twice as much downforce as a GT car does in a high speed corner, you’re gonna feel that right. And if you look at the trend, people have that misconception, and the evidence I would give to disagree with that is if you look at the top end autocross hill climb, all those cars, massive, massive aero. And it’s really important for them. So yes the speed’s lower but then they’ve put low speed aero on it and it’s just as important as anywhere else. And if you look at even really tight courses, you look at like Formula SAE. Those are the tightest courses there are. Super low power, super tight courses, mega aero. And it’s a percentage of the lap time. For them if they gain two, three tenths on aero, it’s the same things as gaining a second and a half here, ’cause the course is only 30 seconds long. – So essentially the speed, you’re just designing the package to suit the speeds that the car’s gonna be seeing. – Yeah just changes your drag curve, and we look at that in simulation. As we go through our test runs and we look at it in our database and then we see how much drag we’re picking up and we run simulations on the change in downforce and the change in drag and we make sure that we’re always on the right side of that curve. And sometimes we try to be a little low drag more than that computer predicts, we think that’s the right way. But you have to calculate these kind of things. – Look Andrew thank you for the insight there. I think hopefully that’s dispelled some of those myths that proper aero is only in the league of those with million dollar budgets. And if people do wanna find out more about you, maybe work with you, how can they get in touch? – Yeah you can just go onto our website, it’s amb-aero.com – Alright thanks for the chat Andrew. – Yeah no problem. – If you liked that video, make sure you give it a thumbs up and if you’re not already a subscriber, make sure you’re subscribed. We release a new video every week. 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