The Art of Engine Cooling: Designing Ducting Systems for Optimal Performance 

Hhahaha yeah, it's a lot like moist

@Richard Bonnardel, Thanks mate

Thanks a lot, I'm happy you enjoyed it

Thanks a lot

Thanks, I'm happy you enjoyed it

Thank you labia licker 😀

Thanks, Julian Edgar has some great videos!

Thanks! I have some ideas for new vids, just need to find some time

Thanks mate, let us know how you go

Thanks Legend! I'm currently working on a video that partly looks at this, but from what I have learnt so far, in front is your best bet. There is a high pressure region around the back which flows over the top of the tyre, whereas up front there is a low pressure region. You would also be dumping hot air around the brakes, which isn't good for brake cooling. If I was you, I would look into air jet wheel deflectors, and maybe try and position your outlet similar to how they saw the best results. Just incase you don't know, they eject a stream of air just in front of the wheel at different angles to help with wheel well drag, I think 45 degree angles have seen better results than 90 degree for overall car drag, but have a trade off with a slight increase in lift. But depending on what you are doing with the car, you can reduce the wheel well lift fairly easily with some mods. Also by dumping it in front, it should leave you some room to run ducting to your brakes, or at least make it easier. Let me know how you go

Thanks mate, if you get a chance, it would be great to see a video about your design

Thanks a lot for your feedback mate When I said it is high pressure, I should have said relatively high pressure, relative to the top side of the car. For me, I like to think about these types of questions as if the air is flowing and the car sitting still. So as the air flows under the car, it has less distance to travel, it goes slower, and therefore it's pressure is relatively higher than the top, but as it is moving, it's lower pressure than the undisturbed air. I'm not an expert in this, I'm not 100% sure I am picturing your layout correctly, and I've only just thought about this, so don't take my answer to seriously. But I would think air from under the car would have the highest pressure. I'm thinking this because the air going under the sill is being moved in two directions and as it rolls around the edge would be more likely turbulent or is more turbulent, but this is just my thinking. If I understand correctly, given that the radiator is on an angle of just 10 degrees, and with the extra 3" clearance, you have an opening of about 300 inch^2, which is about 30% of your radiator size, so i'm not sure you would want to duct the inlet side or you might not be getting adequate air flowing to the face. If I was you, I would look at improving the ducting on the backside, helping to increase the pressure differential. From there, once you have that pretty good, then I would start thinking about the inlet ducting, but i wouldn't want to decrease it by too much. I would also focus on the back side as it's exposed anyway, so why not build your radiator shield into a outlet duct. Let me know if this helps, or if I am confused, it's hard without seeing the car or having a picture

Depending on your specific setup, you may be better using the bottom mounted fans in 'pusher' configuration, and running the ducting to the rear of the vehicle to benefit from the lower pressure area there.

Thanks for watching and for your insights. The internal drag is just the drag created as the air flow through the system and interacts with each of the components

Hi thanks for watching, dimensing a radiator is quite a tricky task, given all of the variables. Most people just use a rule of thumb and select one that is capable of disipating 1.5x the engines output. That would be a safe place to start and then you can look at decreasing the size of the radiator or choosing a different radiator design, whilst modifying the ducting and fan size for a given track and that days temps. Unfotantely it can be a costly and time consuming exercise. I'd suggest looking at others who have a similar car and drive under similar conditions, and asking them for advice, how there system is going, and what they would recommend

Thanks a lot! You are right, at the bottom of the windshield there is a low speed high pressure region, but the air going over the car is high speed low pressure whilst under the car is reletively slower. the same amount of air needs to flow over the car as it does under. The flat bottom makes under the car a short distance. Going over the car it needs to go over the roof, so the distance is longer, to travel a larger distance in a given time means the air traveling over the top is relevatively faster than under the car. The key term is reletive. All air passing over or under a car is traveling faster than the air infront or to the side of the car. I hope that helps

Thanks, I'm glad you have enjoyed it. I don't know the ha36s alto very well, but having a quick search on the internet and i found this upgrade kit "S.W.K. SUZUKI WORKS KURUME SPORTS INTERCOOLER - ALTO WORKS RS HA36S", this looks really good, tight space, curved edges along the top and channels it well into the intercooler. I wonder if instead of the sharp 90 degree just after the expansion point to meet the bottom edge of the intercooler if this couldn't be tappered to allow for a gradual change of direction, reduce any eddies as well as increase the chances the air flow stick to it, increasing the usable surface area of the intercooler. I suspect this may have increased the difficulties in manufacturing, but if you're able to create your own, I think this is an excellent base to start testing and playing around with. Let me know what you end up doing

Thanks. I don't own one. I just like to design and make improvements on paper in my spare time. I thought due to the boxy front end it would be a good challenge to see how much it could be improved. Swk and KC technica both have great solutions. Thanks for your input, it helps me see thing's differently. I grew up building RC planes, so aerodynamics fascinates me.

That's a cool hobby, I do similar things in engineering and finance for fun. I'm glad I could help a little

Thanks mate Could you split the opening into two or three, reducing the amount of degrees for each section? I think convex is the best, it helps to keep the air stuck whilst allowing for a large change in opening over a short distance. But where each of the walls meet I would have a sharp intersection point. If possible, concave close to the radiator as it will help to allign the flow path with the radiator core Expanding on the walls as well or alone is definitiely a good option, I think papers stick to just the verical section as it simplifes the study, but anything that happens in the vertical should also happen in the horizontal. I'm not sure how much it impacts the total allowabe degrees, but would be very interested in reading anything you find or of any results you see

@@thefastandthenerdy Not really found much more on this other than a few people mention Kuchemann & Weber, and their research "Aerodynamics of Propulsion". There's a guy who mentions a KW duct for an oil cooler on his aeroplane, and another paper on wind turbing diffuser Aerodynamic study with Openfoam. My toughts are still to use a rocket nozzle with a 15deg angle but drawn using parabolic/bell approximation (theres a video on how to draw on youtube) but flip it in the x and y planes so that I have a gentle spline with the very last portion (what would be the converging section of the motor) against the rad face. I might actually get round to it this summer.

Awesome, let us know how you go

Hi, Thanks for watching. I don't think there would be much you could do, a small box around the radiator might help, but you'd need to make sure that it will still flow a good amount of air in all positions. I would suggest experimenting with different lengths to see if there is anything that can be done to help

Thanks, I hope you are having a great day

Hi, thanks for watching. Your car would have been designed for the conditions you are driving in. Assuming your not racing it and everything is working ok your current system should be more than enough. If you however see the temps going above what you are comfortable with, I'd recommend seeing a mechanic. If you're looking to reduce internal drag, then ductin could help, but I don't think it would be worth it unless you really enjoy building this sort of stuff, measuring, and experimenting

Hi, that would be really cool to see, especially on a land speed record car. It's my thoughts that the meredith effect isn't used to produce thrust in cars for a couple of reasons, 1.We would need to design the outlet for a certain speed. We could overcome the sizing issue at other speeds by using an active outlet, but we are adding cost and complexity to the system 2. It is very sensitive to boundary layers. That's why the under body duct on the mustang worked better than the wing duct on the spit fire 3. Unlike a plane, in most examples we would need to eject the air into air that is being used somewhere else on the car, diffuser if exited under body, rear wing if ejected above the car, wheel well pressure if ejected near the wheel, so we need to condiser that impact on the whole body's aero. This could be somewhat eleiminated if the radiators are at the back, but then we need to think about packaging, weight balance etc. 4. The effect on a car could be increased by adding some exhaust gas into the exit ducting, but I think the benefit of reducing drag isn't as great as increasing the downforce by putting that exhaust gas in the diffuser. Most races are won in the slow corners not in the straigts or the high speed corners, so any increase in downforce is usually better than a reduction in drag, obviosuly that's not always true 5. Given all of this, the ability to just offset a large amount of the cooling drag is a massive advantage when it comes to racing without needing to go too complex. It's my opinion that aeroplanes are at an advantage when it comes to taking advantage of this effect, the fact that cars are close to the ground hinders the designers ability to use it. But also cars go through a large range of speeds and winning in a race car doesn't usually come down to who goes the fastest in a straight line, whereas the being faster than the person you are in a dog fight seems to be more of an advantage, but you'd need to speak to someone else about that. Keen to hear your thougths, especially if you have found an example of a car that does do this or if you have done any experiments yourself

Hi, Thanks for watching. I'm not across your regulations, but I'd go for the GT40 style bonnet to exit the air

Great question, can you move the radiator? might also help with weight distribution, but not always an option. I'd also look into if its possible to extend the intake and allowing the top angled section to do more of the heavy lifting. Or maybe you could add onto the lower intake to create an angle, make something out of cardboard to begin with and do some testing with a fan. Other than that I'd look into either changing the radiator and or modifying out the exhaust duct. You still have lots of other areas to explore and have fun testing

@@thefastandthenerdy Can i send you message somehow, one option i considered is just angle or rotate the radiator forward which would help with the angle but it could it not create other problems? The roof and floor would be different lengths doing it that way.

Hi, angling the radiator is a great idea, f1 have been doing it for years and it's been quite successful there. I'd be happy to help, send me an email at trmays86@gmail.com with some photos and what you plan to do and I'll try and find some time to discuss it with you.