Ask Slashdot: Why Did It Take So Long For Cars To Become Aerodynamically Shaped? (autoblog.com) 212
Here's what dryriver wondered after hearing that the oldest Porsche T64 in the world -- built in 1939 -- was going to be auctioned:
What stands out about this nearly 80 year old car is how curved and aerodynamically shaped it is. If you then Google 1950s, 1960s, and 1970s car images, you find that they are nowhere near as aerodynamic in shape. It took a while before production cars started to appear en masse that had a nicely-curved aerodynamic body, and before Bezier curves were invented, which allowed early CAD software to produce precisely curved designs.
Why did it take so long for cars to become more curved if aircraft of that time already had aerodynamic curves and the benefits of an aerodynamically shaped land vehicle were also known? Was it an issue with actually manufacturing curved cars in great numbers below a certain cost level, or did the automotive industry simply not care about the aerodynamics of their vehicles for a long time?
Long-time Slashdot reader MightyYar blames cheap gas, arguing that "When gas was nearly free, there was little incentive to make vehicles aerodynamic." (He also complains that "When they did go aerodynamic, they all started to look the same -- as there is an optimal aerodynamic design for a box on wheels so every designer with the same cost constraints and design tools will converge on that.") Z00L00K adds that "Until the 1930's aerodynamic drag wasn't really an issue for vehicles because the top speed wasn't that high and the roads didn't really permit high speeds either."
Long-time Slashdot reader Martin S. believes "Styling for public tastes beat aerodynamics except for outright race cars. Fuel efficiency has only become the primary driver with the rising number of cars, pollution levels in our cities and climate change." But are there other pieces to the story?
Share your own thoughts in the comments. Why did it take so long for cars to become aerodynamically shaped?
Why did it take so long for cars to become more curved if aircraft of that time already had aerodynamic curves and the benefits of an aerodynamically shaped land vehicle were also known? Was it an issue with actually manufacturing curved cars in great numbers below a certain cost level, or did the automotive industry simply not care about the aerodynamics of their vehicles for a long time?
Long-time Slashdot reader MightyYar blames cheap gas, arguing that "When gas was nearly free, there was little incentive to make vehicles aerodynamic." (He also complains that "When they did go aerodynamic, they all started to look the same -- as there is an optimal aerodynamic design for a box on wheels so every designer with the same cost constraints and design tools will converge on that.") Z00L00K adds that "Until the 1930's aerodynamic drag wasn't really an issue for vehicles because the top speed wasn't that high and the roads didn't really permit high speeds either."
Long-time Slashdot reader Martin S. believes "Styling for public tastes beat aerodynamics except for outright race cars. Fuel efficiency has only become the primary driver with the rising number of cars, pollution levels in our cities and climate change." But are there other pieces to the story?
Share your own thoughts in the comments. Why did it take so long for cars to become aerodynamically shaped?
Because it didn't really matter (Score:5, Interesting)
People didn't really care about cars being aerodynamic, they wanted them to be practical and look good according to current fashions. When buying a car they would rarely factor a 5% fuel saving in, especially if it meant that the car was an awkward shape or lacked storage space.
Lately things have started to change a bit with electric vehicles and our greater ability to optimize the shape of the car with computer simulation. Cars can look fairly normal but also be optimized for airflow now.
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Re:Because it didn't really matter (Score:5, Insightful)
People didn't really care about cars being aerodynamic, they wanted them to be practical and look good according to current fashions. When buying a car they would rarely factor a 5% fuel saving in, especially if it meant that the car was an awkward shape or lacked storage space.
Lately things have started to change a bit with electric vehicles and our greater ability to optimize the shape of the car with computer simulation. Cars can look fairly normal but also be optimized for airflow now.
I don't agree. One of the first purpose designed fighters, the Albatros D.I [wikipedia.org] was wind tunnel tested (this is in 1915) to wring every possible bit of performance out of the engine and the same basically applied to race cars from very early on. I think although people knew aerodynamic shapes really helped with performance from very early on, an aerodynamic shape didn't really matter for a long time because gasoline was dirt cheap and you could just throw horsepowers at performance problems so you didn't really have to think all that much about an aerodynamic shape. Given those economics, slab sides were cheaper than beating out complex, curved aerodynamic panes. It was only when you began to want really high levels of performance and especially when you wanted that combined with fuel economy that aerodynamics became an issue and the 1973 oil crisis added that extra impetus for the car industry. You can see the emphasis on streamlining very early on in race cars, Bentley for example kept throwing more horsepowers at the problem of reaching ever higher speeds in race-cars (with the aerodynamics of a tractor) until they reached the limit of where the remedy of simply adding an even bigger monster of an engine each racing season can take you, brute forcing just wasn't enough anymore. Just compare clunky Bentleys of c.a. 1928 - 1930 or the Alfa Romeos and Bugattis of the early 1930s with the Auto Union silver arrows of 1933 (Particularly the aerodynamic C model [wikipedia.org]), it's like comparing a 40 foot container with a Learjet. The Germans went for streamlining and compressors for extra performance, which is what we are still doing in internal combustion powered cars today although the physics of automotive aerodynamics weren't fully understood until the 1960s (beginning with the Lotus 49 [wikipedia.org] and its aerofoil spoiler).
Re: Because it didn't really matter (Score:4, Insightful)
Don't forget that most roads at the time were either cobblestone or dirt roads, so high speeds would shake your teeth out.
Better having a practical vehicle with room to transport yourself, family and cargo in reasonable comfort.
Re: Because it didn't really matter (Score:4, Insightful)
It still doesn't matter for 99% of most cars.
Vehicle aerodynamics only really matters above about 50km/h (30mph) and most driving is done well below this.
Simply rounding the corners of a box is sufficient at lower speeds - hence designs like the Nissan Cube can be shaped like they are and have virtually zero effect on urban cycle mileage - these cars are not intended to spend any appreciable amount of time at higher speeds, so why design for it when doing so impinges on the practicality of the carrying capacity?
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I get your point, but your example is bad. The Nissan Cube has a .35 drag coefficient...the same as a Dodge Viper or BMW Z4.
https://en.wikipedia.org/wiki/... [wikipedia.org]
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Wind tunnel testing is not a substitute for computer simulation. For example, take a look at the Kia Niro EV.
There are little holes in front of the front wheels that reduce drag and noise. Developing those without computer assistance would have been almost impossible. Also look at the shape of the bonnet and wing mirrors. The original Nissan Leaf had unusual headlights which were designed to deflect air away from the wing mirrors because in an EV the noise was quite noticeable, but in the Niro they found a
You've got that backwards re. computer design vs. (Score:2)
All the summer computing power in the world is still no substitute for actually blowing air over your car. Formula 1 cars are arguably the most aerodynamically complex vehicles on four wheels and are heavily invested in CFD for their initial design work, but the definitive test is still sticking a bunch of sensors on the car and running a few laps (since wind tunnel time is heavily restricted) - https://www.formula1.com/en/la... [formula1.com]
You're both wrong (Score:3, Interesting)
Or one might say you're both right, but this is Slashdot.
The two techniques are both indispensable. It's true that the really clever gains aren't feasible without computer analysis, and it's also true that you have to go to the wind tunnel with a full scale model to verify that it really works the way you think it does.
Fuel used to be expensive, now it's cheap (Score:2)
the logic here seems wrong. Fuel is cheaper than ever right now. It used to be expensive.
But cars were for the wealthier people. They didn't last that many miles so you had to replace them more often making them even more expensive to own.
So maybe no one really cared about the cost?
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the logic here seems wrong. Fuel is cheaper than ever right now. It used to be expensive.
Fuel was cheapest in the USA in 1998.
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People didn't really care about cars being aerodynamic, they wanted them to be practical and look good according to current fashions. When buying a car they would rarely factor a 5% fuel saving in, especially if it meant that the car was an awkward shape or lacked storage space.
Lately things have started to change a bit with electric vehicles and our greater ability to optimize the shape of the car with computer simulation. Cars can look fairly normal but also be optimized for airflow now.
Not to mention that it was incredibly expensive to get access to a wind tunnel and compute power to do analysis up until recently. Manufacturers, especially of sports cars have know about the benefits of aerodynamics for years. Ferrari's and Lambos have been designed to be slippery for years, even the Muira which wasn't designed with a wind tunnel was pretty aerodynamic for it's time. Fast Forward to the 80's and you're getting cheap cars like Toyota MR2's being designed with aerodynamics in mind, now days
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I'd also argue they arn't that functional as well (not like a cargo-van).
Couldn't agree more, though they probably are pretty good for hauling things that stink, like pig shit or people...
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Here in East London, traffic is well known to go slower than when it was horse drawn. And in case anyone gets over excited, we have just had a blanket 20MPH speed limit. Not only does in not reduce accidents, it increases pollution, since the traffic spends most of its time completely gridlocked. However, its a safe bet that the next round of politicians will bring back the red flag act.
Aerodynamics is a non-is
Who says they weren't? (Score:5, Interesting)
Plenty of cars were aerodynamically shaped, and some manufacturers acheived low CDs that would be difficult to beat today - the Lotus Elite/Elan and particularly the Elan+2, where remarkably clean aerodynamically, which might be as good as has ever been acheived. . That's how they managed to go pretty fast on 120 HP.
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Or the Tatra T77 from 5 years earlier.
But on the other hand, a lot of cars that look aerodynamic are actually quite terrible, because it's not necessarily the smooth shape that is important but things like the angle of the rear hatch/door/trunk, size and shapes of mirrors or grilles.
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All of these principles are strong drivers behind the overall design philosophy behind every porsche model (with some exceptions). Which is why most porsches basically look the same. 80 years later, it's more out of blind loyalty to the company's founder than to real engineering constraints
The best design that works around a big lump of ICE is front-mid engine. The second-best design is mid-rear engine. Then front, then rear. By spending billions of dollars cumulatively on R&D, Porsche managed to make a rear-engined car that would handle well. But the Cayman outhandles the 911 if you do all the same stuff to it, so they have to put less equipment into the high-end Cayman so that the 911 is faster around a track. Meanwhile, you get the same kinds of lap times by spending half as much money
Re:Who says they weren't? (Score:4, Informative)
The original stealth fighter and the stealth bomber are all flat shapes, and not very many of them, because it was computationally cheaper to model when all you had was a handful of flat planes.
Automotive wind tunnel testing didn't become common until the eighties. This was before CPU time was cheap enough to use CFD, they had to do tests, so they figured out what was or wasn't aerodynamic by iteration. Today they can do the initial aerodynamics testing in software, and then take the model to the wind tunnel for confirmation.
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Yes and no. The Have Blue demonstrator and the F-117A "Night Hawk" were all made up of flat planes. B-2 "Spirit" is all smoothly blended curves. The difference is advances in computing power and radar return prediction software.
Re:Who says they weren't? (Score:4, Insightful)
A big part of it is also practicality. People like to criticize the overly boxy GM cars from the 80's with their stodgy formal rooflines, but in terms of practicality they provide a large, open cabin, great visibility, as well as a large trunk opening. Today's cars may be more aerodynamic, but they are far less practical. The sloping rooflines and fastback styling make the cars harder to get in and out of, harder to see out of, and the space utilization is pretty poor - the interiors are more cramped and you end up with less headroom despite the size of the cars bulking up considerably in the past 30 years. Also, have fun loading the trunk through the tiny trunk opening since the C pillar goes almost to the real of the vehicle now. It's really no wonder that people are choosing "light trucks" over the cars that are made today.
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Today's cars may be more aerodynamic, but they are far less practical. The sloping rooflines and fastback styling make the cars harder to get in and out of, harder to see out of, and the space utilization is pretty poor - the interiors are more cramped and you end up with less headroom despite the size of the cars bulking up considerably in the past 30 years.
Today's most popular "cars" are crossover SUVs, which are just tall cars. But those tall cars have lots of headroom, and upright seating positions which translate into more legroom. If you insist on having a shorter car they will sell it to you, and then you have to deal with all that stuff you mentioned. People complain about the death of the station wagon, but it didn't die, it just grew up into the CUV.
Also, have fun loading the trunk through the tiny trunk opening since the C pillar goes almost to the real of the vehicle now.
Higher trunk lines have been mandated for rear impact safety reasons. Those tall trunks stop tall truck
It was done in the 1920's (Score:2)
The inventor is Aurel Persu, but since he's not a Westerner his work is largely ignored in Wester Europe and the USA.
https://en.wikipedia.org/wiki/... [wikipedia.org]
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Looks are purely perceptive based upon past and taught experience. Why did cars look the way the did because in shape form, they were drivatives of carriages, both horse drawn and railway, plus of coarse constructive techniques of the era perferred flat surfaces, complex curves where quite complex. Keep in mind the first motor vehicles frames were made of wood. Fins on cars came from the airplanes and the curves added reflected that to, still not aerodynamic. As preferred shape evolved so cars slowly shifte
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I think you are talking about *downforce*, not drag.
The word "think" may be giving yourself more credit than due: you're not getting downforce without drag.
Not material. (Score:3, Insightful)
The difference in drag is more affected by tires and rims. These effects are what is studied in wind tunnels. The drag coefficients at day-to-day speeds for most vehicles (body alone) are not significant so styling and function take more importance in design. You can just look at a bus to see aerodynamics isn't really much of a concern and there is little benefit. We are talking fractions of a mile per day under normal driving.
At high speeds it is but not at consumer speeds. The original Porsche was designed as a race car and at a time when cars where relatively light weight and before downforce was really understood. Those designs, though sleek, also caused lift especially on cornering.
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You can just look at a bus to see aerodynamics isn't really much of a concern
By that same logic, you can look at a submarine and see that hydrodynamics is not a concern... but it is; the bus's sectional density is the real issue.
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"you can look at a submarine and see that hydrodynamics is not a concern."
If you know the problems that the Australian Collins-class subs had with noise, you're not far wrong - it was proven that whilst the original Swedish design sold to Australia might have been capable of operating submerged, the designers had NEVER paid any attention to such things as actual drag coefficients or where the water flows (turbulent flow off the bow and conning tower was hitting the prop, resulting in them being _very_ dete
other priorities (Score:2)
Getting cars to work reliably at all took a long time. Affordability versus features versus customer appeal was always a struggle. Optimizing for wind resistance was way down the priority list.
Because: CAFE standards (Score:4, Interesting)
Before the government intervened and enforced CAFE standards, there was no particular incentive or reason to make cars aerodynamic. Being aerodynamic is an aesthetic, but it isn't the only one. Duesenbergs look pretty cool in their own right.
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Correct. But once highways that could support driving speeds higher than 80 km/h (49 mph) started to become common, aerodynamics started to become important not only for fuel economy, but also reducing wind noise at higher speeds.
That's why the original Citroën DS from 1955 was such an extreme revolution: its highly-aerodynamic shape made it possible to cruise well above 80 km/h without incurring a major fuel economy penalty.
Interestingly, the legalization of flush headlamp housings under US Federal Mo
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Even Duesenberg made some aerodynamic cars. Look at the SJ 557.
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Before the government intervened and enforced CAFE standards, there was no particular incentive or reason to make cars aerodynamic. Being aerodynamic is an aesthetic, but it isn't the only one. Duesenbergs look pretty cool in their own right.
You mean besides making them fast and easy to handle.
Aero plays a huge role in speed, acceleration and handling, especially at high speeds.
This would be a great time for a car analogy (Score:2, Funny)
Bad car analogy man... Where are you in our moment of need.
Because it’s not that simple (Score:4, Insightful)
Here’s a couple thoughts off the top of my head.
1) What we look at and believe to be aerodynamic may or may not actually be optimized for airflow.
2) There are other considerations - e.g. engine cooling, passenger safety - which may not be compatible with maximizing the aerodynamics of the vehicle. Want a more powerful internal combustion engine? You’re gonna need a bigger radiator, and that generally means an increase in turbulent airflow.
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Number 1) is key for the car industry. You know what the sleek looking Ferrari F50 and the boxy family sedan that is the 1978 Ford Capri share in common? Coefficient of drag. Fast cars are still inefficient, so when you have some 500 horsepower under your hood you need to provide a lot of airflow to that engine. Additionally when travelling at speed it also helps a lot to have some serious downforce.
I challenge the premise: cars are not more aerodynamic today than they were in the past. The exception to thi
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1970s Ford Capris are not "boxy". They're quite wedge-shaped. And, with two doors, neither are they "family sedans". Were you referring to these:
https://i.ytimg.com/vi/Eegjwfck0tA/maxresdefault.jpg [ytimg.com]
Are you sure you weren't thinking about something else?
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Partially. I actually was blending 2 cars in my head. The thing is the Ford Capri as "wedge" shaped as it is was not at all aerodynamic. It had a completely flat front, and a very vertical windshield. The rear end tapering off helped a bit with "sleek looks" but ultimately the coefficient of drag isn't that neat. Another car with slightly better Cd is a Tiguan. https://en.wikipedia.org/wiki/... [wikipedia.org]
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You need to keep in mind that Cd is a number that needs to be multiplied by the frontal area of a car. A car designer can reduce air resistance by making the car lower without changing the Cd. Not sure how much that applies to the F50/Capri pair as they both look low.
As for "challenge the premise": Wikipedia has a sorted list of drag coefficients that happens to be approximately chronological: https://en.wikipedia.org/wiki/... [wikipedia.org]
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Indeed it does, but that doesn't change the result. Scroll down on the page you listed an you get the CdA of cars and it's a quite similar list. But since I assume the GP was talking about looks here with his incredibly basic question I went for Cd. But based on Wikipedia the same conclusion applies.
As for the "approximately chronological if you remove hybrid / electric vehicles which benefit aerodynamics by reduction of air intakes (e.g. the Tesla X has no front grill) then there's nothing chronological ab
Not f'n everything is caused by climate change (Score:5, Insightful)
Fuel efficiency has only become the primary driver with the rising number of cars, pollution levels in our cities and climate change."
No, not the number of cars. No, not pollution levels. No, not climate change.
Fuel efficiency became the primary driver when there was a fuel shortage and an accompanying sharp increase in price in the 1970s. You couldn't get fuel at times, and when you could you sometimes had to wait in long lines, and wait or not you paid high prices. When prices came down again a decade or so later fuel efficiency once again became a lesser consideration, aka the rise of SUVs.
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I can remember a while back, when the price of gasoline in the U.S. was $1-2/gal higher than it is now, and people flocked to more efficient vehicles. Sales of pickups and SUVs dropped which, combined with the financial crisis, did little to help the domestic auto industry. We also had the "cash for clunkers" program to get inefficient vehicles off the road (and encourage them t
Internal combustion engines not the "bad" thing... (Score:2)
The second possibility is changing the fuels, replacing petroleum based fuels with the biologically derived substitutes/equivalents. That would at least be carbon neutral. Its not the internal combustion engine that is the "bad" thing here, its basing their fuel on petroleum.
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Limitations in manufacturing technology (Score:5, Interesting)
Re:Limitations in manufacturing technology (Score:4, Informative)
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And both have traditionally taken a back seat to other concerns. Crash and safety standards didn't become a way to differentiate vehicles relatively recently in the 100+ year history of the automobile.
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The manufacturing side is right but before you draw that conclusion we need to agree that cars are more aerodynamic now than they were in the past. Looking at the wikipedia list of Cds you can see that for the past 50 years cars generally fell within a Cd of 0.31 to 0.29 without much variance, and the "chart toppers" today have lower Cd not because of shape, but because they are electric / hybrid and as such don't need to ingest nearly as much air to help cool inefficient engines.
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Recent? Seriously? Unibody is a pre-war technology.
Low speeds it doesn't matter (Score:4, Insightful)
Forget about low gas price - for the first 50 years the max possible speed was 100 mph, and most of that time the cars travelled at less than 40 mph. The roads were crap and travelling faster than that was dangerous. At those speeds, aerodynamics don't matter at all.
It is only when we started routinely travelling at 45 or greater that they began to take aerodynamics into account for street vehicles.
It didn't take that long (Score:2)
This is just silly. (Score:2, Informative)
Chrysler started mass production of a streamlined car in 1934, the Airflow. People didn't buy it. Tatra, in Czechoslovakia, also sold a streamlined car in 1934. Lincoln produced one also in the 30's and Pontiac came out with one in the 40's. Bugatti ran a streamlined racing car in 1923, the Type 32. The Jaguar XK-120 went into production in 1948 and there were many pre-war low production sports and show cars that were streamlined. All of these cars had curved aerodynamic bodies that expressed our understand
Those Curves Come With Drawbacks (Score:2)
I have a highly streamlined car, and there are drawbacks to it. The gentle slope of the front and the kammback on the rear make it impossible to see just where the car ends, which makes parking problematical.
The entire car is low to the ground to reduce air going under it and causing drag. This make it tend to scrape on anything bigger than a tennis ball, and puts the drivers seat uncomfortably low.
The roof line has been cleaned up, which is nice, until you go to mount a roof rack and there's nothing to c
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You're the rare person here to observe that streamlined cars are low to the ground in a way that many well-heeled customers might not appreciate from an ergonomic perspective.
[*] By ergonomic perspective, I mean that your mink stole might drag on the ground on your way in or out, or you might break one of those well-
Pre-interstate, large engines, etc (Score:5, Insightful)
In the US, the interstate system was not started until 1956. It wasn't until the mid 70s that the first state had completed all of their interstate construction. So throughout the 50s, 60s, and into the 70s, the interstate system was a hodgepodge of completed sections, with two way highways still being the majority of roadways traversed for long distance travel.
So.... cars really couldn't cruise at the speeds we enjoy today during the exact time range questioned by the story (50s, 60s, 70s). Since aerodynamic efficiency gains are a direct product of the operating speed of a vehicle, that efficiency simply wasn't realized at that time.
Additionally, that was also the era of the muscle cars and V8 engine. Even non-"sporty" cars would have large, powerful engines. That was also a byproduct of the roadway system. With two way roadways, you have to pass cars quickly and get back into your lane whenever an opportunity allows. The more powerful your car, the faster (and arguably safer) you can overtake vehicles and get back into your lane of travel.
These two lane roadways also traveled through every town along the way, and climbed over every mountain and hill (as opposed the them being graded down or tunnels). Again, the ability to accelerate quickly from stops and ability to climb hills made large engines desirable.
Those large engines were gas guzzlers - especially when you consider they were carbureted, used primitive ignition (distributor) and had no simulations or other analytics performed during engine design to optimize them.
You combine all those things together - roads in which you could not cruise at speeds over 55 for long stretches, very large extremely inefficient engines, and repeated accelerations - and the impact of aerodynamic design in real-world savings was so small that cosmetics and style were easily greater factors than aerodynamic efficiency.
Begging the question, incorrectly. (Score:3)
Define aerodynamically shaped. Are you going for purely looks, or are you actually concerned about the aerodynamics affecting your fuel consumption. If you're talking about the latter it's worth reading up on Coefficient of drag. It's also worth reading up on why cars like the Ferrari F50 (a marvel of aerodynamic design) have the same co-efficient of drag as the new fat and ugly VW Beetle and worse than the current Cadillac Escalade.
Engines need cooling, (in the days of the Porsche 64 this was even more important). Performance cars need drag to stick to the ground. And the cars which are actually the most aerodynamic (in the sense of least air resistance, not in the sense of "wow cool sports car man!") are modern family sedans and hybrids, e.g. BMW 320d, the bulky Tesla Model X, or the very ordinary looking Mazda 3 sedan.
In terms of drag, the 1970s family sedans like the Peugeot 407 had the same Cd as a current model Porsche Boxster.
Computing power (Score:5, Interesting)
The Navier Stokes equations are computationally demanding, and many of the approximating methods were specific to aircraft.
A Look at the History of Computational Fluid Dynamics [shortsleev...ieclub.com]
says that GM and Ford only adopted the technology in 1995.
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Not at all. Cd hasn't changed appreciably over the years and there were some very aerodynamic cars in the past which didn't need fancy computers. What is topping the chart now in drag is cars that don't need front grills or air intakes for their intercoolers.
Style preempts function. (Score:2)
Limitations of production design (Score:2)
The automotive industry typically is very conservative with new new technologies. CNC machines were first designed in the 50s. They didn't really become common until the late 70s. CAD was extremely limited in the 60s. It gradually got better. But computer memory was extremely limited.
looks can be deceiving ... (Score:2)
A Bigger Question: Why Are We Regressing (Score:2)
It's him again - the polygons 'tard (Score:2)
Probably for the same reason pixels aren't banana shaped.
What!? (Score:3)
Huh? Cars have been aerodynamically shaped in the past, less so nowadays generally with more pickup trucks (horrible drag coefficients), SUVs/minivans in the US in particular.
Safety standards now also mandate aspects that restrict the ability to have some aero design. But also, gas has been cheap, people don't care about power to weight ratios or CD--it can be hard to actually get that info on cars compared to less useful info.
Add that rarely do cars travel fast enough for drag to be a huge issue, most spend most of their time in traffic conditions making it irrelevant. Heck it was only recently the national US speed limit was raised from 55!
Sports Cars (Score:2)
It's easy to make a two seater sports car, or roadster, aerodynamic and pleasing to look at simultaneously. It's quite a bit different to build a four person family car with enough back seat space for a rear facing car seat, AND trunk space for groceries or road trips in the trunk.
flawed premise (Score:2)
Gas was more expensive when cars were boxier not cheaper.
Gas has trended cheaper and cheaper for the last 100 years.
Cars are like those who drive 'em (Score:2)
They were slim, now they're fat. I use the term "bubble car" to describe the modern look.
Because gasoline was DIRT CHEAP and PLENTIFUL (Score:2)
Chrysler Airflow and Airstream (Score:2)
It's interesting to note that the Chrysler Airflow (1934) was intended to be aerodynamic, but didn't sell well, which led to the Chrysler Airstream (1935) which looks a bit streamlined and modern but actually isn't aerodynamically designed.
Because it was and is good enough in most cases (Score:2)
Because someone has to build them (Score:2)
Curves are hard to make precisely, and the cost-effective manufacturing techniques at the price point for cars made it simpler to build boxes.
Even today, the manufacturing tolerances for aircraft are multiple orders of magnitude tougher than that for cars.
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Even today, the manufacturing tolerances for aircraft are multiple orders of magnitude tougher than that for cars.
I'm not sure I buy that. Got anything I can read up on?
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Nope, but my firm sells a product (release liner) used in carbon-fiber sheeting manufacture.
Failure tolerance for our products going to the suppliers selling to the automotive industry is 3- or 4-sigma. Tolerance for our product going into the construction of the 787 is 6 sigma (or higher, depending on how you want to define it).
Even setting that aside, its pretty obvious that aircraft have multiple layers of control systems and backups in many systems for which cars only have one. Cars don't carry anywhe
Cabin space (Score:2)
I think the questioner has made a common mistake (Score:2)
Aerodynamics != Aerodynamics. The question compares aircraft to cars, when one is designed to stay up, while the other should be designed to stay down. At first thought you might even think a properly designed car should look like an upside down airplane, but in reality cars have to spend a lot of effort fighting ground effect flows, and the aerodynamic environment is nothing like flight.
The Porsche in the article probably would have really bad lift tendencies at speed, it was not a fast car, and round bu
Evolution of previous archetype (Score:2)
Early cars resembled horse-drawn carriages with an engine in place of the horses. The same boxy form which resisting going airborne when jostled over bumpy roads held true until roads improved and drivers could be reasonably certain that they would be driving asphalt-to-asphalt over the course of their journeys. At that point, the form was established, and could be modified to be more efficient.
At the end of the day... (Score:2)
Your average car purchaser is asking himself the question “Will this car get me laid”.
There is nothing aerodynamic, and certainly not fuel efficient, about the SUV in the very large class that belong to cars like the Cadillac Escalade, Lexus LX 570, Lincoln Navigator, etc. most of these decisions are completely vanity driven. Some of the designs in the 50s were based on concepts stemming from the ‘Atomic Age’. Diners, campers, etc all had that flash gordon look. Take the the 1957 Fo
Because gas was cheap ... (Score:2)
... and the mother of invention had just given birth to the automobile.
yw
Why is submitter ignorant about topic? (Score:2)
I googled "aerodynamic car history" (no quotes) and came up with this link:
An Illustrated History of Automotive Aerodynamics" [thetruthaboutcars.com]
The 1930s was a hot-bed of efforts to produce aerodynamic cars - the war at the end of the decade was likely a bit of a distraction - but efforts began as early as 1899:
Racers, particularly those chasing the coveted Land Speed Record (LSR), were generally the first to employ aerodynamic aids. The La Jamais Contente (The Never Satisfied) was the first automobile to break the 100kmh (62 mph) record, in 1899.
This is a multiple variable problem (Score:2)
Early cars were designed with paper drafting and clay mockups. The time it would take to redraft or craft an outshell could be prohibitively expensive and rework for design errors even more so. The best example of this is the mid fifties ford that missed
Fuel was dirt cheap (Score:2)
In the USA, maybe (Score:2)
But then, they were in the grip of land-barge-itis or something until the 1970s oil crisis
1955 [wikipedia.org]
1958 [wikipedia.org]
1961 [wikipedia.org]
1962 [wikipedia.org]
The engines were too big. (Score:4, Interesting)
Engines didn't get small enough until the 1990s. Since the engine of most mainstream vehicles is in the front, it dictates the minimum height of the passenger compartment, since the driver needs to see well above the engine.
Larger engines mean higher and larger passenger compartments. This means less flexibility for the overall shape of the vehicle. This means the shape can't be dictated by aerodynamic concerns as much as with smaller engines.
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The suspension type dictates the height.
And the road surface dictates suspension. How many roads were paved in the 1930's? You try taking driving in some of the poorer countries on the planet to find out. You won't do well with your 5" ground clearance city sedan and big leaf springs can take a beating from potholes, but nowadays you'll find those mainly on tractors and trucks (and the odd 4x4).
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You are inventing bullshit
There's definitely a lot of baseless speculation occurring.
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If you're only considering small block vs big block you're missing a huge part of their point.
You're missing his point.
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Re: Why do environmentalists still drive and fly? (Score:2, Insightful)
It's about forcing change on everyone, not changing yourself.
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because road conditions
Porsche was developed in Germany. The land of the autobahn. Which Eisenhower saw and decided that we needed this too.
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Re: Aerodynamically Shaped? (Score:2)
Auto is about automation, automatons/robotics and such. Things that can accomplish tasks on their own. Autodynamics would be a study on Transformers robots?
Aeroplanes are pointy at the back, not the front (Score:3)
Modern cars with pointy fronts and blunt backs are terrible aerodynamically. It is just fashion.
Look at an aeroplane or its wing. They key is to minimize wake turbulance, which means a pointy back.
The fashion for pointy fronts and flat windscreens makes cars hot. Much hotter than in the older days. This is only possible because they now all have air conditioning. Which is now needed on even moderately warm days. Making a car into a green house costs lots of energy to run those air conditioners.
Non-ene
Re: Aeroplanes are pointy at the back, not the fro (Score:2)
O
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"Water naturally morphs into this shape when falling."
Ehm, no.
https://www.google.com/search?... [google.com]
Re: Aeroplanes are pointy at the back, not the fr (Score:2)
I thought it made sense that water would take the most aerodynamic shape when falling, I guess that it does indeed make more sense that it would not. I wil need to look up more about the physics of interactions between water and air at some point,...
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"... and blunt backs are terrible aerodynamically."
Not as bad as you'd think. If you truncate the ideal pointy back, you get a Kamm back, which is still pretty good. What would be much worse is smooth, blunt back (like an airplane flying backwards). The key for a good Kamm back is that the edge of the truncation is sharp, so the airflow will separate from the surface. The mini spoilers that many cars have nowadays (usually above the rear window) are for that purpose, so that there is more design freedom in
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