1000-mph Car Planned

Smivs notes a BBC report on a British team planning a 1000-mph record-breaking car. The previous land-speed record broke the sound barrier. The proposed vehicle will get from 0 to 1,050 mph in 40 seconds. "RAF pilot Andy Green made history in 1997 when he drove the Thrust SSC jet-powered vehicle at 763 mph (1,228 km/h). Now he intends to get behind the wheel of a car that is capable of reaching 1,000 mph (1,610 km/h). Known as Bloodhound, the new car will be powered by a rocket bolted to a Typhoon-Eurofighter jet engine. The team-members have been working on the concept for the past 18 months and expect to be ready to make their new record attempt in 2011."

Comments

1000 mph speed, 100 gallons per mile efficiency

[Drakkenmensch]

I can't help it but giggle when these speed-record setting land vehicules are referred to as "cars" when they're basically rockets with wheels and a seat.

I've got a better idea

[elrous0]

How about a 1000 mpg car?

Re:I've got a better idea

[Ice Tiger]

How many land speed record attempts do you know that were done by vehicles intended for commercial production and sale?

Part of this project is to inspire the younger generation whilst at school that engineering and science isn't dull and boring and something worth getting fired up about. The UK has a shortage of home grown talent when it comes to engineering and this is helping change that for the future.

Re:I've got a better idea

[Wrath0fb0b]

Some simple calculations will show you that 1000 mpg (for g as in gallon of gasoline) is physically impossible.

(1) Energy content of gasoline --- 36.6 kWh/US gallon. Let's assume that your engine works at the absolute thermodynamic limit (40%) for a combustion engine so you get 16 KWH of work out of it.
(2) The power to move your vehicle through air is P = (1/2)(density)(projected area)(drag coeff)(velocity^3)
(4) At sea level, 25C, 60 MPH, A = (1 m)^2, CD = .1, you have to expend P = 1.25 KW to continue moving.
(5) In one hour, therefore, you have consumed 1.25 KWH ~ (1/12) gal. You have also moved 60 miles, giving you 60*12= 720 mpg.

So, even under the most generous conditions, you cannot possibly do better that 700 mpg. Of course, we have neglected rolling friction of the tires and assumed that your regenerative braking system is so good that you expend no net energy starting and stopping. 720 mpg is just the energy required to move the air out of your way as you cruise to work.

At first, I was going to mod you OT and move on, but I felt like there was something important to be said here -- efficiency is not like performance. In performance, one can always throw more energy at the problem (he's using a jet engine FFS, new sports cars are always breaking HP limits) but when going for efficiency, you are going to see diminishing returns. 100 mpg is doable, 200 mpg is doable with severe sacrifices (mainly in the comfort/cargo dept). Past that, I feel like the laws of physics are not going to be particularly kind.

Re:I've got a better idea

[Miseph]

Of course, one can always ignore your calculations by doing things differently than how you expect.

For example, what is the thermodynamic limit of fuel cells? What are the thermodynamic limits of every other alternative fuel or alternative engine type? What if we use more highly refined fuel that carries more energy per unit? What if you do not travel at 60 mph in order to lower wind resistance? Speaking of wind resistance, what if you were to travel through specially designed low air pressure conduits to make air resistance nearly 0? We can change all sorts of things about the situation to make your math, while good, completely irrelevant to the scenario.

The real question...

[xcog]

How many MPG will it get? And where can I dock my iPod?

Re:The real question...

[innit]

Yeah, if Britain was 11 miles long.

Re:The real question...

[sqldr]

Having cycled from Lands End to John o' Groats twice, I can tell you that the shortest route from the two most distant points on great britain are 857 miles apart. The route we took was 1050. Based on this, by the time he hits 1050 mph, he would barely be out of cornwall. Then again, it's quite mountainous around there, so he would probably be quite high in the air by that point.

falling forwards

[dnwq]

(1050/40) (mph / second) = 1.19661658 g. Neat. Accelerating just above the rate one falls. No excessive gee forces to worry about, at least.

Re:falling forwards

[SirLoadALot]

You are assuming constant linear acceleration. I think it is safe to say that the acceleration when the rocket motor is turned on will be somewhat more dramatic than that. Even if you use your figure, bear in mind that gravity will still be there, and the combined force will be sqrt(1.19g + 1g) = 1.55g, so the pilot would feel 55% heavier than normal.

Re:Car? Or rocket on wheels?

[Anonymous Coward]

While I agree with your not-a-car sentiment, I think it is still a valid pursuit to attempt to break prior records. Generally, progress is measured by either surpassing previous measurements of progress, or by managing something entirely new. I think this qualifies for the former.

Re:thats a big splat

[drerwk]

the last person i heard of strapping a rocket to a car to see how fast they could go ended up driving into a mountain because he couldnt stop

The intention was not to stop, but an actual test of the Overthruster.

and this was in the salt flats of utah (at least thats where he started, clearly it wasnt so flat where he ended up)

Certainly the 8th dimension would not be described as flat!

Sponsors?

[speroni]

Is this an ACME funded project?

ACME

MPG is an obsolete measurement

[Shivetya]

I know it is not currently but it will be one day.

I like achievements like these. I know it costs a lot of money but my hat off to the engineers who can come up with these machines let alone the driver who dares to do it. Too many people want to sit on their couch and bitch secure in the safe little world and never get out to live life.

I know many will scream "whats the point". Well the point is that no one has done it, people claim it cannot be done, and throw in the challenge of trying. It gives kids something to dream about, perhaps sparking some enthusiasm for different careers.

Besides we might just learn something

Re:MPG is an obsolete measurement

[Ice Tiger]

Using a jet engine off the shelf isn't the hard part, btw the rocket is a HTP hyrbid rocket that is developed for this project.

The real brain cruncher is how you design a vehicle that can survive an environment where supersonic shock waves are being reflected off of a desert floor back onto the body of the craft and so on. Remember the wheels are travelling on the ground at mach 1.4, if they were uncovered the top of the wheel would be travelling at mach 2.8 with regards to the local airflow. That's up there with the SR71 in terms of velocity.

Hardly off the shelf.

Re:MPG is an obsolete measurement

[spideysense]

Yeah, and I bet the Dodge Neon you strap those rockets to hold up real good at 1000mph. It takes some engineering to withstand those kind of forces without blowing the car and the driver into tiny pieces. But please give me a call when you try your little experiment - I'd love to watch.

Re:MPG is an obsolete measurement

[ATMD]

I expect my lecturer would disagree with you on that point. I'm an undergraduate at Swansea University, where a lot of the work (such as the aerodynamics) is being done. The computational fluid dynamics code that's being used to allow this thing to go 1000mph was developed here, powers aerospace firms like Airbus, BAE Systems and Rolls Royce, and has been decades in the making.

Which means that you sir, are trolling.

Re:MPG is an obsolete measurement

[NoNeeeed]

As JFK once put it very succinctly...

"We choose to go to the moon, and do the other things, not because they are easy, but because they are hard"

If all we ever do is the easy stuff, nothing ever changes.

And for all the people saying this is easy, why don't you give it a try then? It isn't just the money, this stuff takes serious engineering and real talent on the part of the driver/pilot.

What amazing stuff have you done in your life?

Re:MPG is an obsolete measurement

[Sockatume]

To misremember the words of some journalist covering the Thrust SSC: while getting to the sound barrier in a vehicle with wheels is easy, doing so without inadvertently turning your car into a new kind of aircraft or tunneling machine is rather more difficult.

Re:MPG is an obsolete measurement

[hey!]

Asking the point of engineering feats like this is like asking the point of sex being enjoyable. The point of sex being enjoyable is to encourage procreation. The point of engineering being enjoyable is to encourage creativity.

Of course, engineers like to see their creations at work, doing useful things, just like chefs love to see people eating. But speaking as an engineer who grew up in a restauranting family, you've got to be a little bit insane to go into either business. Nobody would become a chef unless they had a bizarre compulsion to cook. My brother went into that business, and you literally can't keep him away from the stove or the grill if there is cooking going on. The only reason he can sit still in a restaurant, I think, is professional interest in other aspects of the diner's experience, but even then he can't resist the temptation to host the meal, to buy drinks, to make suggestions for what to select from the menu. Some of his buddies have actually put full restaurant kitchens in their garages and spend their time off cooking.

When I visit my relatives, on the other hand, I find myself fixing their computer problems. I can't not fix their problems, even though I hate dealing with those kinds of messes. If cars were as easy to work on from general knowledge as they were forty years ago, I'd probably be fixing their cars too. I'm just addicted to the satisfaction of getting everything sorted out.

Re:MPG is an obsolete measurement

[hierophanta]

it become obsolete when we stop using gasoline -- gallon of what? in the future we might be seeing measurements like miles per kilowatt

Re:MPG is an obsolete measurement

[Shotgun]

Stop insulting trolls. He's just a clueless idiot.

BTW, most people don't realize that their tires are speed rated. Tires are just rubber balloons, after all. Just ones with really thick walls. They will deform and even come apart if pulled hard enough. The faster a car goes, the more pull on the tire's tread and sidewall. Once the pull starts, it will most likely deform to an out of balance shape. In this case that out of balance will translate to a vibration, which translates to a bump, which translates to a lot of pieces to pick up off the desert floor.

A post above gave the figure of 173g for a 1m wheel travelling at 1000mph. That 1m wheel will be spinning at 8542 RPM. A slight imbalance at that rotational rate? Even the engineering of the tire will need novel ideas for strengthening the sidewall and lightening the tread to keep it balanced.

Re:MPG is an obsolete measurement

[Shotgun]

Engineers who are paid for what they are doing are encouraged to use established solutions. That's why engineers go home and work on their own projects. Then they get to do something different, just for the sake of doing something differently.

Re:MPG is an obsolete measurement

[Retric]

Your at 4x the correct g. The rate of rotation is based off of the speed of the car relative to the speed of the ground. The top of the tire is moving at twice the speed of the car relative to the ground but the bottom is not moving relative to the ground. However, it's all 1x the speed of the car relative the center of the tire. Which is the frame of reference you need to calculate the centripetal force. PS: It's also a good idea to note only the outside edge of the tire is under that much g loading as to move to the center of the tire the g forces drop to zero. (It's still an insane speed to rotate a tire.)

Re:MPG is an obsolete measurement

[Anonymous Coward]

Reasonable men adapt to the world around them; unreasonable men make the world adapt to them. The world is changed by unreasonable men.

-- Edwin Louis Cole

Re:MPG is an obsolete measurement

[2names]

Besides we might just learn something

Yes, we might just learn if Fruit of the Looms can withstand the force of a 1000 MPH "Oh SHIT!" moment.

Re:MPG is an obsolete measurement

[kazamx]

I sometimes get the feeling the readership of Slashdot has aged over the last few years. The wonder excitement and enjoyment of doing something seems to be on the way out and cost/benefit productivity gains and other boring crap seem to be what people worry about. There was never a reason to go to the moon. There was never a reason to climb Everest. There was never a good reason to go to the North or South Poles. There was never good reason to do many of the cool things we did, that is until we did them.

Re:MPG is an obsolete measurement

[Gilmoure]

Maybe someone could figure out how to use the force of the air rushing past the car to help support it or even totally suspend it so one wouldn't have to use wheels at all. That would be cool!

Re:MPG is an obsolete measurement

[Chris Daniel]

measurements like miles per kilowatt

Kilowatt-hour is what you want here. The watt is a _rate_ of energy consumption (power), not a lump of energy. Kilowatt-hour is the equivalent of one kilowatt consumed over the course of one hour: 1 kWh = (1000 joules / second) * 3600 seconds = 36000 joules

Jeremy Clarkson:

[Anonymous Coward]

Hamster! You want to try it out ?

Re:When does it stop being a car?

[YrWrstNtmr]

Then they should just run a Eurofighter on a runway trying not to take off... Just as much a "car" as this thing.

Fighter jet landing gear and tires are not built for 1,000mph. Maybe 300-350 absolute max. Rebuild it to do 1,000mph, and you'll end up with something that looks quite a lot like this thing does.
One similar speed record 'car' is literally an F-104 body, sans wings.

the point

[confused one]

Whatsthepoint

"Candy doesn't have to have a point. That's why it's candy" -- Charlie Bucket, Charlie and the Chocolate Factory

If you can't see the analogy... We may not be able to save you.

Re:So?

[Just Some Guy]

lol something going that fast cant. at those speeds it litterly is flying. the gforces litterly pull it off the ground and its riding on them.

I feel dumber for having read that.