http://www.runyourcarwithwater.com/top_logo.jpg

I thought it was an article on a 6 cycle engine for a moment there, but no its stupid. The energy wasted in electrolysis will not provide a return when you burn the hydrogen and oxygen.

Ruin you car with water. Run your bath with water.

Give lots of gas to your car. Fight wars for your car. (just kidding)

Demand a plug-in electric car, and from most utitily companies it's like getting your "gas" for 20cents/gal. I'm converting a 1968 Beetle into a (hopefully) 50-mile range, 50-mph "lightnin' Bug" for about $5k. The conversion should pay for itself in less than 5kmiles.

Demand a plug-in electric car, and from most utitily companies it's like getting your "gas" for 20cents/gal. I'm converting a 1968 Beetle into a (hopefully) 50-mile range, 50-mph "lightnin' Bug" for about $5k. The conversion should pay for itself in less than 5kmiles.
50 miles isn't very far, but I guess it would be good for hopin' around town. What kind of performance do you expect?

50 miles isn't very far, but I guess it would be good for hopin' around town. What kind of performance do you expect?

50 miles covers 70% of commuters. I expect the performance of any regular car... that can spin around 360 while in place, that can drive sideways, that can start from a stand still with fuel torque, that requires less maintenance and that will become a necessity when gas gets way beyond $4 a gallon (a likely event by 2010 when the first commercial pre-built PHEVs come on line)

I thought it was an article on a 6 cycle engine for a moment there, but no its stupid. The energy wasted in electrolysis will not provide a return when you burn the hydrogen and oxygen.
Yeah, this is a worthless gimmick. Electrolysis is not an adiabatic process and as such it is bound to be energy negative since all the laws of thermodynamics apply. It takes more electrical energy to create a fuel mass than can be recovered from the same mass in combustion, even given a 100% recovery efficiency. An ICE is only about 30% efficient in converting thermal to kinetic energy at the crank, and loses the other thirds to exhaust heat and heat in the cooling system. And where to they propose getting energy for electrolysis? From the vehicle's electrical system; a system that can support maybe an 800 watt parasitic load while the vehicle is in motion. The amount of electricity available won't be enough to generate gas quantities in any meaningful amount, and the vehicle's powertrain will make shitty use of what little additional fuel it ever sees. Equipping the vehicle for a pressurized fuel system, and then dyno tuning it to keep the right mixture throughout the power band and at different throttle positions, will cost thousands more than the electrolytic cell does.

This strain of gimmicky bullshit will probably get worse before it gets better. As long as being all green and eco-friendly is the cause du jour, there will be legions of greedy charlatans out there trying to make a quick buck off some rich douchebag's guilty conscience.

Now a 6 cycle/stoke engine the runs on water there is a idea. After the exhaust stroke you have a water inject and steam exhaust stroke, this cools the engine and uses the heat to do pv work, efficiency of the engine increase ~40% (at the cost of having to fuel up in both gasoline/diesel and distilled water) fortunately water is cheaper then fuel.

I have seen that, ElectricFetus! It's an amazing invention.

"What kind of performance do you expect?"

I'm on a low budget for this first trial, so it's not going to be spritely. I'm using cheaper, but much heavier lead-acid batteries. I'm just in the stage of taking the car apart for conversion, I've got 3/4 of the batteries now, still learning / haven't decided about the motor (pdf link) (http://www.solren.com/downloads/ac22ay.pdf) and inverter/controller yet (http://www.solren.com/downloads/dmoc445.pdf). I'm hoping for performance at least comparable to what is claimed in this DC example (http://www.electroauto.com/gallery/bug-1.shtml).

Now a 6 cycle/stoke engine the runs on water there is a idea. After the exhaust stroke you have a water inject and steam exhaust stroke, this cools the engine and uses the heat to do pv work, efficiency of the engine increase ~40% (at the cost of having to fuel up in both gasoline/diesel and distilled water) fortunately water is cheaper then fuel.
Do you have any additional information on this? It doesn't seem like a very good idea. You'd be burning 20% less fuel per revolution, so your specific output is going to be less no matter what, and peak torque is what matters in an application like a vehicle where part throttle cruising followed by short bursts of WOT acceleration are what is needed. Even for constant RPM applications, like running a generator, there is no such thing as a free lunch. Water flashing to steam is going to have a very hard time generating any amount of pressure inside the cylinder that comes close to what a mass of fuel can when it combusts, and those lost cycles will be further exacerbated by frictional losses that are identical to an Otto (four stroke) engine.

On the plus side, combustion chamber temps will be lowered by the phase change, so you can run more boost out of a turbo and advance ignition timing somewhat, with a lower octane fuel. Also, the cylinder will be getting steam cleaned all the time to keep it free of deposits. It still doesn't sound like more than a novelty to me, but I would be very curious to see some numbers that show otherwise.

Do you have any additional information on this? It doesn't seem like a very good idea. You'd be burning 20% less fuel per revolution, so your specific output is going to be less no matter what, and peak torque is what matters in an application like a vehicle where part throttle cruising followed by short bursts of WOT acceleration are what is needed. Even for constant RPM applications, like running a generator, there is no such thing as a free lunch. Water flashing to steam is going to have a very hard time generating any amount of pressure inside the cylinder that comes close to what a mass of fuel can when it combusts, and those lost cycles will be further exacerbated by frictional losses that are identical to an Otto (four stroke) engine.

On the plus side, combustion chamber temps will be lowered by the phase change, so you can run more boost out of a turbo and advance ignition timing somewhat, with a lower octane fuel. Also, the cylinder will be getting steam cleaned all the time to keep it free of deposits. It still doesn't sound like more than a novelty to me, but I would be very curious to see some numbers that show otherwise.

google: 6 stroke engine (Crower_six_stroke)
-claims torque increase because there is now 2 power strokes per cycle of six (1/3) over 1 stroke per cycle of 4 (1/4).
-claims steam pressure provides ample power.

I would figure it would work great for fresh water crafts (as long as the water is filtered.

Interesting. Given that Bruce Crower is behind it (his shop built the valvetrain in the car that I race) I have little doubt that there are merits to these claims. It appears that some of the 1/3 of waste heat that normally is dissipated by the cooling system is being recouped and transmuted into KE at the crank using the water phase change. Which means that these engines shouldn't need much of a cooling system, if any. I would think they would work great in constant-throttle/RPM applications like diesel-electric locomotives and generators, but still have my doubts as to whether or not cars would benefit from a system that clearly reaches peak efficiency once it hits thermal equilibrium. It doesn't look like he's put one of his prototypes on a dyno yet, though, so the jury's out on what gains there are to be had. In any case, it is a neat concept.

The 6 cycle engine still throws most (certainly >50%) of the fuel energy away in the hot exhaust. Much better would be to use that heat by a fine water droplet mist injected as the piston is moving down on the power stroke to sustain higher pressure on the piston as the liquid drops become steam. I.e. throw away a much colder exhaust. I accidently did and confirmed this once many years ago
in some very careful fuel efficiency experiments I made one summer. All of my data made no sense until I realized that the water droplets in the air were not under my control and very important for improved fuel efficiency.

I made a standard 100+ mile run home every week end, starting with 100 hour used "new" spark plugs from my oil company summer job's dynamometer lab; filled the gas tank to a scratch line made inside the filler tube while parked in same position at same "start and finish" gas station pumps etc. -I.e. I was very careful. For more details. See http://sciforums.com/showpost.php?p=1713574&postcount=117 My best efficiency was on a foggy eve, with lights and radio on (as an extra computable load).

I think a minor change to the carburetion of standard engine to add water mist injection would be much better than a 6 stroke cycle, but probably there are undesired long term side effects, especially if non-distilled H2O is used as US Air Force only did water injection in emergencies when pilot was desperate for a brief step up in power.

When an engine builder refers to "thermal equilibrium" they're talking about the point where the engine is producing as much waste heat as its exhaust and cooling system is dissipating, so the exhaust gas and coolant temps are constant. This is as opposed to most driving situations, where rapid throttle position changes and the thermal transients they create keep the engine in a constant state of hysteresis, never mind that the thermostat produces hysteresis all else being constant. It is one of those cases where convention defies the correct use of the term.

The thread you're looking for was here: http://sciforums.com/showthread.php?t=75963&page=7

When an engine builder refers to "thermal equilibrium" they're talking about the point where the engine is producing as much waste heat as its exhaust and cooling system is dissipating, so the exhaust gas and coolant temps are constant....Ok - In most areas however, one avoids using "equilibrium" When there are large thermal gradients in good conductors like metals and corresponding huge heat fluxes. Then, as I said "steady state (conditions)" is normally used, but I can understand why people evaluating ICEs might speak as you report. Two more extreme examples of wide spread, but technically incorrect terminology are:

Astronomer's use of "metals" to refer mainly to Oxygen, Nitrogen, Carbon and other common low atomic number elements.

Everyone, but me, use "neural networks" to refer to multi-layer computers with "connections" between the layers. Thus, I call them "connections computer" or "connection machines." They "lean" from a "sample set" of problems, containing the correct answers. After it is well practiced on the sample set, it can solve similar problems very rapidly (compared to a programmed computer making a series of sequential steps).* During the "learning process" the connection machine adjusts the strength of the connections between the various layers (usually 3, "input", "output" and "internal layer") without any help from a human.
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*Modern programmed computers execute steps so rapidly that speed is not the main advantage of a connection machine. That is the fact that you do not need to even need to understand the problem well enough to be able to program a sequential step machine to solve the problem. The connection machine will learn how to solve the problem without any aid from you, except allowing it to practice on the sample set.)

You obviously understand well that the ICE field's use of "thermal equilibrium" is not an equilibrium state. And also I am sure, understand that only a very small fraction (almost negligible) of the waste heat the car's "radiator" transfer to the air is by radiation.

I often try to correct these gross terminology errors when I can, as not everyone is as well informed as you.
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Thanks for locating my old thread. I have found in it my post giving more details about my careful fuel efficiency experiments and modified my earlier post to give direct link to that description. (Also removed my comments on your use of "thermal equilibrium" as in the context of that field it is used as you did.)
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Do you agree with me that water mist injection during the piston's "power stroke" of a 4 cycle ICE is very likely to be superior to the 6 cycle ICE with separate steam and fuel power strokes? (because less thermal energy would be discared.)

Also, do you think my guess, based on fact it was only done in WWII planes when pilot was in big trouble, that there is some long-term bad side effect to water being injected into a hot piston chamber is correct?. What might it be?

Sometimes my job keeps me away from this place for a few days...

You obviously understand well that the ICE field's use of "thermal equilibrium" is not an equilibrium state. And also I am sure, understand that only a very small fraction (almost negligible) of the waste heat the car's "radiator" transfer to the air is by radiation.
Yeah, barely anything. Last racing season, I tried coating the intercooler of the car I take to the track in a ceramic material that was flat black color. I was hoping that it would increase the radiative mode of heat loss, as a black body source radiates heat more effectively than a shiny object, and the intercooler was previously bare aluminum, and quite shiny. The ceramic compound itself is designed for this application and is a good conductor of heat rather than an insulator. It ended up making a slight difference in the temperature of my intake air, but only when the car was idling or traveling very slowly so little to no air was cooling the IC by convection. The times it helped most was during cooldown sessions as I sat in the paddock, right after I had run a few laps. Was it worth the $170 I spent to have it coated? I don't think so, but it satisfied my curiousity.

Do you agree with me that water mist injection during the piston's "power stroke" of a 4 cycle ICE is very likely to be superior to the 6 cycle ICE with separate steam and fuel power strokes? (because less thermal energy would be discared.)
I do agree. The 6 stroke method might produce a higher brake specific fuel consumption (http://en.wikipedia.org/wiki/Brake_specific_fuel_consumption) and be more efficient in certain conditions, but for a passenger car, I still have a hard time believing the vaporization could produce as much impulse energy as combustion does. I haven't seen a white paper on Crower's design though, so I could be overlooking something.

Also, do you think my guess, based on fact it was only done in WWII planes when pilot was in big trouble, that there is some long-term bad side effect to water being injected into a hot piston chamber is correct?. What might it be?
There really isn't any downside to water/meth injection if it is tuned correctly, because it just provides a safe condition where the ignition can be advanced or boost can be run before you run into detonation (knock). If the bottom end - pistons/wrist pins/conrods/crank throws/main bearings - aren't up for the increased torque that comes from all that, then there would be problems, but they wouldn't really be a direct fault of the methanol, just an overzealous tuner.

I could see stress fractures from uneven heating/cooling of the head, cylinder sleeve, or piston top resulting from an injector solenoid being stuck wide open, maybe, but at that point the engine would be bogging and misfiring anyway so it would obviously have something wrong with it.

...I tried coating the intercooler of the car I take to the track in a ceramic material that was flat black color. I was hoping that it would increase the radiative mode of heat loss,...I doubt if I have ever seen an "intercooler" and am not sure even what they do, but recommend wrapping the IC with a simple wet rag or something like that (dipping into a 'water well" if race is long) to get some evaporative cooling. If not too effective, and legal, some dry ice would work well and not wet anything*

I hate to mention it, but it will work better if you scrape off that $170 insulating film you applied. :bawl:

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*Then perhaps no need to scrap off the black paint. In fact, you may need to play around a little with some more insulation film and a thermometer to find how much insulation between slab of dry ice (externally well insulated from the hot air in motor region) and IC produces the optimum IC function.

Obligatory link to Wiki article on intercooling: http://en.wikipedia.org/wiki/Intercooler

The intercooler (sometimes called an aftercooler) is a heat exchanger that cools the intake charge air in a boosted engine, be it turbocharged or supercharged. The IC is placed in the intake air path so the air is ducted through it after being compressed by the turbo or SC, thus gaining a significant amount of heat. It usually sits in the front air intake area, ahead of the radiator. The IC looks like a radiator but rather than a liquid to air heat exchanger, they are usually air to air. Liquid to air intercoolers are only used when space is very tight and the high specific heat of water is needed to make up for the reduction in fin surface area. The Evo shown here has an air to air intercooler in the lower intake aperture, as well as one sitting next to it:

http://www.nisei-evo.com/products/intercooler_photo1.jpg

When the turbo or SC compresses the intake air, the air heats up. Some of this is due to compression itself (see also: ideal gas law (http://en.wikipedia.org/wiki/Ideal_gas_law)) but most of it is due to the inefficiencies of the type of compressor being used.

Some superchargers, like the Roots blower (http://www.superchargersonline.com/content.asp?ID=76), are not very efficient at all. They generate lots of heat, mostly due to the turbulent nature of their dischage. As the air molecules come swirling out of the blower outlet, they rub into each other, and that friction produces heat. Also, the roots tends to recirculate air through the housing once pressure on the outlet side exceeds a certain amount (on most Eaton blowers used nowadays that amount is around 11 PSI) and that has an additional heating effect.

Other compressors, like the Lysholm (twin screw) (http://www.superchargersonline.com/content.asp?id=20) are more efficient because they compress the air internally and do not allow backflow regardless of outlet pressure. Due to their external dimensional similarities to Roots blowers, it is popular to swap a Lysholm in place of a Roots when you want to increase boost levels beyond what the stock system was designed for and also get better efficiency.

Most efficient is the centrifugal compressor (http://www.superchargersonline.com/content.asp?id=21). While these can be found in belt driven forms as superchargers, centrifugal compressors are used exclusively in turbochargers (http://en.wikipedia.org/wiki/Turbocharger). In that application they are mounted on a common shaft of a turbine that is placed in the exhaust gas stream, and driven by exhaust energy. Because turbos are driven by the pressure and waste heat of exhaust gas, rather than sucking power off the crank, they are the most efficient method of forced induction for an ICE.

Since we're being technically accurate: supercharging is the process of compressing the intake air of an engine in order to increase its volumetric efficiency (output versus displacement). Turbocharging is therefore a type of supercharging. Although they are usually described as different processes by convention, a turbo is just a supercharger that is driven by a turbine rather than a belt drive.

Picture a heat exchanger.

Picture a heat pump.

Picture an evaporative cooler plenum, with atomized tap water fed under pressure from a 20 Liter tank. This is the topical-to-thread part. Now think outside this box. Clear the laboratory of your mind, and let's build a different, and relatively cheap and interesting box in our minds' eyes now:

Picture an array of evacuated-tube "solar" collecters (http://schroderzimmerly.com/CPC_technicalspecifications.html).

Put as many as you can 1)afford and 2) fit, under (yes, under) a BIG but light vehicle.

Give them a plexiglass shield on the bottom of the collector box, with fresnel concentration, and mylar trough reflectors on top.

Add Stirling Engine (http://www.bekkoame.ne.jp/~khirata/academic/schmidt/schmidt.htm), plumbed between water-mist ram-air plenum/condenser and under-chassis infrared heat collector array

Add master motor/generator to Stirling drive, 60kW should do

Add High-Amperage capacitors

Add hub motor/generators from China

And front air-dam vortex-generator(s) swirling close-to-road air up, in, and around hot-side manifolds.

And the wires and inverter/controller, plumbing, refrigerant, sealing wax, and other fancy stuff

PUFF!

OK try again, get out of debt and/or hospital, get it right on 2nd prototype, and then...

Drive all day in HOT ROAD climates. Drive fast in HOT DRY climates: Any desert highway will do. In the Emirates there's hot asphalt and money. They both may start smelling really (really!) good. When excess power rears its lovely head, feed it back into a tesla grid under the highway, and drive at night on the surplus.

Before the submerged highway Tesla-grid, drive for up to an hour on a normal, contemporary dark desert highway, cool wind in your hair (free air-conditioning always)

Warm smell of Colitas, etc.

You'll drive on for a limited time after dark using the thermal mass of the highway- it just gets progressively slower until hopefully you're where you want to be:

Easy Street.

I'm talkin sustained highway speeds just like today, on any hot desert highway. No fuel- just this car, some water, a hot road, and a capacitor/battery/hybrid kick to get it moving and sucking up heat. Evian or other bottled water would still be economical for the evaporative chiller, if that's all there is (but tap or slightly brackish water is OK with a flush-out/injector cleaning now and then).

Build 1,000 of these HRP (Hot-Road-Powered vehicles) per year, and become obscenely rich with a few hundred friends.

Build 10,000 and... you make the gross calculations. It's a very big number, probably exceed €300,000,000.00 in limited-production year 1.

Think about it: Hot asphalt, major infrared emitter. Infrastructure already in place for millions of hot empty miles.

Think some more.

It's patentable- Go get 'em, Tiger.

Then give me alms, because I just thought of this and published it publicly right here. You can PM me for my Bank deposit and contact info.

to hypwader:

It might be informative for you to compute the thermal power radiated by a perfect black body at even boiling water temperatures. (Your hot asphalt will radiate considerable less as it is cooler and power radiated is proportional to the fourth power of the Kelvin temperature.) Then assume the sterling engine is as perfect a converter of thermal energy to mechanical energy as possible. I.e. ME = TE{(Th -Tc)/Th} where Th is the hot temperature, but that will be lower asphalt (even if concentrated IR is used!)* and Tc warmer (higher) than the air temperature. ME and TE are the mechanical power produced and the Thermal power input. For example, on your hot days, Tc =~300K, Th < 400K so (ME/TE) < 1/3. That is you will get less than one third of the thermal input power as the output mechanical power from the Sterling engine. I will not bother to look it up and calculate (but easy to do) how much is the maximum power radiated by each square meter of asphalt at 400K, but realistically it will both be cooler and not a perfect black body. I bet it is less than 3x75 watts, so then the mechanical power is only 75W. Now if memory serves me that is approximately 1/10 of a horse power.

Lot of luck keeping up with traffic in a huge car (Bottom area about 10 square meters) with much less than a 1 HP motor. :D :bawl:
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*Most people think that more concentration means hotter temperature, but that is only because the sun is so hot and burning ants with concentrated sunlight is their only experience with concentrated radiation. It is not hard to show that the temperature produced in a target cannot exceed the temperature of the radiation source. The argument goes like:

Assume source 1 at temperature T1 radiates and its concentrated flux heats target 2 to T2 (where T2> T1). Now let the "back side" of target 2 be the (more intense) source of radiation passing thru an identical concentration system to heat target 3 to T3, where again T3>T2, etc.

Thus, with a chain of these target/sources and concentrators between each of them the original source could be an ice cube and way down the chain, a steel plate, target Tn, is melting under the flux from target T(n-1)!

It is also possible to show that if the target temperature could be greater than the source temperature, then unlimited energy can be produced by the flame of a match. - I.e. you can violate conservation of energy.

Thus, your concentrators are useless. Just let a black plate directly absorb the heat radiation from the asphalt and it be the thermal input to the Sterling engine. I will just mention that to radiate away the waste heat at less than 300K the radiator will be much bigger than the car. – Perhaps if oriented to the wind it can have you sailing along with traffic. :cool:

I bet with a realistic size car you get at most 0.3HP from the Sterling motor.
Do the actual calculation - it is not hard.

Physic is a cruel master, disallowing lots of nice ideas.

To Billy T:

Oh, that. That was a case of drunken inventing- I was a little tipsy when I thought it up. Actually more than half-baked, though. See, you left out at least half the energy equation- think of the evaporatively-cooled heat sink. Consider the Stirling engine's "fuel", too.

I may have been muddle-headed about the evacuated-tube collecter arrays- I'm fascinated by them even when sober. If a dark mass emits proportionally with absorption, and a dark desert highway is up to melt-your-sneakers heat (which it usually is at in the deserts I've visited) there's a thermal differential to be exploited.

I'll try and run some reasonable numbers soon, but I suspect there's enough heat to scoop up and convert- if not through infra-red, then just sucking the air up from the surface through an exchanger.

Or to think about it in a relative way: Consider an internal-combustion engine, and its notorious 20% (being generous) thermal efficiency. Now imaging the total heat coming off a working ICE as waste.

How much comparative heat am I scooping up as I whiz along my desert highway, hmmm? With a big thermal anode (heat-pump and evaporative cooling heat-sink) and an efficiently-beating heart of Stirling?

"Physic is a cruel master, disallowing lots of nice ideas."

Physics is our biyatch. At least I sometimes think so when I've had a few drinks.

... If a dark mass emits proportionally with absorption, and a dark desert highway is up to melt-your-sneakers heat (which it usually is at in the deserts I've visited) there's a thermal differential to be exploited.At any given wavelength the coeficcient of emissivity, e, and absorption, a, are equal* (must be or can again exploit the difference to make energy -violate conservation of energy) but one can have a hot absorber with low e (=a) in the IR range where Black body has most of its radiation (so its radiative losses are low) being heated by a hotter source, like the sun, and at its dominate wavelengths have a (= e) nearly unity. I.e. you can absor well and emit poorly if there is big difference between source and absorber temperatures.

Do you think that a spoon full of water will boil if dropped on your "sneaker melting" hot asphault at its max temperature? (Probably a couple of hour after noon on sunny day.) I doubt it, but it might if only a tiny drop. The heat of evaporation (940Cal /gram if memory serves) is large and will cool the asphault.

I'll try and run some reasonable numbers soon, but I suspect there's enough heat to scoop up and convert- if not through infra-red, then just sucking the air up from the surface through an exchanger.I bet that hot air rising thru turbine is a greater energy source than the IR from the asphault. Would be harder to get good equation for the convective mass flow that the IR, but if you can find one, it would be interesting to know at what temperature a long strip (road) black has equal IR and convective energy outputs. To keep both calculations separate, (not an iterations of two equations for the solution) assume neither cools the road (sun input is keeping constant road temp)

...Consider an internal-combustion engine, and its notorious 20% (being generous) thermal efficiency. Now imaging the total heat coming off a working ICE as waste.
How much comparative heat am I scooping up as I whiz along my desert highway, hmmm? With a big thermal anode (heat-pump and evaporative cooling heat-sink) and an efficiently-beating heart of Stirling?The Carnot equation for ME/TE ratio I gave in last post is the best any thermal converter can do (also "violation of energy conservation" provable if not true) If MEA is the actual and MEC is the Carnot limit Then one could define (I do not know if I am inventing this or it is old) coeficient of performance, CoP for an ICE as CoP = MEA/MEC. Real Stirling engines have this CoP a little less than unity. The ideal Stirling engine is "running the Carnot cycle;" Again: no thermal engine can due better than that.

Yes, evaporating some water would make the waste heat rejection off the "radiator" would make it much smaller.

If you live near a hot level asphault road, it might be fun to try to make a "Hot Air Car Sailor." I.e. a very light weight but large open area square frame with wheels at corners and set of sloping slates (like "ventian blinds") to deflect the rising air towards the car's rear. As there would be some slight horizontal wind and your road not exactly level - I would require it to move either way on the road before accepting that you had made one actually work. (and of course, some evidence you were sober at test time.) :D

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*Most people over generalize this and think a = e, usually on vaguely beoing aware that the values are not constants. I.e.they forget this "a = e" is true at each wavelength, but forget the values can be a very strong function of wavelength.